655 flowtest results are in....

[Directconnection]

Stock 655 G-head #s flowtested by me (and Jim) tonight at my place.

1st off... the short turns on these heads are HORRIBLE, especially on the exhaust. It's a flat floor with (and I kid you not) short 90 degree turn to the seat with a sharp edge. To properly fix this, you'd need a LOT of attention on the short turn because it's just too darn..... short.

The intake: because the floor is lowered a lot, the angle/transition to the short turn is now more abrupt than the 287/445.

Here's the #s in which I was surprised that it flowed as well as it did in this state:

Intake:

.100 57.5
.200 110.1
.300 142.9
.400 151.7
.500 157.8
.550 158.7

Exhaust:

.100 43.6
.200 80.8
.300 102.4
.400 110.1
.500 112.2
.550 112.9

Going off my #s from a stock 445/287.... the 655 seems to outflow it on the intake side down low, but not at the higher lifts . The exhausts..... suffer from all angles, but don't really get "smoked" like I thought it would. Don't get me wrong.... the 445/287 is still a much better design and does flow much better stock to stock, but it's not a 20 cfm difference one would think.

I wanted to work one slightly before Jim had to leave with his head, but it was getting rather late. I am certain I can make it work rather well, but am certain not as good as the 445/287 with the same amount of attention.

***Edit*** Update 11-23-10 Cutaway pictures posted of the 445 vs 655 in post #331

[turbovanman²]

Very interesting, I guess with proper porting, it would fix the higher lift problem.

For a stock cam, seems ok though.

Guess we need the stock G head numbers from the other models to compare, :eyebrows:

[boost geek]

Wonder how the 655 would flow on the intake unported with a 44mm valve. The bowl tapers down just above the valve seat.

[Dave]

Good info to know. :thumb: Thanks for taking the time.

[GLHNSLHT2]

Flow tests compared to a stock 782 as well as other heads have been on TD.com since 12/2006. Same bench same day tests. Nice for you to play catch up. :rolleyes:

http://www.turbododge.com/forums/attachments/engine-general-exhaust-induction/21169d1166287611-stock-782-vs-stock-655-8v-scan0002.jpg

http://www.turbododge.com/forums/attachments/engine-general-exhaust-induction/21170d1166287856-stock-782-vs-stock-655-8v-scan0003.jpg


http://www.turbododge.com/forums/f4/f15/127958-stock-782-vs-stock-655-8v.html

[BadAssPerformance]

Flow tests compared to a stock 782 as well as other heads have been on TD.com since 12/2006. Same bench same day tests. Nice for you to play catch up. :rolleyes:

Thanks for sharing over here, some of us havn't been able to go to TD since 2006... can you post the rest of your findings for thse of us who are unable to log in there?

[Directconnection]

Thanks for sharing over here, some of us havn't been able to go to TD since 2006... can you post the rest of your findings for thse of us who are unable to log in there?

"Nice for you to play catch up. "

Nobody can take what thepoope spurts out for "tech info" since 1996 with a grain of salt, hence why I decided to flow one after all these years.... and my opinion hasn't really changed at all.

[GLHNSLHT2]

Those aren't "what the pope says" They're scans of printouts given to him by Dick Flynn of Flynn Engineering. Kinda hard to dispute that.

[BadAssPerformance]

http://www.turbododge.com/forums/attachments/engine-general-exhaust-induction/21169d1166287611-stock-782-vs-stock-655-8v-scan0002.jpg

Do you have a better resolution copy of this where the numbers are ledgible?

And again, please post the rest of your info for those of use not allowed to log into TD. Thanks...

[RoadWarrior222]

Arrrgh, what's that horrible noise, someone needs to retard snark.

Provenance of particular sets of results aside, it's always great to have more than once source. Hey if everybody's results are all over the map, THAT tells us something too.... that the manufacturing was variable and you can get a power bump by chopping and changing stock heads.

Bring 'em on, more results the merrier I'd say. (BTW did mpgmike post some on that head, off to look)

[GLHNSLHT2]

Do you have a better resolution copy of this where the numbers are ledgible?

And again, please post the rest of your info for those of use not allowed to log into TD. Thanks...

The #'s aren't legible on that scan because it's the 655 #'s posted over the 782 #'s to compare the curves. Dark lines are 655 light are 782. I'll see if I can find a copy of the original 782 scan. But I don't have my own puter right now so it might be a while. Or I'll see if I can get The Pope to chime in here.

[zin]

Those aren't "what the pope says" They're scans of printouts given to him by Dick Flynn of Flynn Engineering. Kinda hard to dispute that.

:lol::lol::lol::lol:

That's the name of my company... I've been called worse.:rolleyes:

Funny that I missed someone in the TM community that has my last name and the same name for their company!

Mike

[zin]

WOW!! I just went to TD to see if I could see the numbers better there... I use FireFox with the "No Script" add-on to block other sites from running scripts that can hi-jack, etc... 13 of them running on that site!! And I'm not including TD itself or Google (everyone is running Google analytics).

I almost feel like I need to take a shower!:lol:

Mike

[Directconnection]

Jay, in all honesty... comparing the 655 to a 782 isn't really beneficial. It's like comparing a Max wedge to a 906 when you should be comparing the two competing likes: the 655 and the 445/287 Like a 452 vs a 906.

And the 445/287 does indeed outflow the 655 in both stock forms all done on the same flowbench. I have the 445/287 #s here, I just didn't have time last night or tonight to post them.

But typically, every stock g-head I have ever flowtested (my bench and others) flow right around 161-164 cfm at .500" lift and around 125-128 on the exhausts.... at .500" Where the 655 does shine is the mid lift intake #s due to it's large intake volume. But at .400 and above, it suffers greatly due to the bad short turn and the airspeed not being able to make the turn.

The intake side can be made to work pretty well even though the angle to the seat kinda sux. But the exhaust.... there's really no material at all to begin with on the short turn to make it work as well as the swirl or 445/287.

The 655 is definately NOT one of these long forgotten and overlooked hidden jewels that some want to take credit for.

For the record: my flowbench was reading about 5cfm high as we also tested a stock swirl that same night and it flowed 151cfm at .500" when it typically is in the mid 140 cfm range (Jim, I looked back through my many old tests and confirmed the "145" cfm quote I was telling you about:D)

Ok.... even though this isn't what the 655 comparo is intended to be (we tested the stock 782 to compare it to a highly ported 782 Jim did that night as well)

Here's a stock swirl same night, back to back:

Intake:

.100 50.4
.200 88.4
.300 117.5
.400 139.4
.500 151.7
.550 152.6

Exhaust:

.100 32.9
.200 76.9
.300 92.6
.400 105.9
.500 110.8
.550 111.5

And here's the 655 once again for easy reference:


Intake:

.100 57.5
.200 110.1
.300 142.9
.400 151.7
.500 157.8
.550 158.7

Exhaust:

.100 43.6
.200 80.8
.300 102.4
.400 110.1
.500 112.2
.550 112.9

You can see, once the airflow picks up on the exhaust after .300" point they are pretty much the same. The midrange lift on the intake is easily better than the 782, and of course.... we all figured that with all the volume it has. But, it's still not at the same level as the 287/445.

[The Pope]

that post is a flat out lie, the 655 is not 5 CFM better. My numbers are not far off from Tyler's numbers either. I tested a 782 with curve cut seats and curve cut valves that had no ridges at all like any good shop does for valve work. The 655 I tested had nasty large sharp casting edges and single cut valves and seats like the 60's. The valves had a 1/16" tall sharp ridge on them and they all had over an 1/8" plus wide seal width. I didn't test the G head vs the 782 and the 655 as Tyler's numbers were so close to mine it was a waste of time. A 655 with good valves and seats and the factory cuts cleaned up like the 782 will really flow well.

What's next for you guy's? Let me guess your going to manufacture flow numbers showing the 1 piece and ported 2 piece flowing the same.

[black86glhs]

that post is a flat out lie, the 655 is not 5 CFM better. My numbers are not far off from Tyler's numbers either. I tested a 782 with curve cut seats and curve cut valves that had no ridges at all like any good shop does for valve work. The 655 I tested had nasty large sharp casting edges and single cut valves and seats like the 60's. The valves had a 1/16" tall sharp ridge on them and they all had over an 1/8" plus wide seal width. I didn't test the G head vs the 782 and the 655 as Tyler's numbers were so close to mine it was a waste of time. A 655 with good valves and seats and the factory cuts cleaned up like the 782 will really flow well.

What's next for you guy's? Let me guess your going to manufacture flow numbers showing the 1 piece and ported 2 piece flowing the same.

Hey...that is a great idea. I'll get started on making up the numbers ASAP!!!:rolleyes:

[RoadWarrior222]

I feel there should be a 93 in there, I've always liked 93.

[Directconnection]

that post is a flat out lie, the 655 is not 5 CFM better.

Pope calling kettle black?

It is not a lie Robbie.... both heads were flowtested within an hour of each other, and verified. I even had someone there with me to make sure, who posts here from time to time, but probably doesn't want to get sucked into a debate/name calling thing.

I am not belittling the 655, but it is FAR from what you seem to think it is.

I gave props to it's midlift flow over the 782 which was no surprise.... but it still falls short to the head that they re-engineered to replace it... the 287/445.

Again.... this head is NOT some hidden undiscovered jewel you seem to be dying to have people to give you credit for. It is better than I expected, but I wouldn't sink $ into one.

[mock_glh]

We need to have a dyno test. The original '81-'82 engines with the 655 made 84 hp while the '83 standard performance engine with 445 head made 94 hp, although it also had higher compression so it's not a true comparison. Some information can be found here:
http://www.allpar.com/mopar/22.html

[Juggy]

screw flow numbers. need real world testing. the best flowing heads are not always the ones that can make the most amount of power, especially when forced induction comes into play

[Directconnection]

screw flow numbers. need real world testing. the best flowing heads are not always the ones that can make the most amount of power, especially when forced induction comes into play

True, flow #s are not the be all end all... but from the work *I* myself have done, I've seen the results from increased flow #s. Now, maybe not as much as the chief honcho here in the head shop.... he's done 1,000s of heads in his 30 years.

But, the 782 does indeed have better combustion characteristics....

[black86glhs]

True, flow #s are the be all end all... but from the work *I* myself have done, I've seen the results from increased flow #s. Now, maybe not as much as the cheif honcho her ein the ehad shop.... he's done 1,000s of heads in his 30 years.

But, the 782 does indeed have better combustion characteristics....

Who cares about combustion characteristics....we want numbers. <------J/K:D

[RoadWarrior222]

Combustion characteristics can be.... an interesting factor...

I threw every trick I knew or had heard about at an N/A motor for preventing detonation, and shaved the head aggressively... it worked too well... damn thing runs best when it's 100F out... or on winter gas when we get an early warm spell... I'm working on gaining full control of fuel and spark, either needs to run lean or advance about 5*... or maybe I should just throw a turbo at it :D

[Directconnection]

True, flow #s are the be all end all...

Crap, I typoed again. I meant to say "flow #s aren't the be all end all..."

[Juggy]

True, flow #s are the be all end all... but from the work *I* myself have done, I've seen the results from increased flow #s. Now, maybe not as much as the cheif honcho her ein the ehad shop.... he's done 1,000s of heads in his 30 years.

But, the 782 does indeed have better combustion characteristics....

yeah I was thinking trying to make a bathtub more like the swirl chamber, but im thinking it will def need to be welded at any attempt

[Directconnection]

yeah I was thinking trying to make a bathtub more like the swirl chamber, but im thinking it will def need to be welded at any attempt

There is one person who did just that.... and they are/were on this forum. 240cfm at like .430 or .450 lift? (a *REAL* 240cfm.... not some induced #s) It's crazy, and much like Warren's head: something they vowed to never replicate again.

[Shadow]

There is one person who did just that.... and they are/were on this forum. 240cfm at like .430 or .450 lift? (a *REAL* 240cfm.... not some induced #s) It's crazy, and much like Warren's head: something they vowed to never replicate again.

First off, why would you never replicate something like that again IF you nailed it to begin with? 2ndly, where is the 500+WHP stock cammed mtr that this head is running on? :confused2:

[turbovanman²]

First off, why would you never replicate something like that again IF you nailed it to begin with? 2ndly, where is the 500+WHP stock cammed mtr that this head is running on? :confused2:

Maybe too much work?

You know the guy?

[Directconnection]

First off, why would you never replicate something like that again IF you nailed it to begin with? 2ndly, where is the 500+WHP stock cammed mtr that this head is running on? :confused2:

Who said 500whp? It was 400+whp and an auto ;) I forget which cam....


As for why not do it again? Just ask Warren! Apparently (and not poking fun at you in no way whatsoever) you might not have really spent a crazy amount of time porting a cylinder head. I've only done a 50% job compared to warren, and to tell you the truth.... porting heads is sickening. I've lost the love for it once I made it my side business.

The head I am talking about had lots of material added/welded to the roof as the port ran through into the top of the head. I have pix of one of his later g-heads he did on my old computer, and it is a quality job.

Just so you know I am not BSing you.... Marra, Menegon, and Donovan all swear by him as they've seen/experienced his work. He just lays low.... real low as it is understandable that there are nay-sayers.

[glhs875]

Who said 500whp? It was 400+whp and an auto ;) I forget which cam....


As for why not do it again? Just ask Warren! Apparently (and not poking fun at you in no way whatsoever) you might not have really spent a crazy amount of time porting a cylinder head. I've only done a 50% job compared to warren, and to tell you the truth.... porting heads is sickening. I've lost the love for it once I made it my side business.

The head I am talking about had lots of material added/welded to the roof as the port ran through into the top of the head. I have pix of one of his later g-heads he did on my old computer, and it is a quality job.

Just so you know I am not BSing you.... Marra, Menegon, and Donovan all swear by him as they've seen/experienced his work. He just lays low.... real low as it is understandable that there are nay-sayers.




Why keep this so secret? I have ALOT of time/money invested in my 8V head. And it runs very well!! Will I do another one and maybe try to improve upon what I have now? Most likely not! Because even after all the countless hours of porting and uprgraded valvetrain parts done to the 8V, a stock 16V head will make more power and needs very little else to turn the R's! Send a 16V Neon head to Indy cylinder heads and have it cnc ported for a very reasonable price and you will have 300+ cfm!!!



I have my experimental/learning 8V head freshened up. I doubt I will even use it!! I've run into too many brick walls with it trying to get what I want out of it. From what I have learned from this head is that I need to start completely over if I want to stay 8V!

[cordes]

From what little I've read of folks with claims such as what Steve mentions I would keep quiet about it too. Too many guys know it all and the nay sayers will come out of the woodwork. I can think of three examples off the top of my head and they weren't nearly as outlandish as the work in question. Note that I'm not saying Steve's claims are untrue at all, but that it would be viewed as an outlandish claim by most all.

[Warren Stramer]

There is one person who did just that.... and they are/were on this forum. 240cfm at like .430 or .450 lift? (a *REAL* 240cfm.... not some induced #s) It's crazy, and much like Warren's head: something they vowed to never replicate again.

I would do another head IF the bulk of the material was removed by CNC. I already have some new ideas I would like to try but no way would I do another by hand unless someone paid me alot of money.
The only way I would go thru all the work to convert to 16V is if I also went rear wheel drive.
So for now I'm going to see how far this old 8V will take me. I must admit I have a new enthusiasm for these cars, so I'm just going to keep running it as a sort of outlaw super stocker.

[turbovanman²]

I would do another head IF the bulk of the material was removed by CNC. .

Why couldn't you get that done? If you know or can find a decent machinist with the right machine, they could replicate it? right?

[Directconnection]

Why couldn't you get that done? If you know or can find a decent machinist with the right machine, they could replicate it? right?

It's very expensive. The digitizer is crazy expensive, and the amount of code is mindboggling.

3 axis is simple.... but 5 axis is whole other world. A simple move in 5-axis 3D machining could be 100's of lines of code, where as in 3 axis.... just 2-4. It's not something just any machine shop with a cnc can do.... but technology is making things easier for the smaller shops. My friend's shop has a few 4 axis cncs and does some great 3d work. He made these sectional curved banister railings for this bazillionaire in MA that cost over a million dollars when all said and done... and he's doing another for him soon. Must be nice to spend a million dollars on a custom railing for your house. He also does custom cnc work for custom rifle stocks.

Anwho... off tangent...

[Shadow]

Who said 500whp? It was 400+whp and an auto ;) I forget which cam....


As for why not do it again? Just ask Warren! Apparently (and not poking fun at you in no way whatsoever) you might not have really spent a crazy amount of time porting a cylinder head. I've only done a 50% job compared to warren, and to tell you the truth.... porting heads is sickening. I've lost the love for it once I made it my side business.

The head I am talking about had lots of material added/welded to the roof as the port ran through into the top of the head. I have pix of one of his later g-heads he did on my old computer, and it is a quality job.

Just so you know I am not BSing you.... Marra, Menegon, and Donovan all swear by him as they've seen/experienced his work. He just lays low.... real low as it is understandable that there are nay-sayers.

Your correct, I've never spent a lot of time on one of these heads, just enough time to open it up to what I thought would flow well for what I was intending to do. Don't get me wrong, it's still time, but nothing that would wreck me, yet I do get what your saying.

I thought you were implying that it was a Big secret, and that's why it would never happen again! lol

I said 500+WHP because I couldn't imagine running a head of that potential and Not using it Close to it's potential! :confused:

[RoadWarrior222]

You guys do know you can get cutting lube and you don't HAVE to use blood right? .... just checking ;)

[Directconnection]

You guys do know you can get cutting lube and you don't HAVE to use blood right? .... just checking ;)

Naw, as you cry... the tears running down your face keep the single cut burr free of buildup:D

[Shadow]

Actually, the #1 reason we have never had to get that involed is prob because we decided to stick with +1mm valves on all the heads we've done.

I knew that any valve (specialy Intake) bigger than that would literally double the work! Same goes for the base heads we start with, all G-heads, again, literally 1/2 the work of doing a proper 782!

[glhs875]

To me the purpose making the ports bigger and flowing more is to allow the power to be shifted higher in the R's,which makes ALOT more HP. But then on an 8V you have the lack of easily available cams/valvetrain parts that will work well in the higher R's ( I'm talking 7500rpm+) Big valves are heavy and require ALOT of spring pressure which in turn puts more stress on the lash adjusters/rocker arms etc. It's a snowball effect and will happen much sooner on an 8V than on a 16V.

[bakes]

Did you raise the exhaust ports or just intake port ?

[RoadWarrior222]

Big valves are heavy and require ALOT of spring pressure which in turn puts more stress on the lash adjusters/rocker arms etc. It's a snowball effect and will happen much sooner on an 8V than on a 16V.

And you can make it worse without attention to the shape of the valves... if you've done all the development to the chambers and seats and bowls and that and actual valve area is where all your flow is, your spring is likely trying to pull in a parachute against a hurricane.

[Shadow]

Did you raise the exhaust ports or just intake port ?

Who are you asking?

[turbovanman²]

Who are you asking?

glhs875?

[rib256]

to anyone, how would you fix the "horrible" exhaust turns? Add material and cut a new path?

Also, what do you use to fill said space?

[turbovanman²]

to anyone, how would you fix the "horrible" exhaust turns? Add material and cut a new path?

Yes, you want the port as straight as possible, think modern Japanese motorbike, :nod:

[Shadow]

I've never even concidered "filling" anything on one of these heads. Raise the roof appropriatly and open up the cross-section.

[Directconnection]

to anyone, how would you fix the "horrible" exhaust turns? Add material and cut a new path?

Also, what do you use to fill said space?

Yes, but if you do that, then you now have a 445/287 casting with epoxy that can fall off.

[turbovanman²]

Doesn't Steve use epoxy?

[boost geek]

My head is a 445 with intake ports larger than a 655. I still wanna do a raised intake port version.

[zin]

to anyone, how would you fix the "horrible" exhaust turns? Add material and cut a new path?

Also, what do you use to fill said space?

On the exhaust side, you pretty much HAVE to have it welded up, I wouldn't trust my turbo to any epoxy...

Mike

[Directconnection]

Doesn't Steve use epoxy?

Yes, and I know of a few people that had the epoxy come off....

[RoadWarrior222]

Is this people thinking JB Weld is invincible, or the super duty harder to find, 2000F epoxies???

[Directconnection]

Is this people thinking JB Weld is invincible, or the super duty harder to find, 2000F epoxies???

The person I know (very reputable here...) had the right kind of epoxy and it lasted but a few years....

[OmniLuvr]

bakes, i believe that someone (hopefully me soon) built up welding beads ABOVE the intake ports, in the valve cover area, so that the intake port roof can be raised more.

and juggy, why do you want a swirl style combustion chamber?

[turbovanman²]

bakes, i believe that someone (hopefully me soon) built up welding beads ABOVE the intake ports, in the valve cover area, so that the intake port roof can be raised more.

and juggy, why do you want a swirl style combustion chamber?

SMP welded up an 8 valve head, HUGE ports, he also tested swirl vs g head and made more power on a swirl, the combustion chamber is far superior to a g-head.

[Directconnection]

Stephane actually made a plate that bolted to the intake side of the head

[turbovanman²]

Stephane actually made a plate that bolted to the intake side of the head

And he raised the ports, you could see the welding on top of the head.

I had the pics saved but the hard drive failed, :(

[bakes]

I have seen 3 heads done /welded with intake ports raised but never yet one with a raised exhaust port this is why i ask.

[4 l-bodies]

I have seen 3 heads done /welded with intake ports raised but never yet one with a raised exhaust port this is why i ask.
Your gonna need someone with a pretty small stinger to weld up that exhaust port. WJ is about 1/2" downstream of the guide. Raise the roof enough and you will find it!:p I'd be curious how it would hold up on a street driven vehicle without that WJ being functional.
Todd

[RoadWarrior222]

The person I know (very reputable here...) had the right kind of epoxy and it lasted but a few years....

A few years is actually longer than I would have expected on a turbo car. I thought it might be an option on a race motor redone every winter.

[zin]

Your gonna need someone with a pretty small stinger to weld up that exhaust port. WJ is about 1/2" downstream of the guide. Raise the roof enough and you will find it!:p I'd be curious how it would hold up on a street driven vehicle without that WJ being functional.
Todd

I don't know... I would think it fairly important, being on the exhaust side, but I'm sure we could come up with a way to keep coolant flowing if need be... Say weld in a piece of AL tubing in a horseshoe shape to give the heat a place to go, essentially re-locating the WJ...

I'd also love to see the welding that has been done before, just so I don't re-invent the wheel or repeat bad history...

Mike

[bakes]

What i had in mine was to cut 4 openings on roof of the valve train area and back fill the top of the exhaust port roof then regraft the tops back rasied of course on and back fill the roof of the intake.

[Directconnection]

I'm getting lost in the direction of this thread (doesn't bother me... so keep shootin' away:D) But are we talking about the 655 or 445287 g-head? No sense trying to add weld and fix what's wrong with the 655's floor and short turn, when essentially the factory did just that. I'd say start with the 445/287 and do as you guys are thinking with the roof.

Wouldn't it be nice to R&D the G or swirl and have an out of the box as-cast 240+cfm head? Then leave room for additional portwork and have a 260-270 cfm 8v would be awesome.... and possible. Only if my pockets were deep enough and I rubbed elbows with Esslinger. They were *partly* interested in what I had to say a few years ago.... Who has the fundage to help us? Hey Alan!!!!! Oh.... he never reads any of the 8v threads/posts....:D

[zin]

Wouldn't it be nice to R&D the G or swirl and have an out of the box as-cast 240+cfm head? Then leave room for additional portwork and have a 260-270 cfm 8v would be awesome.... and possible. Only if my pockets were deep enough and I rubbed elbows with Esslinger. They were *partly* interested in what I had to say a few years ago.... Who has the fundage to help us? Hey Alan!!!!! Oh.... he never reads any of the 8v threads/posts....:D

Well... I'm planning on going to a 3-D printing (rapid prototyping) seminar this coming Thursday... maybe I can con one of those guys into doing something... Too bad it would only be good for testing (AFAIK), I don't think a sintered metal cylinder head would hold up to much!

Mike

[RoadWarrior222]

With swirl and other "economy" or emissions type heads, I think where the typical porter goes wrong is assuming all that is wrong and bad and robs power... well it's not a high power design philosophy behind it of course, but fighting against it doesn't really get you much. Better I think to enhance the design of the head, work with it, make it swirl stronger and harder if that's the way the air is going in... 'coz doing it the other way, you probably kill all the stock flow and start from zero trying to push it the other way.

This is generally speaking, from observations of other motor porting discussions.

[puppet]

I'd think raising the exhaust port/bowl area would stall flow .. considering you have to turn down again to the manifold. ... intake side I can see.

RW .. for sure there's ton's of work porting heads ... not just grinding. Ideal situation is to have a flow bench close at hand to gauge progress .. but, there are things like pressure recovery that wouldn't show up on the typical flow bench. Been reading a discussion about this on another forum ... it has to do with how well the air flows past the valve into the chamber. Flow shouldn't stall here or go turbulent but rush past the valve like a venturi.
Because of the velocities involved it's not something that is apparent on a regular flow bench .. but can kill performance if it's not right. One fella tested a head with really big valves and stockish port runners. Attention was paid to the deshrouding shape instead so flow transition was real good. Surprise to the guy testing was the engine performed very well considering the lack of port work to match the sized valves used.

It goes to show that every step of the intake charges journey can be effected by some totally obscure place in the port, bowl or chamber. Even things you can't check.

[turbovanman²]

Your gonna need someone with a pretty small stinger

Say WHAT? :wow1:

[BadFastGTC]

Steve,

Were these one's I did? I hadn't heard of this happening to anyone except for mine! For the record, I use a product called Splash Zone. Impervious to fuel, oil, and it's waterproof. You cannot use it in exhaust!



Yes, and I know of a few people that had the epoxy come off....

[Directconnection]

Steve,

Were these one's I did? I hadn't heard of this happening to anyone except for mine! For the record, I use a product called Splash Zone. Impervious to fuel, oil, and it's waterproof. You cannot use it in exhaust!

Yes, it was you... but I didn't want to speak on your behalf, ya know?

I'm pretty sure we've had similar things here at the shop years ago, too...

[Ondonti]

Funny that people are tripping out at 240 cfms at peak lift as if its some big deal. Only a few here are worried about how the head performs. Flow is easy. Building a good head is not.

I am sure Warren has moldings sitting around.

[RoadWarrior222]

RW .. for sure there's ton's of work porting heads ... not just grinding. Ideal situation is to have a flow bench close at hand to gauge progress .. but, there are things like pressure recovery that wouldn't show up on the typical flow bench. Been reading a discussion about this on another forum ... it has to do with how well the air flows past the valve into the chamber. Flow shouldn't stall here or go turbulent but rush past the valve like a venturi.
Because of the velocities involved it's not something that is apparent on a regular flow bench .. but can kill performance if it's not right. One fella tested a head with really big valves and stockish port runners. Attention was paid to the deshrouding shape instead so flow transition was real good. Surprise to the guy testing was the engine performed very well considering the lack of port work to match the sized valves used.

It goes to show that every step of the intake charges journey can be effected by some totally obscure place in the port, bowl or chamber. Even things you can't check.

I was working without a flow bench, but using jets of water to show me how the surface affected flow at various points. Also used bulk water flow to see how it emerged from port/valve. Used a valve trick contrary to the "ditch cut" theory, which was developed on closed/constricted head motors in the UK, which is used on the back of intake, front of exhaust to tumble flow over the edge, rather than preventing it reverting. Result is that it streamlines flow around the valve to approx egg shape, tighter to the valve, rather than a splayed cone, which is eventually egg shape about 10 valve diameters downstream (When there's not gonna be that much room.)

[Warren Stramer]

Funny that people are tripping out at 240 cfms at peak lift as if its some big deal. Only a few here are worried about how the head performs. Flow is easy. Building a good head is not.

I am sure Warren has moldings sitting around.

Copy these-go fast.

[BadAssPerformance]

:clap:

[turbovanman²]

Copy these-go fast.

Warren, your a man far ahead of the times, :hail:

[glhs875]

Personally,I think there is too much stress being put on the lowered port floor of a 655 head being such a terrible thing! Look at some REALLY good flowing small block Chevy heads for instance. The port entrance of the head is low enough that the floor of the port actually rises above what the entrance is before the short turn radius area so it can make a more gentle turn. Some of these heads flow REALLY WELL!

[RoadWarrior222]

Heh, I thought that was the point being made, that you couldn't remove more material to get a wide turn into the valve, you'd have to add to do it.... in which case you have to hog out the roof to keep the CSA.

[puppet]

Personally,I think there is too much stress being put on the lowered port floor of a 655 head being such a terrible thing! Look at some REALLY good flowing small block Chevy heads for instance. The port entrance of the head is low enough that the floor of the port actually rises above what the entrance is before the short turn radius area so it can make a more gentle turn. Some of these heads flow REALLY WELL!Flow great but don't perform in the 1/4 or in upper rpms. It's no mystery that a bigger hole will flow more air ... but what does that really mean on a running engine? Who's run one of these heads that can give some input as to how well they work in practice vs one of the other "modern" castings?

[The Pope]

Personally,I think there is too much stress being put on the lowered port floor of a 655 head being such a terrible thing! Look at some REALLY good flowing small block Chevy heads for instance. The port entrance of the head is low enough that the floor of the port actually rises above what the entrance is before the short turn radius area so it can make a more gentle turn. Some of these heads flow REALLY WELL!

The port floor on the 655 I actually lower it. It has a big hump right before the guide and I take 3/32" off it to straighten it out to the gasket. The 782 has what looks like a negative inside turn, yet I know they can be made to flow great without adding material there. Port floor height at the gasket is meaningless other than a bigger port with more volume. This raised floor business you here about is always at the valve sea where the 655 has plenty of inside turn. The thing that sucks is that Mopar put an emissions wave to the floor, not jagged peaks that people here have posted. Emission bumps were a big deal in the 70s to atomize fuel, lame.

[The Pope]

Flow great but don't perform in the 1/4 or in upper rpms. It's no mystery that a bigger hole will flow more air ... but what does that really mean on a running engine? Who's run one of these heads that can give some input as to how well they work in practice vs one of the other "modern" castings?

Terry with the 11 second van is running one and one of my plenums, may have to look the posts up here but I believe he has the first van to run 12s with less than 30 PSI and he ran a mid 12 at 25 PSI before any real tuning. He posted he thinks he'll run 11s without 30 PSI now. Granted it's been a while who knows how fast he's going, he has been posting for +40 injectors on the local list to he is tuning I believe at this time.

[Directconnection]

Terry with the 11 second van is running one and one of my plenums, may have to look the posts up here but I believe he has the first van to run 12s with less than 30 PSI and he ran a mid 12 at 25 PSI before any real tuning. He posted he thinks he'll run 11s without 30 PSI now. Granted it's been a while who knows how fast he's going, he has been posting for +40 injectors on the local list to he is tuning I believe at this time.

He's done LOTS to the van besides the 655 head. I'm sure he's gotten his to work decently... but all in all, the 655 is azz. There is NO short turn... it's a friggin' 90 degree with no radius... a sharp edge. Have fun working that out...

[Directconnection]

This raised floor business you here about is always at the valve sea where the 655 has plenty of inside turn. The thing that sucks is that Mopar put an emissions wave to the floor, not jagged peaks that people here have posted. Emission bumps were a big deal in the 70s to atomize fuel, lame.


Emissions Bump? What planet are you from again? :confused:

[Juggy]

He's done LOTS to the van besides the 655 head. I'm sure he's gotten his to work decently... but all in all, the 655 is azz. There is NO short turn... it's a friggin' 90 degree with no radius... a sharp edge. Have fun working that out...


http://www.turbo-mopar.com/forums/showpost.php?p=395495&postcount=100

idk....looks like its going to work out pretty nice judging from these pics. and im sure boost will help aid airflow through that 90 degreed sharp edge turn, which terry did a nice job of smoothing out

[turbovanman²]

Terry with the 11 second van is running one and one of my plenums, may have to look the posts up here but I believe he has the first van to run 12s with less than 30 PSI and he ran a mid 12 at 25 PSI before any real tuning. He posted he thinks he'll run 11s without 30 PSI now. Granted it's been a while who knows how fast he's going, he has been posting for +40 injectors on the local list to he is tuning I believe at this time.

He tunes alot, and he had alot of work into his old setup, he has barely run the new setup so you can't compare yet, plus he's changed the turbo this time out too.

[zin]

Look at some REALLY good flowing small block Chevy heads for instance. The port entrance of the head is low enough that the floor of the port actually rises above what the entrance is before the short turn radius area so it can make a more gentle turn.

Looks can be deceiving, if you look at the early 2.8L 60*Chevy (iron heads), they have a "bump"/mole hill just before the short side... it takes up 15% of the port! BUT, makes the port flow 15% MORE than without it! Air flow can be a tricky thing, and even then raw flow numbers don't equate to higher HP.

We tend to ignore what happens to the air after it gets past the valve, but it is just as, if not more important than the raw flow... Just food for thought.

Mike

[RoadWarrior222]

If you're trying to get air to go round a sharp corner, you can always "trip it over" so to speak.

[glhs875]

Looks can be deceiving, if you look at the early 2.8L 60*Chevy (iron heads), they have a "bump"/mole hill just before the short side... it takes up 15% of the port! BUT, makes the port flow 15% MORE than without it! Air flow can be a tricky thing, and even then raw flow numbers don't equate to higher HP.

We tend to ignore what happens to the air after it gets past the valve, but it is just as, if not more important than the raw flow... Just food for thought.

Mike



That's a good example of what I was talking about.

[The Pope]

He's done LOTS to the van besides the 655 head. I'm sure he's gotten his to work decently... but all in all, the 655 is azz. There is NO short turn... it's a friggin' 90 degree with no radius... a sharp edge. Have fun working that out...

What are you talking about? I have 2 655's and there is no big sharp 90 degree edge on the intake short turn? Even my big valve 655 opened up to the seat didn't leave a 90 degree edge for a short turn.

[The Pope]

http://www.turbo-mopar.com/forums/showpost.php?p=395495&postcount=100

idk....looks like its going to work out pretty nice judging from these pics. and im sure boost will help aid airflow through that 90 degreed sharp edge turn, which terry did a nice job of smoothing out

http://i146.photobucket.com/albums/r251/gasketmaster/DSCN3980.jpg

um, that inside corner here is the same shape they have before you start cutting. He actually lowered the floor a bunch at the short turn making it small as I have. Eh, I have a brand new 655 still in the Mopar box I guess I need to take some pictures of...

[The Pope]

He tunes alot, and he had alot of work into his old setup, he has barely run the new setup so you can't compare yet, plus he's changed the turbo this time out too.

The point was made, the setup is very impressive far from being worked out compared to what he had before.

[puppet]

What are you talking about? I have 2 655's and there is no big sharp 90 degree edge on the intake short turn? Even my big valve 655 opened up to the seat didn't leave a 90 degree edge for a short turn.
Hold on Rob ... you know full well that the SSR on the 655 is much shallower than on a 445/287. I'm probably wrong here as usual but I see fuel getting stripped out of the flow as the air misses the turn. Same problem the SBC 23* heads have. They flow great but it's just air. Add in the fuel at higher velocity and you'd better have the right curves to make it all work right.

Most likely why Mopar raised these floors once they went to MPFI. Carb's might have masked this issue a little bit. Injectors? ... not so sure the 655 can hang.

[Shadow]

First off, WTF did you guys do to Warrens thread?!# :confused2:

If you want to start a debate about the pros and cons of the 655 maybe you start a new thread?

Having said that, I'll put in my .02$ :eyebrows:

The only benifit I see to the 655 is that an inexperienced porter could do a light "clean-up" and mani port match, and have a pretty decent flowing head compared to the other offerings out there, specially vs a 782!

Let's face it, unless your getting close to maxing out one of these heads, which no one has come close to yet (although Warren is deff looking good for this) having a large cross section, volume flowing chamber, with some psi behind it is going to work decent.

So, is the 655 a large piece of poo, or is it the hidden treasure that some make it out to be? I guess it's both.

Treasure to someone looking to get a decent flowing head on the cheap. POO to someone who wants a Really good flowing/performing head that they can take to the very limits of what one of these mtrs is capable of. :nod:

[puppet]

First off, WTF did you guys do to Warrens thread?!# :confused2:

If you want to start a debate about the pros and cons of the 655 maybe you start a new thread?:focus:


Having said that, I'll put in my .02$ :eyebrows: ... LOL

[Directconnection]

Hold on Rob ... you know full well that the SSR on the 655 is much shallower than on a 445/287.

Your post along with the rest that followed was right on. Some TurboDodge meatsticks try SO hard to be recognized at being on the same level with a Warren, or Mengegan.... that they'll stop at nothing to spurt out illogical information.

Shadow is right: let's not Poope all over Warren's thread anymore and take it over to my 655 flowtest results thread.

Warren's done a kick-azz job..... and I can't wait to see how it does the next time down the strip.

FWIW: I'm hoping to hear about Terry breaking a new personal best next time out too... 655 or not... it's a TM thang :nod:

[The Pope]

First off, WTF did you guys do to Warrens thread?!# :confused2:

If you want to start a debate about the pros and cons of the 655 maybe you start a new thread?

Having said that, I'll put in my .02$ :eyebrows:

The only benifit I see to the 655 is that an inexperienced porter could do a light "clean-up" and mani port match, and have a pretty decent flowing head compared to the other offerings out there, specially vs a 782!


I posted originally on his question even with video. 10 minutes on google instead of asking people here gets answers.

Yes the 655 is super easy to port and build to race with. The BIG BIG down side to the 655 isn't the head and all the direct lie's shoveled on this forum about the head. The problem is the cost of making an intake manifold to feed this head. A real nice ported 2 piece will feed a G head and a 782. You must have a fully welded and properly cut lower piece to match the 655. Then a custom plenum to shorten the runners is also a must. Otherwise the 655 is a complete waste of time. Most don't have the skills or won't spend the money.

All the debate on SSR is BS, it is twice as high as the 782 and only slightly lower than the G head. Stick your caliper in the bowl and measure, not tough. The head has more than enough SSR, more than many V8 heads I've ported. A little blending takes the wave out so it works right. Posting lie's about how the head flows on this forum for no other reason than because I like the head or because I have flow benched it is sad. People looking to actually do something with the 8v engine can make great use of a 655. Steering them away from it with lie's just because you don't like me is a terrible problem with this forum. Soon too many will be using the 655 for lie's like Steve's to matter. Just like bad mouthing Conical springs and the use of PT's over stock lifters. Too many people just know better now.

[Shadow]

All the debate on SSR is BS, it is twice as high as the 782 and only slightly lower than the G head. Stick your caliper in the bowl and measure, not tough. The head has more than enough SSR, more than many V8 heads I've ported. A little blending takes the wave out so it works right. Posting lie's about how the head flows on this forum for no other reason than because I like the head or because I have flow benched it is sad. People looking to actually do something with the 8v engine can make great use of a 655. Steering them away from it with lie's just because you don't like me is a terrible problem with this forum. Soon too many will be using the 655 for lie's like Steve's to matter. Just like bad mouthing Conical springs and the use of PT's over stock lifters. Too many people just know better now.

First off, who you callin a lier? :fencing: I didn't lie AT ALL in my description of the 655 AND I didn't say anything that would steer ppl away from it!

If you read my post correctly, you'd see that I AGREED that for 90+ % of the builds out there it will work fine.

Secondly, I could care less wether it's you or anyone else posting. If I don't think it's right, I'm generally going to say something so that ppl don't get caught HOOK, LINE AND SINKER into believing something that just isn't true.

Lastly, and I mean, FOR THE LAST TIME! (cause how many times do I have to say this) I've never said anything about NOT running PT lifters/Conicles.

What I've said is THERE'S NOTHING WRONG WITH THE FACTORY STYLE SET-UP *IF* you know what your doing!

ALL the :blah: :blah::blah:that you guys put into pushing the PT/conicles and my Charger does EVERYTHING you describe WITHOUT THEM! Can you explain that?

Rob, I'm not dissagreeing that these are all good choises and options for someone to concider when building one of these cars, but that's all they are!

Like everything else, they have their limitations, and frankly I haven't seen where they "FIT" in the "where I'm going with my build" scheme of things.

You say they're a MUST HAVE PIECE, yet here I am, laying down as much or more power than anyone before me with one of these 8v's (Warren being the most recent exception :D) without ANY of the so called problems that you say I SHOULD be having!

The Charger revs as high, clean and smooth and even with the F4 cam, get's better mileage than anything I've heard on these forums. And the ultimate proof is the power I'm making and the longevity of my mtr....no?

So, simply put, if these things were 1/2 of what you make them out to be, why aren't ppl leaving me, and others, that haven't used them in the dust? :confused2:

[Directconnection]

The BIG BIG down side to the 655 isn't the head and all the direct lie's shoveled on this forum about the head. Posting lie's about how the head flows on this forum for no other reason than because I like the head or because I have flow benched it is sad. Soon too many will be using the 655 for lie's like Steve's to matter.

Rob.... I do feel that you aren't really a bad guy at all. You really do take a lot of shat from a lot of people, and end up running away with your tail between your legs every time instead of turning into a crazed madman like many others would.

But you have a serious problem with the Pathological Lying thing.... and you always have in the past.

One thing about me: I never, ever lie.... and I have an uber *crazy* intolerance for ones that do (may be why we butt heads)

You do have a hunger for learning and helping people.... but probably to a fault that you try so hard for a Turbo-God like acceptance, to the point that you don't really have a full grasp of what you're talking about, instead of learning from those that do (ie: the Reeves, Strammers, Menegan, TurboJerry, etc..)

I am not self proclaiming myself turbo god status, but believe me when I tell you that the head flowed those #s exactly that night after flowing a few others before it. If anything, my bench was 5-6cfm *high* that night as Menegan told me after seeing the results posted here, that he found the same thing, yet mid 140s for the swirl, not 150s that I got.

Rob, 5 years ago.... I had 2 job opportunities come before me at the same time. One was the shop I currently work at that is highly regarded in my state, and even surrounding states, as being the best at what they do (75% race engines) The other position I turned down was at an actual machine shop running CNC Fadals, etc... for $1 more an hour AND health insurance vs the *nothing* I have where I am currently at. Not to mention: 10 minute ride across town vs the 40 minutes each way I travel through the boonies, now. Why did I choose less pay, more travel, no insurance, no toling support either over the other shop? Because I had the hunger like you, but was sooooo tired of learning from 2nd, 3rd and 4th hand experience from magazines, books, and sadly.... SDML/TD/TM. Nothing beats 1st hand experience, period. Same thing for my flowbench: I had the option of going with a Menegan head, or bottle the passion up and buy my own flowbench and figure it out on my own. I feel I succeeded... but also would be the 1st to tell you to buy a head from Steve or Todd vs me ;)

1st hand experience buddy :nod: I'm not suggesting you make a career move as you probably make decent $, but see if you can volunteer in a shop part time. You won't believe the mindset you'll have after being in there for a year or two.

Our shop (Butler & Macmaster) currently employs a former Ray Barton, Patterson, and Bill Jenkins employee. (they got sick of living down south and moved back north where their family was still at) A former long time employee that used to work for us, is now the head honcho at Hendricks in the engine R&D program. Scott Maxim. I've met him a couple times when the Hendricks cars were racing up at NHIS. (I'll send you a link) Our shop also used to own a Busch South NASCAR team and then a Crasftsman truck team in the end. (Andy Santare and the Team EJP car) We used to do all the engine work for Ricky Craven before he made it to the big show... the list goes on. Reason for this isn't showing off on my part, it's just that getting your hands dirty in this is rewarding vs. reading about it.... 1st hand experience.

edit: here's Scott Maxim's profile/interview on Hendrick's website: http://www.hendrickmotorsports.com/news_detail.asp?id=2468

[Shadow]

Here's a Q. Who has cross sectioned a 655 head? Anyone? If so, how about posting up some pics for comparison to a regular G and even a 782 head.

All I've had to go on is the MP pic of the G-head with material removed = the 655.

[BadAssPerformance]

655 discussion in the "head copying" thread moved here

[Warren Stramer]

Here's a Q. Who has cross sectioned a 655 head? Anyone? If so, how about posting up some pics for comparison to a regular G and even a 782 head.

All I've had to go on is the MP pic of the G-head with material removed = the 655.

I would very much like to see that.

[puppet]

When I had one of these, the cca came out to around 1.90 .. give or take. The port entrance is as large as the gaskets provided by mopar FWIW.

[Juggy]

how do you measure the CCA????

1.9" is nice for a 2.2L that wants to rev out to 7500 rpm
it would be nice to get it closer to 2.1"

[Directconnection]

Here's a Q. Who has cross sectioned a 655 head? Anyone? If so, how about posting up some pics for comparison to a regular G and even a 782 head.

All I've had to go on is the MP pic of the G-head with material removed = the 655.

Do you mean a cut and sectioned 655? I have cut and sectioned a 287/445 g-head into several pieces on a few different planes.

I would assume Rob has a 655 cut up already....

[John B]

how do you measure the CCA????



What is CCA?:confused2:

[Directconnection]

I think he meant CSA? (Cross Sectional Area)

[Juggy]

What is CCA?:confused2:


I think he meant CSA? (Cross Sectional Area)

hehe oops....what he said!!! we arent talking about batteries here lol....

[Shadow]

Do you mean a cut and sectioned 655? I have cut and sectioned a 287/445 g-head into several pieces on a few different planes.

I would assume Rob has a 655 cut up already....

I mean a 655 that has been cut to show the cross section of the intake, and more importantly, the exhaust ports. Cut right down the center so you can see the entire shape, floor, roof ect. (I don't know how else to describe it, though cross section was the appropriate term?)

[boost geek]

Someone would have to donate an unported head. I only have 1, so not me...;)

[Juggy]

I have a 655 I can take some pictures of. altho its dirty and needs cleaning so I would have to run a sanding bit through the ports to clean up all the carbon.

I plan to port this head out....well more of a cleaning. I dont think there is too much meat to work with these heads other then the valve guide area/back wall in the bowl

[Juggy]

i remember seeing this on another thread posted by Todd (4 L bodies)
thought id ad it to the thread


http://www.turbo-mopar.com/forums/attachment.php?attachmentid=15886&d=1247153009

[Shadow]

That is the pic I was talking about, but I was also told that it might not be 100% accurate. If it is, the exhaust port is in BIG trouble!

Rob, this is no time to turtle! Grab all the info and pics you have of the 655 and accept your invite to the party and let's take a real good look at this.....no?

[glhs875]

I mean a 655 that has been cut to show the cross section of the intake, and more importantly, the exhaust ports. Cut right down the center so you can see the entire shape, floor, roof ect. (I don't know how else to describe it, though cross section was the appropriate term?)



Something like that of all 3 heads, or/and an XRAY of all 3 heads for comparison would be interesting. Taking the 8V head ports out to this new maximum level really needs a whole new custom intake to feed ports this large. An adapter plate needs to be made and attached to the head with counter sunk bolts that will allow the new intake mount bolts to be moved to a different location to allow the removal of the pinchpoint in the mount bolt area that the stock intake runners have, and the injectors could be mounted in the adaptor plate as well to make the building of the custom intake much easier.

[Directconnection]

That is the pic I was talking about, but I was also told that it might not be 100% accurate. If it is, the exhaust port is in BIG trouble!

Rob, this is no time to turtle! Grab all the info and pics you have of the 655 and accept your invite to the party and let's take a real good look at this.....no?

No, that pic is pretty accurate from my findings.

I'm sure Rob has several 655's... so maybe he'd cut one apart for comparison's sake. Yes, this is a "non-arguementative" invite for him to post up.;)

[Shadow]

i remember seeing this on another thread posted by Todd (4 L bodies)
thought id ad it to the thread


http://www.turbo-mopar.com/forums/attachment.php?attachmentid=15886&d=1247153009

Steve, this pic is exactly what I was talking about when I said "cross section".

A cut up section of a 655 head showing this exact view. :nod:

[Directconnection]

I can donate my 445/287 with that exact same cutaway view. I even took another set of runners/chamber and cut the chamber off exposing the thickness of each runner's walls and waterjackets....

[RoadWarrior222]

Which one did Frank cut?

[Shadow]

I can donate my 445/287 with that exact same cutaway view. I even took another set of runners/chamber and cut the chamber off exposing the thickness of each runner's walls and waterjackets....

Prob not a bad idea to get the ball rolling and for comparo, but after all this talk about the 655 I really think it's about time that we take a serious look see, and if someone hasn't cut one up, I think it's about time someone did.

Everything I've posted about my opinion on it is based off the diagram that was posted, and if the real deal is different then that could change things significantly. + I don't want to be down playing something that may deserve more merit than I'm giving it!

[Directconnection]

+ I don't want to be down playing something that may deserve more merit than I'm giving it!

Neither do I, even though Rob thinks differently.

I *thought* the exhaust would flow much worse, but it was about the same as the 782's.... if you look at both my #s on page 1.

I know I could make it flow MUCH better... but by how much? I mean if the short turn was that abrupt..... but what really hurts it is there's nothing under the seat's bottom cut to lay the short turn back the *correct* form. Literally there's such a small amout right after the seat...

[puppet]

Sorry guys, did mean csa ... brain/hand connection switched off.

I know some of the guys remember what Frenchie did with one 782 .. raising the port.* Just doing that would equal the entrance size between castings and hold the improved approach to the valve of the later casting(s) ... if that's what a guy wanted to do. but .. that's waaay bigger than the 44mm valve though. As far as flow velocity is concerned, where does a guy go from there (bowl-throat transition)? Are the function(s) of those areas not important in a turbocharged head? Transitions though out the rpm range would tell the story.

*(I do believe he raised the floors though too. Even further improving approach.)

[puppet]

Rob has a couple of these heads ... Rob has a car or two ... Rob wants the lies to stop ... Rob ... put one on and run it down the track.

[Warren Stramer]

That is the pic I was talking about, but I was also told that it might not be 100% accurate. If it is, the exhaust port is in BIG trouble!?

Agree, I found that changing the ex. port profile, NOT huge size, makes a better performing head (on the track and flow bench)

I made them look like the illustration below right. I dont see how you could get this ex. port shape in a 655 without welding. The 655 intake port I could deal with but I can make a 287/445 intake port exactly the same as the 655 but I wouldnt want to.
Just because you can hog out a intake port to a huge volumn means nothing, the port c/s has to be matched to the available throat diam. and that is where we are limited.

[turbovanman²]

The point was made, the setup is very impressive far from being worked out compared to what he had before.

Maybe, we'll have to see.



Sorry guys, did mean csa ... brain/hand connection switched off.

I know some of the guys remember what Frenchie did with one 782 .. raising the port.* Just doing that would equal the entrance size between castings and hold the improved approach to the valve of the later casting(s) ... if that's what a guy wanted to do. but .. that's waaay bigger than the 44mm valve though. As far as flow velocity is concerned, where does a guy go from there (bowl-throat transition)? Are the function(s) of those areas not important in a turbocharged head? Transitions though out the rpm range would tell the story.

*(I do believe he raised the floors though too. Even further improving approach.)

Yep, on the intake side, I had pics saved, could stick a tennis ball thru, lol.


Agree, I found that changing the ex. port profile, NOT huge size makes a better performing head (on the track and flow bench)

I made them look like the illistration below right. I dont see how you could get this ex. port shape in a 655 without welding. The 655 intake port I could deal with but I can make a 287/445 intake port exactly the same as the 655 but I woudnt want to.
Just because you can hog out a intake port to a huge volumn means nothing, the port c/s has to be matched to the available throat diam. and that is where we are limited.

Very interesting. Thanks.

[Shadow]

Rob has a couple of these heads ... Rob has a car or two ... Rob wants the lies to stop ... Rob ... put one on and run it down the track.

At this point I don't think that even enters into the eq. Anybody could run one of these heads and have great results, I don't think anyone here is desputing that, and THAT'S where it get confusing for some!

No one is saying the 655 won't work, just like (I think) No one has said that conicles and PT lifters won't work.

The Q (for me at least) has always been, does any of this work significantly better than the stuff it's being compared too! Because that's how it's been promoted. Not to even be slightly better, but to be a vast improvement over everything else!

So, only back to back dyno or back to back track results are going to really tell the story and it would take someone with the patience and drive to replace Nothing but the cyl head with same cam and valvetrain that the comparo head was running and run it.........not going to happen IMO.

[zin]

....replace Nothing but the cyl head with same cam and valvetrain that the comparo head was running and run it.........not going to happen IMO.

Unfortunately, this wouldn't work. As you change the flow characteristics, the proper intake and cam configurations would change too, making it an unfair test to all but the one that best matches the cam and intake used.

This is where the flow bench has it's place, it can give you an A to B flow rate at X to Y lift... Even then you'd have to settle on valve size, and shrouding can make a bigger valved head flow less... Depending on the port angle even the shape of the valve can have significant effects (tulip vs. flat).

To be accurate, each intake port would need a transition plate with consistent radius for each port entrance, assuming that they wouldn't all be kept to the same dimensions... And the proper size cylinder (bore dia) under the head, and properly centered...

It's easy to see how there can be so many different opinions, change one aspect and significant differences can be seen.

Since, it appears that all of our heads flow in close proximity to each other, many of these variables could skew the numbers in favor of one or the other by "accident"/luck...

Of course, not having as much history with modding our heads, I'll defer to those who do have a longer history... at least until I've done it myself!;)

Mike

[zin]

An adapter plate needs to be made and attached to the head with counter sunk bolts that will allow the new intake mount bolts to be moved to a different location to allow the removal of the pinchpoint in the mount bolt area that the stock intake runners have, and the injectors could be mounted in the adapter plate as well to make the building of the custom intake much easier.

The term you are looking for is a "sub-plate", to do just as you describe.

And you are right on the money, IMHO...

Mike

[Shadow]

One thing about me: I never, ever lie.... and I have an uber *crazy* intolerance for ones that do

Making a statement like this can be a very slippery slope, but I believe I know what your trying to say so I can cut some slac and LIG.

The amount of consistency it take to "Never lie" in this life is rare indeed and takes a self discipline that is "Christ like".

Safer to say that to the best of your knowlege and as much as possible you do your best Not to lie. ;)

[Shadow]

Unfortunately, this wouldn't work. As you change the flow characteristics, the proper intake and cam configurations would change too, making it an unfair test to all but the one that best matches the cam and intake used.
Mike

As long as the combustion chamber was the same on both heads, and the test was being done on a 500+WHP 8v that had an intake that could readily supply either head I don't see a problem.

Although, if your refuring to the 655 needing a different shaped intake because of the port shape, then I see where your coming from.

I guess another Q could be; is the port size justified concidering the size of valve you can fit on the intake side?

[zin]

I guess another Q could be; is the port size justified considering the size of valve you can fit on the intake side?

THAT is an excellent question!...

I've got a bug to put all my Chaffey College Racecar Technology notes into a cohesive volume, once I do, I'll try to build a spread sheet that would lay out the various port dimensions for a "perfect" port/head. As well as intake runners... Then we can see just how screwed we really are!:lol::lol:

Seems like right now the #1 limitation, or at least the one that will dictate max safe RPM, will be the mean piston speed the rods can deal with... Anyone know what the strongest OE rod will take in ft/sec? Assuming quality forged pistons... 4k ft/sec?

Mike

[Shadow]

THAT is an excellent question!...

I've got a bug to put all my Chaffey College Racecar Technology notes into a cohesive volume, once I do, I'll try to build a spread sheet that would lay out the various port dimensions for a "perfect" port/head. As well as intake runners... Then we can see just how screwed we really are!:lol::lol:

Seems like right now the #1 limitation, or at least the one that will dictate max safe RPM, will be the mean piston speed the rods can deal with... Anyone know what the strongest OE rod will take in ft/sec? Assuming quality forged pistons... 4k ft/sec?

Mike

Taking everything into account, that you have a proper intake, equil L header and all supporting mods, the head would deff be the next limitation IMO. Fix the head to go 8000rpm and I think the mtr follows.(2.2 anyways)

Above that you may need to mess with rod ratio as you aproch 9000+ rpm, but I think the stock geometry will go 8000rpm without too much difficulty.

[puppet]

I guess another Q could be; is the port size justified concidering the size of valve you can fit on the intake side?To sort of expand on this notion .. it's also a fact that what's being compared is a head off a sub-100hp combo ..... and now arguing about being able to wring upwards of 500hp out of it.

hmmm .. why didn't this casting make the turbocharged engine cut?

[glhs875]

Just because you can hog out a intake port to a huge volumn means nothing, the port c/s has to be matched to the available throat diam. and that is where we are limited.




That is a very good point! With a 44mm intake valve on a 2.2, it will take a camshaft with .600+ lift to stay below the mach index choke point of .550 if a person wants to turn 8000rpm or above and make power! No matter what the intake port or anything else is like. The intake valve diameter and even more so the throat area is definitely a limiting factor!!! With a .430 lift cam you can forget it!!

[John B]

Safer to say that to the best of your knowlege and as much as possible you do your best Not to lie. ;)

If your wife asks you if she is as pretty as she was 20 years ago, the answer is "yes!". God made woman so he will understand...:nod:

[Warren Stramer]

That is a very good point! with a 44mm intake valve on a 2.2, it will take a camshaft with .600+ lift to stay below the mach index choke point of .550 if a person wants to turn 8000rpm or above and make power! No matter what the intake port or anything else is like. The intake valve diameter and even more so the throat area is defintely a limiting factor!!! With a .430 lift cam you can forget it!!


Which reminds me of this..................Also known as 'sonic choke'. Also google De Lavel nozzle. interesting reading, but hard for me to follow.




Choked flow
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Choked flow is a fluid dynamic condition associated with the Venturi effect. When a flowing fluid at a given pressure and temperature passes through a restriction (such as the throat of a convergent-divergent nozzle or a valve in a pipe) into a lower pressure environment, because of conservation of mass the fluid velocity must increase for initially subsonic upstream conditions as it flows through the smaller cross-sectional area of the restriction. At the same time, the Venturi effect causes the static pressure, and therefore the density, to decrease. Choked flow is a limiting condition which occurs when the mass flow rate will not increase with a further decrease in the downstream pressure environment while upstream pressure is fixed.

For homogeneous fluids, the physical point at which the choking occurs for adiabatic conditions is when the exit plane velocity is at sonic conditions or at a Mach number of 1.[1][2][3] The mass flow rate can still be increased by increasing the upstream pressure, or by decreasing the upstream temperature.

The choked flow of gases is useful in many engineering applications because the mass flow rate is independent of the downstream pressure, depending only on the temperature and pressure on the upstream side of the restriction. Under choked conditions, valves and calibrated orifice plates can be used to produce a particular mass flow rate.

If the fluid is a liquid, a different type of limiting condition (also known as choked flow) occurs when the Venturi effect acting on the liquid flow through the restriction decreases the liquid pressure to below that of the liquid vapor pressure at the prevailing liquid temperature. At that point, the liquid will partially flash into bubbles of vapor and the subsequent collapse of the bubbles causes cavitation. Cavitation is quite noisy and can be sufficiently violent to physically damage valves, pipes and associated equipment. In effect, the vapor bubble formation in the restriction limits the flow from increasing any further.[4][5]

Contents [hide]
1 Mass flow rate of a gas at choked conditions
1.1 Choking in change of cross section flow
2 Thin-plate orifices
3 Minimum pressure ratio required for choked flow to occur
4 See also
5 References
6 External links


[edit] Mass flow rate of a gas at choked conditions
All gases flow from upstream higher pressure sources to downstream lower pressure sources. There are several situations in which choked flow occurs, such as the change of cross section in a de Laval nozzle or flow through an orifice plate.

[edit] Choking in change of cross section flow
Assuming ideal gas behavior, steady state choked flow occurs when the ratio of the absolute upstream pressure to the absolute downstream pressure is equal to or greater than [ ( k + 1 ) / 2 ] k / ( k - 1 ), where k is the specific heat ratio of the gas (sometimes called the isentropic expansion factor and sometimes denoted as γ ).

For most gases, k ranges from 1.09 (e.g. butane) to 1.67 (monatomic gases), and therefore [ ( k + 1 ) / 2 ] k / ( k - 1 ) ranges from 1.7 to about 2.1 ... which means that choked flow usually occurs when the absolute source vessel pressure is at least 1.7 to 2.1 times as high as the absolute downstream pressure.

When the gas velocity is choked, the equation for the mass flow rate in SI metric units is: [1][2][3][6]



=



where the quantities are defined in the table below. If the density ρ is not known directly, then it is useful to eliminate it using the Ideal gas law corrected for the real gas compressibility:



=



so that the mass flow rate is primarily dependent on the cross-sectional area A of the hole and the upstream pressure P, and only weakly dependent on the temperature T. The rate does not depend on the downstream pressure at all. All other terms are constants that depend only on the composition of the material in the flow. Although the gas velocity reaches a maximum and becomes choked, the mass flow rate is not choked. The mass flow rate can still be increased if the upstream pressure is increased.

where:
= mass flow rate, kg/s
C = discharge coefficient, dimensionless
A = discharge hole cross-sectional area, m²
k = cp/cv of the gas
cp = specific heat of the gas at constant pressure
cv = specific heat of the gas at constant volume
ρ = real gas density at P and T, kg/m³
P = absolute upstream pressure of the gas, Pa
M = the gas molecular mass, kg/kmole (also known as the molecular weight)
R = Universal gas law constant = 8314.5 (N·m) / (kmole·K)
T = absolute upstream temperature of the gas, K
Z = the gas compressibility factor at P and T, dimensionless

The above equations calculate the steady state mass flow rate for the pressure and temperature existing in the upstream pressure source.

If the gas is being released from a closed high-pressure vessel, the above steady state equations may be used to approximate the initial mass flow rate. Subsequently, the mass flow rate will decrease during the discharge as the source vessel empties and the pressure in the vessel decreases. Calculating the flow rate versus time since the initiation of the discharge is much more complicated, but more accurate. Two equivalent methods for performing such calculations are explained and compared online.[7]

The technical literature can be very confusing because many authors fail to explain whether they are using the universal gas law constant R which applies to any ideal gas or whether they are using the gas law constant Rs which only applies to a specific individual gas. The relationship between the two constants is Rs = R / M.

Notes:


For any ideal gas, Z = 1
kmole = 1000 moles
[edit] Thin-plate orifices
The flow of real gases through thin-plate orifices never becomes fully choked. The mass flow rate through the orifice continues to increase as the downstream pressure is lowered to a perfect vacuum, though the mass flow rate increases slowly as the downstream pressure is reduced below the critical pressure.[8] Cunningham (1951) first drew attention to the fact that choked flow will not occur across a standard, thin, square-edged orifice.[9] [10]

[edit] Minimum pressure ratio required for choked flow to occur
The minimum pressure ratios required for choked conditions to occur (when some typical industrial gases are flowing) are presented in Table 1. The ratios were obtained using the criteria that choked flow occurs when the ratio of the absolute upstream pressure to the absolute downstream pressure is equal to or greater than [ ( k + 1 ) / 2 ] k / ( k - 1 ) , where k is the specific heat ratio of the gas. The minimum pressure ratio may be understood as the ratio between the upstream pressure and the pressure at the nozzle throat when the gas is traveling at Mach 1; if the upstream pressure is too low compared to the downstream pressure, sonic flow cannot occur at the throat.



Table 1 Gas k = cp/cv Minimum
Pu/Pd
required for
choked flow
Hydrogen 1.410 1.899
Methane 1.307 1.837
Propane 1.131 1.729
Butane 1.096 1.708
Ammonia 1.310 1.838
Chlorine 1.355 1.866
Sulfur dioxide 1.290 1.826
Carbon monoxide 1.404 1.895

Notes:

Pu = absolute upstream gas pressure
Pd = absolute downstream gas pressure
k values obtained from:
Perry, Robert H. and Green, Don W. (1984). Perry's Chemical Engineers' Handbook (6th Edition ed.). McGraw-Hill Company. ISBN 0-07-049479-7.
Phillips Petroleum Company (1962). Reference Data For Hydrocarbons And Petro-Sulfur Compounds (Second Printing ed.). Phillips Petroleum Company.
[edit] See also
Accidental release source terms includes mass flow rate equations for non-choked gas flows as well.
Orifice plate includes derivation of non-choked gas flow equation.
Laval nozzles are Venturi tubes that produce supersonic gas velocities as the tube and the gas are first constricted and then the tube and gas are expanded beyond the choke plane.
Rocket engine nozzles discusses how to calculate the exit velocity from nozzles used in rocket engines.
Hydraulic jump.
[edit] References
^ a b Perry's Chemical Engineers' Handbook, Sixth Edition, McGraw-Hill Co., 1984.
^ a b Handbook of Chemical Hazard Analysis Procedures, Appendix B, Federal Emergency Management Agency, U.S. Dept. of Transportation, and U.S. Environmental Protection Agency, 1989. Handbook of Chemical Hazard Analysis, Appendix B Click on PDF icon, wait and then scroll down to page 391 of 520 PDF pages.
^ a b Methods For The Calculation Of Physical Effects Due To Releases Of Hazardous Substances (Liquids and Gases), PGS2 CPR 14E, Chapter 2, The Netherlands Organization Of Applied Scientific Research, The Hague, 2005. PGS2 CPR 14E
^ Valve Sizing Calculations Scroll to discussion of liquid flashing and cavitation.
^ Control Valve Handbook Search document for "Choked".
^ Risk Management Program Guidance For Offsite Consequence Analysis, U.S. EPA publication EPA-550-B-99-009, April 1999. Guidance for Offsite Consequence Analysis
^ Calculating Accidental Release Rates From Pressurized Gas Systems
^ Section 3 -- Choked Flow
^ Forum post on 1 Apr 03 19:37
^ Richard W. Miller (1996). Flow Measurement Engineering Handbook (Third Edition ed.). McGraw Hill. ISBN 0-07-042366-0.
[edit] External links
Additional accidental release source terms
Choked flow of gases
Development of source emission models
Retrieved from "http://en.wikipedia.org/wiki/Choked_flow"
Categories: Fluid dynamics | Aerodynamics | Chemical engineering

[Shadow]

If your wife asks you if she is as pretty as she was 20 years ago, the answer is "yes!". God made woman so he will understand...:nod:

Good example! Prob sounds like I'm splitting hairs over stuff like this, but life has circumstances that at times are beyond our control. I try to keep my word to everyone and in every instance, but there are times when priorities arise and I'm taken aside until they're resolved. During those times, if I've given my word to someone concerning a "lesser" matter, it becomes broken.

I never ment to break it, and when I gave it, I had every good intention to keep it, but life sometimes gets in the way.

But like I said, I know what Steve ment, I'm sure he's talking about ppl who knowingly lie and decieve regularly for they're own benifit, which is a whole different story.


Which reminds me of this..................Also known as 'sonic choke'. Also google De Lavel nozzle. interesting reading, but hard for me to follow.




Choked flow
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Choked flow is a fluid dynamic condition associated with the Venturi effect. When a flowing fluid at a given pressure and temperature passes through a restriction (such as the throat of a convergent-divergent nozzle or a valve in a pipe) into a lower pressure environment, because of conservation of mass the fluid velocity must increase for initially subsonic upstream conditions as it flows through the smaller cross-sectional area of the restriction. At the same time, the Venturi effect causes the static pressure, and therefore the density, to decrease. Choked flow is a limiting condition which occurs when the mass flow rate will not increase with a further decrease in the downstream pressure environment while upstream pressure is fixed.

For homogeneous fluids, the physical point at which the choking occurs for adiabatic conditions is when the exit plane velocity is at sonic conditions or at a Mach number of 1.[1][2][3] The mass flow rate can still be increased by increasing the upstream pressure, or by decreasing the upstream temperature.

The choked flow of gases is useful in many engineering applications because the mass flow rate is independent of the downstream pressure, depending only on the temperature and pressure on the upstream side of the restriction. Under choked conditions, valves and calibrated orifice plates can be used to produce a particular mass flow rate.

If the fluid is a liquid, a different type of limiting condition (also known as choked flow) occurs when the Venturi effect acting on the liquid flow through the restriction decreases the liquid pressure to below that of the liquid vapor pressure at the prevailing liquid temperature. At that point, the liquid will partially flash into bubbles of vapor and the subsequent collapse of the bubbles causes cavitation. Cavitation is quite noisy and can be sufficiently violent to physically damage valves, pipes and associated equipment. In effect, the vapor bubble formation in the restriction limits the flow from increasing any further.[4][5]

Contents [hide]
1 Mass flow rate of a gas at choked conditions
1.1 Choking in change of cross section flow
2 Thin-plate orifices
3 Minimum pressure ratio required for choked flow to occur
4 See also
5 References
6 External links


[edit] Mass flow rate of a gas at choked conditions
All gases flow from upstream higher pressure sources to downstream lower pressure sources. There are several situations in which choked flow occurs, such as the change of cross section in a de Laval nozzle or flow through an orifice plate.

[edit] Choking in change of cross section flow
Assuming ideal gas behavior, steady state choked flow occurs when the ratio of the absolute upstream pressure to the absolute downstream pressure is equal to or greater than [ ( k + 1 ) / 2 ] k / ( k - 1 ), where k is the specific heat ratio of the gas (sometimes called the isentropic expansion factor and sometimes denoted as γ ).

For most gases, k ranges from 1.09 (e.g. butane) to 1.67 (monatomic gases), and therefore [ ( k + 1 ) / 2 ] k / ( k - 1 ) ranges from 1.7 to about 2.1 ... which means that choked flow usually occurs when the absolute source vessel pressure is at least 1.7 to 2.1 times as high as the absolute downstream pressure.

When the gas velocity is choked, the equation for the mass flow rate in SI metric units is: [1][2][3][6]



=



where the quantities are defined in the table below. If the density ρ is not known directly, then it is useful to eliminate it using the Ideal gas law corrected for the real gas compressibility:



=



so that the mass flow rate is primarily dependent on the cross-sectional area A of the hole and the upstream pressure P, and only weakly dependent on the temperature T. The rate does not depend on the downstream pressure at all. All other terms are constants that depend only on the composition of the material in the flow. Although the gas velocity reaches a maximum and becomes choked, the mass flow rate is not choked. The mass flow rate can still be increased if the upstream pressure is increased.

where:
= mass flow rate, kg/s
C = discharge coefficient, dimensionless
A = discharge hole cross-sectional area, m²
k = cp/cv of the gas
cp = specific heat of the gas at constant pressure
cv = specific heat of the gas at constant volume
ρ = real gas density at P and T, kg/m³
P = absolute upstream pressure of the gas, Pa
M = the gas molecular mass, kg/kmole (also known as the molecular weight)
R = Universal gas law constant = 8314.5 (N·m) / (kmole·K)
T = absolute upstream temperature of the gas, K
Z = the gas compressibility factor at P and T, dimensionless

The above equations calculate the steady state mass flow rate for the pressure and temperature existing in the upstream pressure source.

If the gas is being released from a closed high-pressure vessel, the above steady state equations may be used to approximate the initial mass flow rate. Subsequently, the mass flow rate will decrease during the discharge as the source vessel empties and the pressure in the vessel decreases. Calculating the flow rate versus time since the initiation of the discharge is much more complicated, but more accurate. Two equivalent methods for performing such calculations are explained and compared online.[7]

The technical literature can be very confusing because many authors fail to explain whether they are using the universal gas law constant R which applies to any ideal gas or whether they are using the gas law constant Rs which only applies to a specific individual gas. The relationship between the two constants is Rs = R / M.

Notes:


For any ideal gas, Z = 1
kmole = 1000 moles
[edit] Thin-plate orifices
The flow of real gases through thin-plate orifices never becomes fully choked. The mass flow rate through the orifice continues to increase as the downstream pressure is lowered to a perfect vacuum, though the mass flow rate increases slowly as the downstream pressure is reduced below the critical pressure.[8] Cunningham (1951) first drew attention to the fact that choked flow will not occur across a standard, thin, square-edged orifice.[9] [10]

[edit] Minimum pressure ratio required for choked flow to occur
The minimum pressure ratios required for choked conditions to occur (when some typical industrial gases are flowing) are presented in Table 1. The ratios were obtained using the criteria that choked flow occurs when the ratio of the absolute upstream pressure to the absolute downstream pressure is equal to or greater than [ ( k + 1 ) / 2 ] k / ( k - 1 ) , where k is the specific heat ratio of the gas. The minimum pressure ratio may be understood as the ratio between the upstream pressure and the pressure at the nozzle throat when the gas is traveling at Mach 1; if the upstream pressure is too low compared to the downstream pressure, sonic flow cannot occur at the throat.



Table 1 Gas k = cp/cv Minimum
Pu/Pd
required for
choked flow
Hydrogen 1.410 1.899
Methane 1.307 1.837
Propane 1.131 1.729
Butane 1.096 1.708
Ammonia 1.310 1.838
Chlorine 1.355 1.866
Sulfur dioxide 1.290 1.826
Carbon monoxide 1.404 1.895

Notes:

Pu = absolute upstream gas pressure
Pd = absolute downstream gas pressure
k values obtained from:
Perry, Robert H. and Green, Don W. (1984). Perry's Chemical Engineers' Handbook (6th Edition ed.). McGraw-Hill Company. ISBN 0-07-049479-7.
Phillips Petroleum Company (1962). Reference Data For Hydrocarbons And Petro-Sulfur Compounds (Second Printing ed.). Phillips Petroleum Company.
[edit] See also
Accidental release source terms includes mass flow rate equations for non-choked gas flows as well.
Orifice plate includes derivation of non-choked gas flow equation.
Laval nozzles are Venturi tubes that produce supersonic gas velocities as the tube and the gas are first constricted and then the tube and gas are expanded beyond the choke plane.
Rocket engine nozzles discusses how to calculate the exit velocity from nozzles used in rocket engines.
Hydraulic jump.
[edit] References
^ a b Perry's Chemical Engineers' Handbook, Sixth Edition, McGraw-Hill Co., 1984.
^ a b Handbook of Chemical Hazard Analysis Procedures, Appendix B, Federal Emergency Management Agency, U.S. Dept. of Transportation, and U.S. Environmental Protection Agency, 1989. Handbook of Chemical Hazard Analysis, Appendix B Click on PDF icon, wait and then scroll down to page 391 of 520 PDF pages.
^ a b Methods For The Calculation Of Physical Effects Due To Releases Of Hazardous Substances (Liquids and Gases), PGS2 CPR 14E, Chapter 2, The Netherlands Organization Of Applied Scientific Research, The Hague, 2005. PGS2 CPR 14E
^ Valve Sizing Calculations Scroll to discussion of liquid flashing and cavitation.
^ Control Valve Handbook Search document for "Choked".
^ Risk Management Program Guidance For Offsite Consequence Analysis, U.S. EPA publication EPA-550-B-99-009, April 1999. Guidance for Offsite Consequence Analysis
^ Calculating Accidental Release Rates From Pressurized Gas Systems
^ Section 3 -- Choked Flow
^ Forum post on 1 Apr 03 19:37
^ Richard W. Miller (1996). Flow Measurement Engineering Handbook (Third Edition ed.). McGraw Hill. ISBN 0-07-042366-0.
[edit] External links
Additional accidental release source terms
Choked flow of gases
Development of source emission models
Retrieved from "http://en.wikipedia.org/wiki/Choked_flow"
Categories: Fluid dynamics | Aerodynamics | Chemical engineering

We're getting into it now! ROB, you have a perfect opportunity to join this discussion.

IF you have something to say, say it and let's see where it goes.

[puppet]

Warren ... I gather that all your head development has been around the 445/287 casting(s). Have you done any work with the 782 ... if not, how come? Was it the initial 10 point flow advantage to start with (stock) that has kept you with the bathtub designed heads?

I ask this because I believe there are certain advantages to the 782 that are perhaps often overlooked. So, could a guy make even more power w/the fastburn casting? Let's look at the differences between the two castings for a second.

The 782 has a smaller chamber ... less surface area which is most often considered an advantage to charge burn rate/efficiency.

Another is the option for a slight increase in CR. From what I know/read a higher CR'ed engine drops pressure within the cylinder at a faster rate (ATDC) which in turn would allow the exhaust valve opening event to be advanced without any real penalty. I'd think this would be an advantage to a turbocharged application in that the increased duration of the exhaust event would allow a smaller valve here and in so doing, allow more space for the even larger intake valve. A huge part of such a combo would be designing a suitable camshaft to take advantage of the heads optimizations.

[Aries_Turbo]

Which one did Frank cut?

i dont think he cut a 8v head. i know he cut up a 3.0L head when he wanted to do a turbo 3.0L

i believe carl buchbinder cut a 782 years ago but his site has been down for quite some time.

Brian

[Aries_Turbo]

http://web.archive.org/web/20040610153132/www.omniturbo.com/Turbo+Mopars+Home.htm

heres a 782 on carls old site.

Brian

[RoadWarrior222]

i dont think he cut a 8v head. i know he cut up a 3.0L head when he wanted to do a turbo 3.0L

I was pretty sure he did an 8v head as well as the 3.0 head. Last I knew it was up in the gallery somewhere, but it was a b!tch to search.

[Warren Stramer]

Warren ... I gather that all your head development has been around the 445/287 casting(s). Have you done any work with the 782 ... if not, how come? Was it the initial 10 point flow advantage to start with (stock) that has kept you with the bathtub designed heads?
No, Ive not done a 782 for a few reasons. First, I had a source for new G castings, Second, I dont like the intake port but I could work with that. Third, and most importantly to me anyway is that once you unshroud the valves and make the chamber workable you have NO squish area left, only a very little at the 'widows peak' area. (like the photo below that someone posted, as compared to my newest G chamber)
I like the shallow chamber of the 782 but that is about all. The smaller chamber you talk about is gone once you work it over. Most of the 782's attributes that make it 'swirl' are no longer there. after you make it work right. But I must say, this is just my opinion from what I observe. I do think that I could make one work just fine if I had to. Obviously it can be done, Steve Menegon makes them work very well.


I ask this because I believe there are certain advantages to the 782 that are perhaps often overlooked. So, could a guy make even more power w/the fastburn casting? Let's look at the differences between the two castings for a second.

The 782 has a smaller chamber ... less surface area which is most often considered an advantage to charge burn rate/efficiency.

See above.


Another is the option for a slight increase in CR. From what I know/read a higher CR'ed engine drops pressure within the cylinder at a faster rate (ATDC) which in turn would allow the exhaust valve opening event to be advanced without any real penalty. I'd think this would be an advantage to a turbocharged application in that the increased duration of the exhaust event would allow a smaller valve here and in so doing, allow more space for the even larger intake valve. A huge part of such a combo would be designing a suitable camshaft to take advantage of the heads optimizations.
I agree with that, I'm already doing that with the G head. I'm using a +1mm exhaust (35.8mm) and a 44mm intake. Any larger than that on the intake caused big problems on the cyl. wall side.
My solid roller cam has over 300 degrees@.006 duration, intake and exhaust, .605 valve lift.

Once you work over the 782 intake port to the right dimensions you have basically a G port. see pics. All just my opinions, I'm no engineer.

One more thing, Increasing mechanical CR narrows your tuning window significantly, which is not a problem if you never make tuning mistakes, I dont have that much confidence in my tuning yet.

[glhs875]

This thread is getting good now!! I opened the can of worms!!

[BadAssPerformance]

i dont think he cut a 8v head. i know he cut up a 3.0L head when he wanted to do a turbo 3.0L

i believe carl buchbinder cut a 782 years ago but his site has been down for quite some time.

Brian

Russ archived the head pics in the KC a while ago.. just need the 655 added:

http://www.turbo-mopar.com/forums/vbarticles.php?do=article&articleid=84

[GLHNSLHT2]

We're getting into it now! ROB, you have a perfect opportunity to join this discussion.

IF you have something to say, say it and let's see where it goes.


I don't think Rob will be around for a bit. I recieved a txt from him this morning saying something about his HD crashing from d'loading too much Porn and contracting some sort of virus from it


:D

[puppet]

Third, and most importantly to me anyway is that once you unshroud the valves and make the chamber workable you have NO squish area left, only a very little at the 'widows peak' area. (like the photo below that someone posted, as compared to my newest G chamber) Brings in another point. I know you've seen the talk pro/con about squish in a turbocharged application. Respected porters saying it's unwanted and making better power as a result. Not sure what to make of that myself but I find it interesting that these guys regard squish w/boost as they do.

EDIT: I still have this impression that swirl is induced by the bowl area in the 782. ... not the chamber.

[crusty shadow]

ive been watching this thread degrade from a 655 flow test thread to a bash the 655 thread.
i just happen to have a 655 head thats nearly brand new- doesnt even look like its ever been run. i can stick my finger in the exhaust port and i dont feel any 90* turns in there. i do feel the emissions hump the pope refers to.
its pretty obvious the pope is the "655 go-to guy" he has mre first hand experience with that casting than anyone else here, so i tend to trust his advice over others concerning the head.
the general concensus ive gathered from all his posts in this and other threads is that the 655 needs little to no work on the intake and fairly mild work on the exhaust.
get the head rocking and you need to seriously upgrade the intake manifold or its a waste of time. isnt that true of pretty much any hi flow head no matter what its for?

several times people have said in this thread that its easy to make the 655 kick butt. all the others require extensive porting / welding to match its flow. that tells me this is hidden treasure. most of us dont have flowbenches, tig welders or the other stuff you need to do that kind of work. i dont know about you but i dont like to work harder than i have to.

i'll be sending my head to the pope next month so he can match the ports to work with the oversized valves i have ( i forget what size , i'll look when i get home) i'll have him post the #'s when its done, and we'll see how it works in a car sometime next year when its together and making passes.

[turbovanman²]

Unfortunately, this wouldn't work. As you change the flow characteristics, the proper intake and cam configurations would change too, making it an unfair test to all but the one that best matches the cam and intake used.

This is where the flow bench has it's place, it can give you an A to B flow rate at X to Y lift... Even then you'd have to settle on valve size, and shrouding can make a bigger valved head flow less... Depending on the port angle even the shape of the valve can have significant effects (tulip vs. flat).

To be accurate, each intake port would need a transition plate with consistent radius for each port entrance, assuming that they wouldn't all be kept to the same dimensions... And the proper size cylinder (bore dia) under the head, and properly centered...

It's easy to see how there can be so many different opinions, change one aspect and significant differences can be seen.

Since, it appears that all of our heads flow in close proximity to each other, many of these variables could skew the numbers in favor of one or the other by "accident"/luck...

Of course, not having as much history with modding our heads, I'll defer to those who do have a longer history... at least until I've done it myself!;)

Mike

I don't agree, if you have a high HP engine with good manifolds, then swapping heads will be a good thing or bad thing. Look at Warren's new head and cam combo, for a good example.


Warren ... I gather that all your head development has been around the 445/287 casting(s). Have you done any work with the 782 ... if not, how come? Was it the initial 10 point flow advantage to start with (stock) that has kept you with the bathtub designed heads?

I ask this because I believe there are certain advantages to the 782 that are perhaps often overlooked. So, could a guy make even more power w/the fastburn casting? Let's look at the differences between the two castings for a second.

The 782 has a smaller chamber ... less surface area which is most often considered an advantage to charge burn rate/efficiency.

Another is the option for a slight increase in CR. From what I know/read a higher CR'ed engine drops pressure within the cylinder at a faster rate (ATDC) which in turn would allow the exhaust valve opening event to be advanced without any real penalty. I'd think this would be an advantage to a turbocharged application in that the increased duration of the exhaust event would allow a smaller valve here and in so doing, allow more space for the even larger intake valve. A huge part of such a combo would be designing a suitable camshaft to take advantage of the heads optimizations.

I know I keep saying this but SMP said the swirl will make more power comparable G-head, something about timing and the swirl really helps but maybe with Warren and others porting and changing the chamber on a G head, that changes?


Russ archived the head pics in the KC a while ago.. just need the 655 added:

http://www.turbo-mopar.com/forums/vbarticles.php?do=article&articleid=84

I'll get the pics of my cut TIII head when I find my camera battery, :o


Brings in another point. I know you've seen the talk pro/con about squish in a turbocharged application. Respected porters saying it's unwanted and making better power as a result. Not sure what to make of that myself but I find it interesting that these guys regard squish w/boost as they do.

Could be, I removed mine on my TIII head and feels just as strong and I've taken a whack of timing out. Now I've been bashed over this and I had reasons for doing it, still need to hit the dyno and see if its a dismal failure or it actually worked.


ive been watching this thread degrade from a 655 flow test thread to a bash the 655 thread.
i just happen to have a 655 head thats nearly brand new- doesnt even look like its ever been run. i can stick my finger in the exhaust port and i dont feel any 90* turns in there. i do feel the emissions hump the pope refers to.
its pretty obvious the pope is the "655 go-to guy" he has mre first hand experience with that casting than anyone else here, so i tend to trust his advice over others concerning the head.
the general concensus ive gathered from all his posts in this and other threads is that the 655 needs little to no work on the intake and fairly mild work on the exhaust.
get the head rocking and you need to seriously upgrade the intake manifold or its a waste of time. isnt that true of pretty much any hi flow head no matter what its for?

several times people have said in this thread that its easy to make the 655 kick butt. all the others require extensive porting / welding to match its flow. that tells me this is hidden treasure. most of us dont have flowbenches, tig welders or the other stuff you need to do that kind of work. i dont know about you but i dont like to work harder than i have to.

i'll be sending my head to the pope next month so he can match the ports to work with the oversized valves i have ( i forget what size , i'll look when i get home) i'll have him post the #'s when its done, and we'll see how it works in a car sometime next year when its together and making passes.

No offence but did you actually read this thread, its more than fingers in a port, :p

[puppet]

ive been watching this thread degrade from a 655 flow test thread to a bash the 655 thread.
i just happen to have a 655 head thats nearly brand new- doesnt even look like its ever been run. i can stick my finger in the exhaust port and i dont feel any 90* turns in there. i do feel the emissions hump the pope refers to.
its pretty obvious the pope is the "655 go-to guy" he has mre first hand experience with that casting than anyone else here, so i tend to trust his advice over others concerning the head.
the general concensus ive gathered from all his posts in this and other threads is that the 655 needs little to no work on the intake and fairly mild work on the exhaust.
get the head rocking and you need to seriously upgrade the intake manifold or its a waste of time. isnt that true of pretty much any hi flow head no matter what its for?

several times people have said in this thread that its easy to make the 655 kick butt. all the others require extensive porting / welding to match its flow. that tells me this is hidden treasure. most of us dont have flowbenches, tig welders or the other stuff you need to do that kind of work. i dont know about you but i dont like to work harder than i have to.

i'll be sending my head to the pope next month so he can match the ports to work with the oversized valves i have ( i forget what size , i'll look when i get home) i'll have him post the #'s when its done, and we'll see how it works in a car sometime next year when its together and making passes.The part in bold is all that really matters in the end. Talk is cheap ... and almost as important as flow numbers ... to me anyway.

[zin]

The part in bold is all that really matters in the end. Talk is cheap ... and almost as important as flow numbers ... to me anyway.

Something I think we can all agree upon, is results... Not that it would end any controversy, but results are results!

Mike

[Warren Stramer]

Brings in another point. I know you've seen the talk pro/con about squish in a turbocharged application. Respected porters saying it's unwanted and making better power as a result. Not sure what to make of that myself but I find it interesting that these guys regard squish w/boost as they do.

EDIT: I still have this impression that swirl is induced by the bowl area in the 782. ... not the chamber.

My thoughts on that are you can have too much squish on a turbo engine or none, or you can have just the right amount. It depends on dynamic CR and fuel.
On our engines with dished pistons and just a narrow squish band around the perimeter of the piston crown there really isnt alot to begin with but again with the swirl chamber once unshrouded you have basically none. I want SOME around the nether regions of the bore where detonation is most likely to develop.

[Directconnection]

i can stick my finger in the exhaust port and i dont feel any 90* turns in there. i do feel the emissions hump the pope refers to.

No disrespect... but you can't notice it because you must not really have a firm grasp on the subject, hence why you're sending your's off to thepope. The difference is night and day.

I am certain Menegan can work wonders with the 655, as can a few others that *I* would be sending the head to as they have a much better cylinder head porting rep and experience. Ex:Steve cut his teeth with one of THE best head porters of the time, and his story checks out, too ;)

I'll have more to say and post my pix of the cut g-head soon, but I am sooo busy these past/next few days here...

BTW: I gotz me '67 'cuda started tonight after sitting for 7-8 years!

[Shadow]

ive been watching this thread degrade from a 655 flow test thread to a bash the 655 thread.
i just happen to have a 655 head thats nearly brand new- doesnt even look like its ever been run. i can stick my finger in the exhaust port and i dont feel any 90* turns in there. i do feel the emissions hump the pope refers to.
its pretty obvious the pope is the "655 go-to guy" he has mre first hand experience with that casting than anyone else here, so i tend to trust his advice over others concerning the head.
the general concensus ive gathered from all his posts in this and other threads is that the 655 needs little to no work on the intake and fairly mild work on the exhaust.
get the head rocking and you need to seriously upgrade the intake manifold or its a waste of time. isnt that true of pretty much any hi flow head no matter what its for?

several times people have said in this thread that its easy to make the 655 kick butt. all the others require extensive porting / welding to match its flow. that tells me this is hidden treasure. most of us dont have flowbenches, tig welders or the other stuff you need to do that kind of work. i dont know about you but i dont like to work harder than i have to.

i'll be sending my head to the pope next month so he can match the ports to work with the oversized valves i have ( i forget what size , i'll look when i get home) i'll have him post the #'s when its done, and we'll see how it works in a car sometime next year when its together and making passes.

Not sure who you think is bashing the 655, all I see some disscussion going on.

I said it was treasure to those exact ppl you described for those exact reasons.

The Q being asked here is wether or not it's THE BEST HEAD PERIOD! (like it's being made out to be)

Like I said earlier, I'm sure it will work well on your car and 99% of the other 8v cars out there. Most don't and won't ever get to a level that your going to notice a big difference.

[Shadow]

I don't think Rob will be around for a bit. I recieved a txt from him this morning saying something about his HD crashing from d'loading too much Porn and contracting some sort of virus from it


:D

Well hopefully he gets it worked out cause seeing him post today in other threads and not in this one gives the impression he's only willing to shoot the S#IT when these no one with the experiance to have a 2 sided conversation with!

[turbovanman²]

Well hopefully he gets it worked out cause seeing him post today in other threads and not in this one gives the impression he's only willing to shoot the S#IT when these no one with the experiance to have a 2 sided conversation with!

Sounds like he got a 655 virus, :lol:

[puppet]

My thoughts on that are you can have too much squish on a turbo engine or none, or you can have just the right amount. It depends on dynamic CR and fuel.
On our engines with dished pistons and just a narrow squish band around the perimeter of the piston crown there really isnt alot to begin with but again with the swirl chamber once unshrouded you have basically none. I want SOME around the nether regions of the bore where detonation is most likely to occur.Ya ... depending on who you ask determines the amount or lack of. What I gathered from the "no-quench" camp (lol) had to do with turbulence, heat, flame speed.

Turbulence produced by the piston squish forcing the mixture toward the center of the chamber. Turbulence which may be a byproduct of turbocharged application making this a wash. Moreover, the point you also make on the amount being combination dependant to start with. What's optimal for a high boost set-up?

Heat ... we make a fair amount more than an N/A application. N/A application operate on the edge of detonation when making best power .. but in cylinder pressures/temps are lower than ours. The use of proper quench in an N/A application cools the crowns well keeping detonation down. The elevated temps in a turbocharged application (crowns/chambers) can cause detonation if they're too close to each other. Using the charge differential temperature to cool things off instead.

Flame speed with tighter quench is elevated. A looser quench works to slow the flame spread. I'd assume this translates into a lower combustion temp as a whole .. helping stave off detonation as a result.

Thanks for your take on it Warren ... good discussion.

[puppet]

Well hopefully he gets it worked out cause seeing him post today in other threads and not in this one gives the impression he's only willing to shoot the S#IT when these no one with the experiance to have a 2 sided conversation with!I think we all agree that Rob is an OK guy ... and nobody here thinks he's an idiot. We're just trying to get away from the notion that head performance or "potential" comes down squarely on flow percentages Rob (pope).

[Shadow]

I think we all agree that Rob is an OK guy ... and nobody here thinks he's an idiot. We're just trying to get away from the notion that head performance or "potential" comes down squarely on flow percentages Rob (pope).

Agreed, which is why I want him to be able to speak up for once while there are other ppl listening who have the experiance to hear what he's saying.

The problem is, Rob took it upon himself to criticize stuff that was beyond his grasp years ago and he needs to get over it. He was wrong about that stuff and it's gotta sting a little now. (I'm assuming he knows better by now, but he'd have to verify that for me)

On the flip side, he's brought a lot of good stuff to the community and has kept a lot of ppl interested in these cars. I for one think that a lot of what he says has merit.

Besides, he's one of the few out there that recognized what was going on with the Charger and promoted the car more than anyone I know! (prob including me! lol)

I'd like to see the past get tossed and see things start fresh. So, fare warning, if Rob comes on let's see a good discussion without the BS that tends to be thrown his way, and that includes your last comment Simon! :D

[Juggy]

I'd like to see the past get tossed and see things start fresh. So, fare warning, if Rob comes on let's see a good discussion without the BS that tends to be thrown his way, and that includes your last comment Simon! :D

as in comments like this....


No disrespect... but you can't notice it because you must not really have a firm grasp on the subject, hence why you're sending your's off to thepope. The difference is night and day.

I am certain Menegan can work wonders with the 655, as can a few others that *I* would be sending the head to as they have a much better cylinder head porting rep and experience. Ex:Steve cut his teeth with one of THE best head porters of the time, and his story checks out, too ;)

I'll have more to say and post my pix of the cut g-head soon, but I am sooo busy these past/next few days here...

BTW: I gotz me '67 'cuda started tonight after sitting for 7-8 years!

[turbovanman²]

Agreed, which is why I want him to be able to speak up for once while there are other ppl listening who have the experiance to hear what he's saying.

The problem is, Rob took it upon himself to criticize stuff that was beyond his grasp years ago and he needs to get over it. He was wrong about that stuff and it's gotta sting a little now. (I'm assuming he knows better by now, but he'd have to verify that for me)

On the flip side, he's brought a lot of good stuff to the community and has kept a lot of ppl interested in these cars. I for one think that a lot of what he says has merit.

Besides, he's one of the few out there that recognized what was going on with the Charger and promoted the car more than anyone I know! (prob including me! lol)

I'd like to see the past get tossed and see things start fresh. So, fare warning, if Rob comes on let's see a good discussion without the BS that tends to be thrown his way, and that includes your last comment Simon! :D

Aww, come on, just having some fun, :lol:

I agree, he brought us conicals albeit the 3.3's suck, :p and PT's, he does have good idea's.

[turbovanman²]

Ya ... depending on who you ask determines the amount or lack of. What I gathered from the "no-quench" camp (lol) had to do with turbulence, heat, flame speed.

Turbulence produced by the piston squish forcing the mixture toward the center of the chamber. Turbulence which may be a byproduct of turbocharged application making this a wash. Moreover, the point you also make on the amount being combination dependant to start with. What's optimal for a high boost set-up?

Heat ... we make a fair amount more than an N/A application. N/A application operate on the edge of detonation when making best power .. but in cylinder pressures/temps are lower than ours. The use of proper quench in an N/A application cools the crowns well keeping detonation down. The elevated temps in a turbocharged application (crowns/chambers) can cause detonation if they're too close to each other. Using the charge differential temperature to cool things off instead.

Flame speed with tighter quench is elevated. A looser quench works to slow the flame spread. I'd assume this translates into a lower combustion temp as a whole .. helping stave off detonation as a result.

Thanks for your take on it Warren ... good discussion.

I found removing my quench pads made it detonation happy, part of it could be my cams. Hmmmmmmm.

[Aries_Turbo]

squish/quench

this guy likes it.

http://www.theoldone.com/articles/the_soft_head_1999/

i have a friend that has been doing this to some of the engines he builds and it works well. turbo subaru engines.

Brian

[turbovanman²]

squish/quench

this guy likes it.

http://www.theoldone.com/articles/the_soft_head_1999/

i have a friend that has been doing this to some of the engines he builds and it works well. turbo subaru engines.

Brian


Nice read.

I should get some new pistons made up with a dome, :eyebrows:

http://www.theoldone.com/articles/the_soft_head_1999/tiny-N4.jpg

http://www.theoldone.com/articles/the_soft_head_1999/tiny-H2.jpg

[Directconnection]

I'd like to see the past get tossed and see things start fresh. So, fare warning, if Rob comes on let's see a good discussion without the BS that tends to be thrown his way, and that includes your last comment Simon! :D

I can agree to try to some open discussion here as long as there's no "know-it-all" attitudes need to apply.

[Directconnection]

Nice read.

I should get some new pistons made up with a dome, :eyebrows:

http://www.theoldone.com/articles/the_soft_head_1999/tiny-N4.jpg

http://www.theoldone.com/articles/the_soft_head_1999/tiny-H2.jpg

I didn't read that one.... in the middle of stuff here with the GF at the moment, but having a dome is NOT a good thing.

On our dyno, talking with the operator/tuner, the larger the dome, the MORE advance you need to overcome the obstructive path that the flame travel is interfered with. Major downside....

[Directconnection]

Aww, come on, just having some fun, :lol:

I agree, he brought us conicals albeit the 3.3's suck, :p and PT's, he does have good idea's.

Conicals and the PTs weren't invented/1st used by Rob as far as I know.

[Directconnection]

as in comments like this....

Ok, you're right as it did come out in an aggressive manner. I guess what I really meant to say was just because it's all one guy really does, doesn't mean he's going to be the best at it.

And the earlier comment of "no disrespecting you" the words were again probably not the best choice, but the intent is true. They still are not aware of an obvious trait of the 655 and admit to no/not much experience porting heads, either (which doesn't make you any less of a person)

[Shadow]

I can agree to try to some open discussion here as long as there's no "know-it-all" attitudes need to apply.

Agreed. So, trap is set....I mean, stage, of course, HeHe :evil:

We'll see what comes of it.

In the mean time...........

































SOMEONE CUT UP A 655! (and post pics!) :eyebrows:

[The Pope]

The problem is, Rob took it upon himself to criticize stuff that was beyond his grasp years ago and he needs to get over it. He was wrong about that stuff and it's gotta sting a little now. (I'm assuming he knows better by now, but he'd have to verify that for me)

I do know better than I did. But I wonder what I was criticizing years ago that has changed today. I openly have admitted over time that exhaust isn't the end all be all I once thought it was. Now if your talking about land speed records People should read Fast Days, I was wrong about that too. I thought Scott Harvey only went 207 one way on salt. He did but I didn't relize a stock "body" 8v turbo 2.2 went 238 MPH at El Mirage untill reading Fast Days. Was wrong about that. Didn't also relize that Scott went 180 MPH with a NA 8v 2.2 either.... But it is hard to find SD racing history.


On the flip side, he's brought a lot of good stuff to the community and has kept a lot of ppl interested in these cars. I for one think that a lot of what he says has merit.

Besides, he's one of the few out there that recognized what was going on with the Charger and promoted the car more than anyone I know! (prob including me! lol)

There are MANY different sport compacts and V6 turbo cars out there being run. How many different types do you all think are out there? Your SC was the second racer to use a real intake, the first one to push a steetable setup and a basically factory head. The first guy to do it did so many other mods you couldn't see the gain. Your SC has been mild on flow and uses a mod that EVERY OTHER COMPACT USES.

This is where I have a problem with people here. Yeah they give me crap about my story's 15 years ago, fine. But they like to use this to tell me that what the rest of the world is doing, doesn't work with turbo Dodges. There are MANY MANY parts out there we can use to better turbo Dodges and bring them up to todays levels if people are willing to try.

The info is out there. There are springs MADE for high ratio rockers, that deal with the problems that come from poor ratios and actuation. Sure you can do the math and use the old style system and it works. But it also takes MORE spring pressure to get the same result. So I did the leg work for Conical springs. Yes the 3.3's are that great, but at that time years ago almost everyone used a stock intake and couldn't use a real cam. Now we live in the world of plenum's, cams are welcome. 3.3's are not, and shortly after I came up with a new parts list for people. Lifters are easy, the 2.2 and the Neon lifter are the same thing basically and Mopar tossed the old design and made new ones. But not for the 2.2, I went around that so we can have the new design. So if you look around and read there is a lot out there to deal with the 2.2 8v top end issue's.

Then comes the heads. I didn't have a sad 80's cut 782 head to test. Only a better one with todays seat and valve work, which matters on the bench. The 655 I tested was from the 80's, the worst valve job I've ever seen. One single 45 on the valves and the seats. The machine that cut the thing made 1/8" tall sharp edge casting cuts. The valves had such a ridge that it looked like a curb. This 655 went up against a very nice redone 782, night and day difference. The low lift flow was great with a dip around .500" lift that went up to .600" for total flow. The head was still gaining flow at .600", I didn't test it farther. Then this thread......

OK lets throw out my opinion on the 655, make believe I never tested it and I don't like the head, what ever. Anyone here ever look at the Buick V6 or the Ford 2.3's? There are others out there but if you look around you will find big port poor flowing head topped engines out there making a lot of power with a turbo. Rob's SC has given many people a taste of what happens when you work at getting more air into an engine. A factory exhaust manifold and a +1 valve head with stock cam isn't flowing very well. But pumping forces by the short block are increasing and forcing more out of the engine. I used to believe that the exhaust mattered most, and it is important but if your not getting the air in your not getting the pumping forces. What if you take the same idea and add more volume to it. Like some of these other engines out there making huge power with poor flowing heads, they have nothing in there favor but BIG ports. I also can add they have been adding big plenum's to these heads for over 20 years. Our hobby believed (most people) that a short runner big plenum intake kills bottom end response and spool up, just 5 years ago....

So yes I like the 782 combustion chamber better (after I cut it). Yes the 655 out of the box looks machined by a 2 year old. But if you have a head with a very nice short turn, big volume runners, and nice big fat bowls. Then the head DOESN'T hurt low lift average flow and should have came with big valves before porting... What can happen? The head doesn't flow worse (on a bench) and has bigger runners to move a higher volume of boost into the engine.

The 655 has the best ports for porting, so big you just add big valves and blend them. Lots of exhaust cutting and straighting out the intake floor.
The 655 flows best before you start porting, and is machined so sad any clown with sand paper can fix one. Where as you better know exactly what your doing for a few years before you touch a 782.
The 655 is the best head to flow past .500" lift. Yeah other big valve heads will flow some more up there. The 655 rounds over .600" where the other heads round off towards .500" lift.

Down sides to the 655, yes there are some.
The intake, custom or really ported 2 piece, a requirement
The ports on the 655 are raised at the gasket and the intake roof is really high. The 655 uses a shorter intake guide than the other heads. This is the worst down side. You run cave man springs and stock lifters with a 655 and a big cam at high RPM and the guides are going to ware really fast on a 655 vs the others. Our guides are too short in any of the heads in my opinion, and the 655 doesn't have much.
Last down side, there aren't many left out there. They are becoming rare. I have one real low mile head I got that sat for over 10 years. I also have a brand new in the Mopar box 655 that has never had valves in it.:D

So we can talk shrouding, yeah the 655 has the same valve issues the rest have. We can talk about the math of what makes an intake work at what RPM. The 1 piece has runners designed in NA equations (14" runners) for 6,000 RPM peak. yeah that little equation has never worked for boost. We can also talk about how the hell anyone is going to feed a 655 correctly. That could be tough, a LW custom intake with a bigger plenum may be the right choice.

[The Pope]

SOMEONE CUT UP A 655! (and post pics!) :eyebrows:

I have a brand new 655 and no body is going to cut it but me, and only in a friendly way lol

[The Pope]

Conicals and the PTs weren't invented/1st used by Rob as far as I know.

I am not the first to use conicals. Some Mopar engineer years ago had some custom made for the 2.2 and liked them. But for the money no body else followed behind him and no body sold a conical for the 2.2. Still today no body sells a spring for a 2.2. But they do sell springs for the magnum and they do sell keepers and retainers for the LS1 Chevy.

PTs were first used by me, Jay was second. And Jay I can tell you believes NOTHING I tell him ever. You two would get a long great. The difference is Jay lives here and I show him what I'm talking about.

Neither are inventions of mine either, I am always looking at new tech as I am not closed minded. Many people stop learning at an age.

[bakes]

Heres a little side track Q has any one tried to run a 6mm guide and valve stem in one of this head?

[The Pope]

The part in bold is all that really matters in the end. Talk is cheap ... and almost as important as flow numbers ... to me anyway.


http://www.youtube.com/watch?v=9o15EALghp0"]http://www.youtube.com/watch?v=9o15EALghp0

an example of an engineer on a bike he designed that he doesn't actually race....

I have built cars for many years and most aren't cars I drive. I have seen guys with 25 PSI and hybrid turbos run mid 15s. I've also seen a log T1 GLH's run 12's. The ET often is an example of the car and the cars setup to race. Slowes Shadow is an example of a car built to race, and his car makes the ET's. ANY car I build for my self is a street car first, period. My cars right now weigh more than stock and are built with bigger brakes, sway bars and so on for autocross and road course driving. 2 of these cars will have good power at least but neither will be setup for drag racing. So am I going to get done and beat some low ETs with a road course car? Hardly, my goal is high WHP with low boost with 8v's. That you can look for from me. At this time it is impossible, some times you wonder if your going to die before you get the time to put your car together...

[The Pope]

Heres a little side track Q has any one tried to run a 6mm guide and valve stem in one of this head?

Our valve guides are short and our valve train ratios and so on suck. Your in the area of snapping the heads off the valves real fast with the 6mm stem. I won't get into the simply melting faster and falling off with boost either lol. Better head design is the way to go, not even the back cut (thin stem between head and guide) type high flow valves are a good idea with a turbo.

[bakes]

Our valve guides are short and our valve train ratios and so on suck. Your in the area of snapping the heads off the valves real fast with the 6mm stem. I won't get into the simply melting faster and falling off with boost either lol. Better head design is the way to go, not even the back cut (thin stem between head and guide) type high flow valves are a good idea with a turbo.


That's to bad there was a set of nascar tii valves for sale on Ebay

[RoadWarrior222]

I was pretty sure he did an 8v head as well as the 3.0 head. Last I knew it was up in the gallery somewhere, but it was a b!tch to search.

Well I can't find what I thought I was looking for. I guess what happened is that there was a 3.0 and 8v port shape comparison thread, with cutaways from someone else, and I thought Frank did all of them.

[Juggy]

Well I can't find what I thought I was looking for. I guess what happened is that there was a 3.0 and 8v port shape comparison thread, with cutaways from someone else, and I thought Frank did all of them.

all cut aways are in the knowledge center

[Shadow]

I have a brand new 655 and no body is going to cut it but me, and only in a friendly way lol

First off, glad you made it. It's about time everyone was able to get together and just air everything out!

You make some decent points, but keep in mind that alot of these things (while they work well) are replacements for the work involved in doing something Right.

eg. Do big plenum short runner intake manis work for high RPM? Sure they do, but that's not to say that a properly tuned longer runner mani won't.

This is the tricky part, understanding that there are a # of things that work well, the difference is usually in the amount of effort one needs to put into either of them!

Designing a longer runner intake, properly tuned for the RPM you intend to run is more than most can deal with. Too much math involved and too many ways it can go wrong IF you don't know what your doing.

Viola! In with the big plenum short runner mani, simple to build and while not properly tuned it does the job fairly well and ppl don't loose any sleep over it's shortcomings. (most prob don't even know what it's shortcoming are!)

So, going to be interesting to see how everything goes during this debate, cause usually the difficulty comes from lack of understanding in what I just described above!

There is more than 1 way to skin a cat! So someone come up with a old 655 casting and let's get SKINNING! (I have a feeling I'm going to have to dig one up myself!)

[BadAssPerformance]

There is more than 1 way to skin a cat! So someone come up with a old 655 casting and let's get SKINNING! (I have a feeling I'm going to have to dig one up myself!)

Someone has to have one thats junk condition? LMK, I got a fresh band saw blade here...

[Juggy]

have 1 here. not getting chopped....maybe if I Had the 2 or 3 more i should have suppose to have had :(

they got spread out locally. theres a few in the area but each of us only have 1. all after the mad "655" rush about 2 years ago....


altho I have recently developed a fondness for the 782 head, as I am currently porting one. they need LOTS of work, but there lots of material to play with to help change the shape of the port....

[omni_840]

Someone has to have one thats junk condition? LMK, I got a fresh band saw blade here...

There's JY down my way called the Car Farm that specializes in TM's. I remember the last time I was there he had a HUGE pile of old heads. The next time I go down I'll see if he has any.

Pardon my ignorance but does these heads have "655" on them like the 782's?

[Juggy]

There's JY down my way called the Car Farm that specializes in TM's. I remember the last time I was there he had a HUGE pile of old heads. The next time I go down I'll see if he has any.

Pardon my ignorance but does these heads have "655" on them like the 782's?

yep...

[omni_840]

yep...

Thanks

[thedon809]

There is one on ebay but I doubt someone would want to spend 200 dollars to cut one up. He sent me pictures of it.
http://cgi.ebay.com/ebaymotors/Chrysler-2-2-ltr-CYLINDER-HEAD-135-cc-81-85-NO-CORE-_W0QQcmdZViewItemQQhashZitem29ee79668fQQitemZ18009 4592655QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries

[thedon809]

Here is one.
http://i272.photobucket.com/albums/jj197/thedon809/omni/85%20glh/2703c2.jpg

[puppet]

I didn't read that one.... in the middle of stuff here with the GF at the moment, but having a dome is NOT a good thing.

On our dyno, talking with the operator/tuner, the larger the dome, the MORE advance you need to overcome the obstructive path that the flame travel is interfered with. Major downside....I remember reading Larry's article back then. I know you can't pull that off in a nitrous apllication (Mike/Zin could probably bare this out) .. and I suspect the same would hold true in FI. The article has some good points but taken with a grain of salt you have to understand 1) the focus was mainly w/(4) valve heads .. which have their own sets of flow issues .. 2) was it a little "sales pitch" to garner head/engine work back then? The guy was (still is?) in the developement business after all. It's expensive to get all the parts working together (pistons/chamber) cause they become basically "one off" pieces. Nice to talk about every year or so but not much else I'm afraid.

[puppet]

If I still had one I'd mold/plaster cast it. If we're just interested in port shape(s) that is.

[zin]

I remember reading Larry's article back then. I know you can't pull that off in a nitrous application (Mike/Zin could probably bare this out) .. and I suspect the same would hold true in FI.

Actually, nitrous will tolerate a very high compression ratio, it's just whether or not the fuel will! That's not to say this is ideal, in fact in testing done with Pat Musi many years ago, we determined that two identical BBCs, other than compression (one at 11:1, the other at 14:1), that while the high compression engine made about 50HP more than the lower compression engine with no nitrous. When 300HP of nitrous was added to both, the LOWER compression engine made 50HP MORE than the higher compression engine, even with the nitrous... The conclusion in that case was that the lower compression engine simply had more room to put "stuff". I would imagine, had we tested for it, we would have seen the dynamic compression on the low comp engine would show higher... The alternate is that lower energy stuff was replaced with higher energy stuff, or both...

Bottom line on piston domes (for me anyway) is that the top of the piston is the bottom of the combustion chamber, therefore it must be made to provide as uninterrupted a flame path as possible. And, if practical, encourage the hottest part of the chamber to burn first as it is the most unstable and therefore most easily detonated.

Further, although squish/quench are used interchangeably, they aren't exactly the same. Squish is used to induce turbulence on the compression stroke, the idea being to "blow" the mixture into the oncoming flame front, thereby speeding combustion... Quench is exploiting the fact that A/F mix won't burn right up to the wall of what is containing it, I can't recall off the top of my head right now, but I believe it's in the .020-.040" range. So, you pretty much have a layer of unburnt mix coating the inside of the combustion surfaces that won't burn (too cool). IF you time it right, and have the two surfaces come close enough to each other, the "end gas, the part that will most likely be detonating, will be "quenched" or snuffed out before it can happen.

One reason for using the terms interchangeably is that they are not mutually exclusive from each other... They can do both!

WOW, kinda got off on a tangent there, sorry for that!

Pistons... Due to the above book, I (almost) always recommend using as small a dome/dish as possible, if a dome is needed, it shouldn't be the rocky mountains, but more of a weathered sand dune, low and smooth, no sharp edges/corners. This is to allow smooth flame travel. In some cases it will be a decided advantage to run less compression and give up that potential HP for a higher quality burn that the lower dome would provide...

Mike

[GLHNSLHT2]

Here is one.
http://i272.photobucket.com/albums/jj197/thedon809/omni/85%20glh/2703c2.jpg

Notice how the caps are held on with studs, wish they would of kept doing that down the road. Easy to remedy but would of been nice to have stock.

[Aries_Turbo]

I remember reading Larry's article back then. I know you can't pull that off in a nitrous apllication (Mike/Zin could probably bare this out) .. and I suspect the same would hold true in FI. The article has some good points but taken with a grain of salt you have to understand 1) the focus was mainly w/(4) valve heads .. which have their own sets of flow issues .. 2) was it a little "sales pitch" to garner head/engine work back then? The guy was (still is?) in the developement business after all. It's expensive to get all the parts working together (pistons/chamber) cause they become basically "one off" pieces. Nice to talk about every year or so but not much else I'm afraid.


Normally when designing the chamber and piston configuration we never check the static compression ratio as long as the "combustion space" is acceptable, regardless of application (normally aspirated or force fed.) We have found that many of our engine's compression ratios were well over 23-1, and we also learned that allowing new customers to know those numbers was not always good for business. Monday mornings are still always fun when we get the call regarding how well the combinations ran, then we’ll let them to know part of the reason why. Regardless of the weekend performance, it still scares them to death.

simon, this is NOT for you.

you swoon at the very mention of an experimental process whether it is smart or not. stay away. stay very far away for your own protection. :)

[GLHNSLHT2]

Oh Come on, I wanna see simon run 30:1 CR

[Shadow]

Here is one.
http://i272.photobucket.com/albums/jj197/thedon809/omni/85%20glh/2703c2.jpg

Perfect, now get choppin! :nod:

[rib256]

I only have one, sorry, I can take pics though. How do I remove valves? LOL

[thedon809]

Perfect, now get choppin! :nod:That's the one that's for sale on ebay.

[cordes]

I only have one, sorry, I can take pics though. How do I remove valves? LOL

I find that this tool is pretty handy for it. I don't know if that's a good place to buy from or anything, but that's the tool I use.

http://djvmerchandise.com/pro1128396.html

[Juggy]

I only have one, sorry, I can take pics though. How do I remove valves? LOL

is the head off the car??? I use simon's method....hammer and socket!! seriously....it works awesome. I can have all 8 valves popped loose in under 2 minutes....just try to keep the keepers from flying with a rag or something

[Directconnection]

is the head off the car??? I use simon's method....hammer and socket!! seriously....it works awesome. I can have all 8 valves popped loose in under 2 minutes....just try to keep the keepers from flying with a rag or something

It's a good quick way to do it if you are tossing out the valves.... as it is also a good way to bend them at the heads.

[Shadow]

That's the one that's for sale on ebay.

Crap! Oh well......next!

[Shadow]

If I still had one I'd mold/plaster cast it. If we're just interested in port shape(s) that is.

After all this talk I think we need to settle on no less than a chopped cross section of the real deal! JMO

Seeing a real life cross section is going to speak volumes, specially on the exhaust side.

Like I said, if no one has a junker to chop up I'll come up with one, one way or another!

[Directconnection]

After all this talk I think we need to settle on no less than a chopped cross section of the real deal! JMO

Seeing a real life cross section is going to speak volumes, specially on the exhaust side.

Like I said, if no one has a junker to chop up I'll come up with one, one way or another!

I just got in from working at the shop ALL day and night. Lightening up a BB Chevy "modified" roundy-round block 12hrs and maybe I took 5lbs:D

Anywho... glad to see there's some good discussion in my thread, but unfortunately... I have no time to reply still. I have to get up in 6 hours...

This weekend I'll see if I can find a 655.... I had one many years ago.... don't know where it went, but I know a junkyard dawg that might have one in his stash to maybe volunteer and chop-up.

[turbovanman²]

I didn't read that one.... in the middle of stuff here with the GF at the moment, but having a dome is NOT a good thing.

On our dyno, talking with the operator/tuner, the larger the dome, the MORE advance you need to overcome the obstructive path that the flame travel is interfered with. Major downside....

Gotta read the article and it was a joke.


Conicals and the PTs weren't invented/1st used by Rob as far as I know.

Maybe so, but he basically got the word out. No one had heard of them until he kept plugging them.



I remember reading Larry's article back then. I know you can't pull that off in a nitrous apllication (Mike/Zin could probably bare this out) .. and I suspect the same would hold true in FI. The article has some good points but taken with a grain of salt you have to understand 1) the focus was mainly w/(4) valve heads .. which have their own sets of flow issues .. 2) was it a little "sales pitch" to garner head/engine work back then? The guy was (still is?) in the developement business after all. It's expensive to get all the parts working together (pistons/chamber) cause they become basically "one off" pieces. Nice to talk about every year or so but not much else I'm afraid.

I do have 16 valves. :eyebrows:


simon, this is NOT for you.

you swoon at the very mention of an experimental process whether it is smart or not. stay away. stay very far away for your own protection. :)

Its a joke, wow.


It's a good quick way to do it if you are tossing out the valves.... as it is also a good way to bend them at the heads.

I've done that method for 27 years, NEVER EVER bent a valve, I guess if your stupid enough to not put the head on some wood to give the valves some clearance then you could bend some.

[Shadow]

I just got in from working at the shop ALL day and night. Lightening up a BB Chevy "modified" roundy-round block 12hrs and maybe I took 5lbs:D

Anywho... glad to see there's some good discussion in my thread, but unfortunately... I have no time to reply still. I have to get up in 6 hours...

This weekend I'll see if I can find a 655.... I had one many years ago.... don't know where it went, but I know a junkyard dawg that might have one in his stash to maybe volunteer and chop-up.

Cool, I'll wait to see what you come up with.

[puppet]

I do have 16 valves. :eyebrows:
Cool ... now you just need to find $16,000 and you're all set. :P

[The Pope]

Cool, I'll wait to see what you come up with.

need to section along the ports for width too if you find one to show the bowls.:clap:

[Shadow]

need to section along the ports for width too if you find one to show the bowls.:clap:

For sure, I'll have 4 sets to work with, so I'll ( I would imagine Steve would do this also) be cutting them several ways to show everything I can.

[The Pope]

For sure, I'll have 4 sets to work with, so I'll ( I would imagine Steve would do this also) be cutting them several ways to show everything I can.

The Mopar drawing of the 655 intake shows peaks which is strange, the floor has waves.

A cut will also show how the bowls are a lot bigger on the 655 than the runner on the exhaust. My second test of one with just a gasket match gained over 15 CFM, Dick thought it was a waste of time and money because a gasket match isn't supposed to give you anything :clap: The intake is pretty simple but it will be intresting to see where people think the exhaust should be cut.

[zin]

The intake is pretty simple but it will be interesting to see where people think the exhaust should be cut.

I'll second that, but for just about all our heads...

Mike

[RoadWarrior222]

My second test of one with just a gasket match gained over 15 CFM, Dick thought it was a waste of time and money because a gasket match isn't supposed to give you anything :clap:

Well that's because it's fixing production variables rather than fixing what the engineers intended. One head might gain, another might not, depending how far off it was in the first place, and which side it was skewed to... If everything always came on the optimum side of spec, there would be no call for "blueprinting". Basically you got 15cfm that should have been there in the first place. If it was 15 cfm more than average for the head, it probably "unlocked" flow further up where core shift benefited it.

[boost geek]

The Mopar drawing of the 655 intake shows peaks which is strange, the floor has waves.

A cut will also show how the bowls are a lot bigger on the 655 than the runner on the exhaust. My second test of one with just a gasket match gained over 15 CFM, Dick thought it was a waste of time and money because a gasket match isn't supposed to give you anything :clap: The intake is pretty simple but it will be intresting to see where people think the exhaust should be cut.

Dick who? :confused:

[turbovanman²]

Dick who? :confused:

You, you dolt, :lol:

[Juggy]

You, you dolt, :lol:

theres more then 1 dick out there ya know


ps.....thats my married woman pick up line btw...:lol:

[turbovanman²]

theres more then 1 dick out there ya know


ps.....thats my married woman pick up line btw...:lol:

I know, just buggin, :p

Nice one, :nod:

[GLHNSLHT2]

rob is referring to Dick Flynn. The guy that does flow testing for us.

[Reaper1]

Nice to see The Old One (TOO) aka Larry Widmire brought up. He had forums on his sight years ago, but took them down due to him not having the time to be on them. In the fairly short amount of time I was active on those forums I learned a LOT! Not as much as I wanted to, but enough to get me thinking about things differently and where I got the notion that quality is better than quantity for air flow.

The idea of quench/squish I think should be investigated more. I've had an idea for pistons floating around in my head and in different drawings and sketches I've made for years. Instead of having a massive bowl for a dish, there is a "ramp" that encourages the mixture to go to the exhaust side of the chamber. I suppose you could consider it an asymmetrical dome, but it wouldn't be that high. The higher end of it would match the head and provide a squish/quench area. It's hard to describe with words, but I think that it could work pretty well considering the stock pistons don't really even attempt to do any of this.

I have a question for Warren. In looking at the pictures of your molds, is it an optical illusion that the intake ports are narrower at the enterance?

[turbovanman²]

Nice to see The Old One (TOO) aka Larry Widmire brought up. He had forums on his sight years ago, but took them down due to him not having the time to be on them. In the fairly short amount of time I was active on those forums I learned a LOT! Not as much as I wanted to, but enough to get me thinking about things differently and where I got the notion that quality is better than quantity for air flow.

The idea of quench/squish I think should be investigated more. I've had an idea for pistons floating around in my head and in different drawings and sketches I've made for years. Instead of having a massive bowl for a dish, there is a "ramp" that encourages the mixture to go to the exhaust side of the chamber. I suppose you could consider it an asymmetrical dome, but it wouldn't be that high. The higher end of it would match the head and provide a squish/quench area. It's hard to describe with words, but I think that it could work pretty well considering the stock pistons don't really even attempt to do any of this.

I have a question for Warren. In looking at the pictures of your molds, is it an optical illusion that the intake ports are narrower at the enterance?

That's what the link Brian provided shows then it was shot down by a few TM'ers as being a bad idea, :p

[Aries_Turbo]

well look at the article itself. larry said that he wouldnt tell his own customers how much CR they were running cause it sounds soooo crazy!

i wasnt saying its a bad idea. i was saying its a bad idea for YOU to try. :)

just stick with simple stuff simon. you need to max out a simple, proven combo before running face first to crazy land. :)

Brian

[GLHNSLHT2]

before running face first to crazy land. :)

But that's what simon likes to do.

[Warren Stramer]

I have a question for Warren. In looking at the pictures of your molds, is it an optical illusion that the intake ports are narrower at the enterance?
Yes, just the way the camera makes them look. The ports cross section gets progressively larger as you move upstream toward the bell entrance away from the valve seat, but when measuring C/S in the bowl and turn area you must subtract the profile area of valve stem and guide boss. That is why it is slightly larger there, to offset the bulk of the two.
the intake throat c/s is 1.905s/in, over the turn it is 1.92s/in, at the flange it is 1.970s/in, at the throttle plates it is 2.437s/in. Valve seat to velocity bell length (total intake tract lenght) is 13.87 in. the intake is tuned to the third harmonic.

[Aries_Turbo]

But that's what simon likes to do.

i know but then he wants advice on how to fix something you told him not to do in the first place and then when you tell him to change it, he wont do that either. :)

Brian

[Reaper1]

Yes, just the way the camera makes them look. The ports cross section gets progressively larger as you move upstream toward the bell entrance away from the valve seat, but when measuring C/S in the bowl and turn area you must subtract the area of valve stem and guide boss. That is why it is slightly larger there, to offset the bulk of the two.
the intake throat c/s is 1.905s/in, over the turn it is 1.92s/in, at the flange it is 1.970s/in, at the throttle plates it is 2.437s/in. Valve seat to velocity bell length (total intake tract lenght) is 13.87 in. the intake is tuned to the third harmonic.

Firstly I have to thank you for offering up that kind of in depth information! :clap: It's rare that somebody on your level will do that and I am VERY greatful for it!

I figured that the CS would be larger in certain areas in raw measurement due to taking into account the valve and guide, but that the actual VOLUME decreased progressively. You confirmed that pretty much. Are the top and bottom total lengths equal for the runners? REALLY stupid question, and I could dig out my books and do some math, but what rpm ranges were you tuning for? 3rd harmonic seems to be the norm due to packaging constraints, so that doesn't surprise me.

Thank you again for sharing! I can't say that enough! :amen:

[Reaper1]

That's what the link Brian provided shows then it was shot down by a few TM'ers as being a bad idea, :p

Yup...it's a TERRIBLE idea!! ;) Maybe one day I'll have the resources to actually try it to disprove or validate that claim. AFAIK nobody has tried it with one of our engines, so to me, what do they know!? Just like how TBC on the pistons increases detonation. All the people I know that use it have NO issues with it and in some cases can run even more timing than before.

Anyway...back to the original thread! :amen:

[turbovanman²]

well look at the article itself. larry said that he wouldnt tell his own customers how much CR they were running cause it sounds soooo crazy!

i wasnt saying its a bad idea. i was saying its a bad idea for YOU to try. :)

just stick with simple stuff simon. you need to max out a simple, proven combo before running face first to crazy land. :)

Brian

It was a joke BUT Steve and others said that IS a bad idea on any engine.


i know but then he wants advice on how to fix something you told him not to do in the first place and then when you tell him to change it, he wont do that either. :)

Brian

If I knew exactly what it was, I could fix it or maybe its ok? Just saying put a stock head and cams back on does nothing to figure what it is, now does it? Then no one learns anything, or is this TD.com?

[Shadow]

I have a question for Warren. In looking at the pictures of your molds, is it an optical illusion that the intake ports are narrower at the enterance?

I'm not trying to be a smart a$$ by asking you this so please don't take it that way.

Just curious, what shape would you have expected them to be?

[Warren Stramer]

Are the top and bottom total lengths equal for the runners? REALLY stupid question, and I could dig out my books and do some math, but what rpm ranges were you tuning for? 3rd harmonic seems to be the norm due to packaging constraints, so that doesn't surprise me.

Thank you again for sharing! I can't say that enough! :amen:

I measure the top total runner length, Measure the bottom total runner length, add them together and divide by two, will give centerline runner length.
It is tuned for peak power @ 7200 RPM. Remember, when you increase charge temp., and charge density the sound waves travel faster and can cover a longer distance in the same amount of time. So forced induction can be slightly longer than N/A.

[glhs875]

Yes, just the way the camera makes them look. The ports cross section gets progressively larger as you move upstream toward the bell entrance away from the valve seat, but when measuring C/S in the bowl and turn area you must subtract the area of valve stem and guide boss. That is why it is slightly larger there, to offset the bulk of the two.
the intake throat c/s is 1.905s/in, over the turn it is 1.92s/in, at the flange it is 1.970s/in, at the throttle plates it is 2.437s/in. Valve seat to velocity bell length (total intake tract lenght) is 13.87 in. the intake is tuned to the third harmonic.





That's what I'm talking about, a man that knows his setup!!!

[John B]

i know but then he wants advice on how to fix something you told him not to do in the first place and then when you tell him to change it, he wont do that either. :)

Brian Hmm. I wonder if he and I are related...

[RoadWarrior222]

Another reason to make sure it's roomy around the valve boss, even if the area is notionally adequate, would be to make sure you don't get a venturi effect there from CS narrowing and suck oil down the guides.

[The Pope]

I measure the top total runner length, Measure the bottom total runner length, add them together and divide by two, will give centerline runner length.
It is tuned for peak power @ 7200 RPM. Remember, when you increase charge temp., and charge density the sound waves travel faster and can cover a longer distance in the same amount of time. So forced induction can be slightly longer than N/A.

Where to start with this one. First at 135 CID, and a 3rd Helmholtz resonance
wave at 7,000 RPM with a average 2" diameter intake runner has a calculated desired runner length of over 21". To get the desired runner cross section down small enough for the Helmholtz resonance wave to work right you need the small 1 piece intake runners.

It isn't a sound wave. The wave makes sound though. This wave that people aim for in a normally aspirated engine is a fluid dynamic wave of air density. Timing this wave to where IN A NA ENGINE the high density impact of the wave hits the intake valve just before it opens makes more power.

SHADOW and GLHNSLHT2 have read my posts on SHADOW's intake and what I've described as what is going on in there so this for them is just a rewording. To start read these 2 URL posts and then I will explain the simple physics as to why this isn't happing on a turbo based forum. This post is not for Warren but for all to read.

http://en.wikipedia.org/wiki/Manifold_(automotive_engineering)

http://en.wikipedia.org/wiki/Helmholtz_resonance

Ok we now see that it is wave or air density, a sloshing of air back and forth in the intake runner in a NA engine. You can make the right diameter and length of runner to tune for different waves at different RPMs to use the wave to MAKE PRESSURE AT THE INTAKE VALVE. Rob has heard me say over and over how his intake stacks air at the valve which in turn creates more cylinder pressure and power. Broken record here. By making a runner funnel out wider to wards the plenum you effectively shorten your wave pulse. On NA engines they balance this by adding velocity stacks in the plenum. Then the wave isn't as disrupted by the air in the plenum. Like air blowing across the top of an empty bottle.

Now the way to impress people at this point is showing a lot of NA engine math and big words that they don't understand to give the impression of wisdom. I can do that but then people don't understand what is going on, so the simple physics description is always my choice. I don't sound very smart but people get a clear picture.

Take a box and fill it 1/3 deep with water. This box has a hole with a valve on one side of it. Take the box and push it back and forth gently. The water sloshes back and forth in the box. Stop moving the box and as each wave crashes into the walls of the box it loses strength. Now take the plug out of the hole on one side and slosh the water and watch what happens. Each wave into the wall of the box with the hole shoots the water through the hole like a jet. opening the hole right at the right time means a lot more water out of the hole huh? This is the simple example that can be tried at home of this air wave people are looking at in a NA engine.

So then what happens with boost? Why are people adding big plenum's, short runners funnel shaped? Lets play with our box of water a little more.

Time to add a divider plate in the box. Now push the divider plate half way across the box, pushing all the water to one half. Then slosh the water into a wave. The distance between waves is greatly reduced as your pushing the mass against the exit hole. The water is deeper with more pressure on it and water goes out the hole pretty fast now and the pulses are weak and small. At this point the water being pushed on will flow faster through the hole without disruption. With no pressure pushing the pulse was the only thing causing extra flow, with pressure the flow is there and is faster and more sustained without pulsing.

Lastly put a lid on the box and shove the water tight to one side and try to slosh the water. Nothing. Now open the hole and see what happens. Big spray. Now add a given pressure on the divider and open the hole but don't push on the divider. The water leaves at first strong and then dies off quickly.

Now every one here understands fluid dynamics and the effects of it, so now comes the explanation of this on an intake manifold.

The 1 piece has the right runner size in cross section and length for 6,000 RPM on a 135 CID engine for the wave to make more pressure on the valve and make more flow into the engine. The runners are small enough that with lower boost the wave still exists with boost, but the wave gets shorter as the mass of air from the plenum pushes against it in the runner. At this point it isn't working, and is causing a restriction. As the valve opens the wave isn't timed right, the plenum is too small to feed the runner and the runner is too long to maintain pressure on the intake valve. So like pushing on the divider to move water to one side of the box, then don't keep pushing when the plug is pulled. less volume moved.

Now lets take an intake where this isn't done, a turbo intake. With runners too short and the plenum large enough you are pushing against the valve tight as it is shut. A consistent push, not a wave. With a short enough runner and a big enough plenum that pressure against the valve doesn't drop when the valve opens. If the shape of the runner and the intake port funnels the air will speed up as it is pushed forcing more into a small intake valve hole. This gain in velocity from volume compression over takes exhaust back pressure from overlap (to an extent it is still a lot less). With the water box the bigger the hole the more water goes out the hole. To get the same water out a smaller hole requires a lot more pressure on the water. Small runners with pressure can't flow as much air as big runners, same fluid principle.

NA engines stick stacks in the plenum to put the end of the runner in the middle where all the pressure is. They add a larger intake runner and funnel it only at the intake port. That way the pulse is in the larger tube and the pulse hit the funnel intake and not the just bouncing off the valve. All of which works great when your creating a pulse to create intake valve air pressure. If the pressure exists already, why wouldn't you stick the plenum right on the end of the funnel into the port?

As for the thread, this isn't hijacking talking about the intakes. The 655 port allows you to stack more air pressure on the "hole" or valve with the right intake to feed it. All it asks for is some one to add a big valve and some love with a porting tool to use the volume :D

Now read about the Helmholtz resonance wave again. On a static runner this works to make pressure. If your running 30 PSI of boost on the runner why on earth would you want to design your intake to use it? Maybe you think the 30 PSI is going to slosh back and forth to make 50 PSI on the valve? No. The red neck description, stick 1 cow in a hall way and the cow will pace back and forth. If you open the door at the other end at the right time the cow quikly leaves the hall way, if he is at the other end it takes a while longer. Now run 50 cows into the same hall way and there is no movement, just wall to wall beef. Now open the doors at the other end and they all run out, and no cows are pacing back and forth as they leave, they're all moving the same direction even off a cliff. Sorry I'm used to explaining things to farmers ;)

[glhs875]

I'm not sold on the short runner big plenum intake being best. I would like to see a dyno and track time comparison on the same car/engine/turbo with the short runner/big plenum design, and then with an intake properly designed based on harmonics for peak power not peak torque. And maybe put a big plenum on the tuned intake, or better yet, have plenums with the same volume for both intakes. And the vehicle needs to have a standalone so each intake can be tuned for properly.

And start the dyno pull down low (around 2500rpm) if possible.


Without the comparison, I'm leaning towards a tuned intake, even on forced induction.


BTW, I have been using the same basic principals as Warren for my combos.

[Shadow]

Now the way to impress people at this point is showing a lot of NA engine math and big words that they don't understand to give the impression of wisdom. I can do that but then people don't understand what is going on, so the simple physics description is always my choice. I don't sound very smart but people get a clear picture.

Only a fool attempts to "give the impression of wisdom", and it becomes obvious to most if not All, that it is indeed a Fool that is speaking!

Someone who speaks from a depth of Knowlege combined with applied real life experience IS wisdom, impressions don't enter into it!

There is a limit that "truth" can be watered down before it becomes lost all together. So you first have to have a firm grasp on the truth, then answer ppl's Q's as well as you can according to what They are able to digest.

If you have found it more comfortable to speak in "lesser terms" in the hopes of reaching a larger audiece, that's fine, but don't be confusing that with ppl who are able to do both! ;)

[puppet]

The problem with your explanation Pope is that it doesn't take into account that an N/A engine also operates under pressure .. 14.7psi. You acknowledge that the wave(s) benefit that application ... so, what's a few more psi mean to the effect? Just because there is 50 .. or 100 psi involved doesn't mean the air charge turns into a solid .. like ice.

Another correction in your explanation concerns your description of the runner shape and the effect it has on the wave. ... unless I misunderstood your explanation to mean change of wave duration/timing. The wave is shortened as you say .. in "length" as the shape of the runners CSA changes. As it returns, the shape changes again. The "slug" has the same volume so to speak. So the runner C/S dictates it's length.

The big thing to recognize with wave tuning is that abrupt changes in shape effect the tuning duration. That's why there's very little when a short runner is employed. Good thing? ... bad thing? ... I think that depends. First you have to recognize that the wave effect exists under pressure. If so, why not take the advantage of the wave .. as long as it's tuned for the rpm you need it? ... details, aim small.

Plenum size is a big topic ... there is an ideal size for a particular combination. ... but it's also true that going too large doesn't gain a thing .. been tested at the track with other engines over the years. I'm still a believer in plenum including intake piping .. passed the TB... @WOT. Warrens set-up most definitely falls into this thinking. Unless we're going to take the position that he's making the power he is without a plenum? .. lol

ETA: I agree with Shadow ... you have to show how the wave effect isn't happening when pressure increases with a little more than a cow/hallway equation ... mmmmk?

[Shadow]

Where to start with this one. First at 135 CID, and a 3rd Helmholtz resonance
wave at 7,000 RPM with a average 2" diameter intake runner has a calculated desired runner length of over 21". To get the desired runner cross section down small enough for the Helmholtz resonance wave to work right you need the small 1 piece intake runners.

It isn't a sound wave. The wave makes sound though. This wave that people aim for in a normally aspirated engine is a fluid dynamic wave of air density. Timing this wave to where IN A NA ENGINE the high density impact of the wave hits the intake valve just before it opens makes more power.

SHADOW and GLHNSLHT2 have read my posts on SHADOW's intake and what I've described as what is going on in there so this for them is just a rewording. To start read these 2 URL posts and then I will explain the simple physics as to why this isn't happing on a turbo based forum. This post is not for Warren but for all to read.

http://en.wikipedia.org/wiki/Manifold_(automotive_engineering)

http://en.wikipedia.org/wiki/Helmholtz_resonance

Ok we now see that it is wave or air density, a sloshing of air back and forth in the intake runner in a NA engine. You can make the right diameter and length of runner to tune for different waves at different RPMs to use the wave to MAKE PRESSURE AT THE INTAKE VALVE. Rob has heard me say over and over how his intake stacks air at the valve which in turn creates more cylinder pressure and power. Broken record here. By making a runner funnel out wider to wards the plenum you effectively shorten your wave pulse. On NA engines they balance this by adding velocity stacks in the plenum. Then the wave isn't as disrupted by the air in the plenum. Like air blowing across the top of an empty bottle.

Now the way to impress people at this point is showing a lot of NA engine math and big words that they don't understand to give the impression of wisdom. I can do that but then people don't understand what is going on, so the simple physics description is always my choice. I don't sound very smart but people get a clear picture.

Take a box and fill it 1/3 deep with water. This box has a hole with a valve on one side of it. Take the box and push it back and forth gently. The water sloshes back and forth in the box. Stop moving the box and as each wave crashes into the walls of the box it loses strength. Now take the plug out of the hole on one side and slosh the water and watch what happens. Each wave into the wall of the box with the hole shoots the water through the hole like a jet. opening the hole right at the right time means a lot more water out of the hole huh? This is the simple example that can be tried at home of this air wave people are looking at in a NA engine.

So then what happens with boost? Why are people adding big plenum's, short runners funnel shaped? Lets play with our box of water a little more.

Time to add a divider plate in the box. Now push the divider plate half way across the box, pushing all the water to one half. Then slosh the water into a wave. The distance between waves is greatly reduced as your pushing the mass against the exit hole. The water is deeper with more pressure on it and water goes out the hole pretty fast now and the pulses are weak and small. At this point the water being pushed on will flow faster through the hole without disruption. With no pressure pushing the pulse was the only thing causing extra flow, with pressure the flow is there and is faster and more sustained without pulsing.

Lastly put a lid on the box and shove the water tight to one side and try to slosh the water. Nothing. Now open the hole and see what happens. Big spray. Now add a given pressure on the divider and open the hole but don't push on the divider. The water leaves at first strong and then dies off quickly.

Now every one here understands fluid dynamics and the effects of it, so now comes the explanation of this on an intake manifold.

The 1 piece has the right runner size in cross section and length for 6,000 RPM on a 135 CID engine for the wave to make more pressure on the valve and make more flow into the engine. The runners are small enough that with lower boost the wave still exists with boost, but the wave gets shorter as the mass of air from the plenum pushes against it in the runner. At this point it isn't working, and is causing a restriction. As the valve opens the wave isn't timed right, the plenum is too small to feed the runner and the runner is too long to maintain pressure on the intake valve. So like pushing on the divider to move water to one side of the box, then don't keep pushing when the plug is pulled. less volume moved.

Now lets take an intake where this isn't done, a turbo intake. With runners too short and the plenum large enough you are pushing against the valve tight as it is shut. A consistent push, not a wave. With a short enough runner and a big enough plenum that pressure against the valve doesn't drop when the valve opens. If the shape of the runner and the intake port funnels the air will speed up as it is pushed forcing more into a small intake valve hole. This gain in velocity from volume compression over takes exhaust back pressure from overlap (to an extent it is still a lot less). With the water box the bigger the hole the more water goes out the hole. To get the same water out a smaller hole requires a lot more pressure on the water. Small runners with pressure can't flow as much air as big runners, same fluid principle.

NA engines stick stacks in the plenum to put the end of the runner in the middle where all the pressure is. They add a larger intake runner and funnel it only at the intake port. That way the pulse is in the larger tube and the pulse hit the funnel intake and not the just bouncing off the valve. All of which works great when your creating a pulse to create intake valve air pressure. If the pressure exists already, why wouldn't you stick the plenum right on the end of the funnel into the port?

As for the thread, this isn't hijacking talking about the intakes. The 655 port allows you to stack more air pressure on the "hole" or valve with the right intake to feed it. All it asks for is some one to add a big valve and some love with a porting tool to use the volume :D

Now read about the Helmholtz resonance wave again. On a static runner this works to make pressure. If your running 30 PSI of boost on the runner why on earth would you want to design your intake to use it? Maybe you think the 30 PSI is going to slosh back and forth to make 50 PSI on the valve? No. The red neck description, stick 1 cow in a hall way and the cow will pace back and forth. If you open the door at the other end at the right time the cow quikly leaves the hall way, if he is at the other end it takes a while longer. Now run 50 cows into the same hall way and there is no movement, just wall to wall beef. Now open the doors at the other end and they all run out, and no cows are pacing back and forth as they leave, they're all moving the same direction even off a cliff. Sorry I'm used to explaining things to farmers ;)

This should be a very interesting thread IF everyone can "keep it together" and speek their own truth without getting flustered and giving up!

Since your "keeping it simple" I'll add this; from the very begining I believed that anything that will help an N/A mtr will help in a forced induction mtr. This, when the whole world believed that the two were completly seperate and could not be joined!

In the last 15 years all I've seen is that gap closing to the point where ppl are realizing that if you take a properly prepped deep breathing N/A mtr and add a little boost you make great power!

One of the great benifits of boost is it can mask a lot of things. If I've gone too large on my cross section, if my runners are too short, if my plenum is too large, all of these things that would/could really hurt an N/A engine that only has atmospheric preasure to rely on, can work on a boosted application.

This doesn't mean they're working at peek efficiency, although it may appear that way to the untrained eye! this is one of the reasons that builds are so confusing to some, because they see 10 different ppl build a boosted app 10 different ways and all 10 May have good results. It's simply because all 10 are gaining the benifit of the "masking" effect of boost, but none of them are completly optimized, otherwise 1 would stick out from the 10. ;)

The Charger was, and still remains to this day, a simple build. I did things that seemed the most simple to me, rather than spending a great deal of time trying to reach 100% efficiency, and it has worked well.

I have also followed Warrens build for many years now and am in complete agreement with Every change he has made according to every theory he has brought up based on complex mathamatical formulas that have existed for years.

I'll be the first to admit, I never did the math, it has always just been in my head, and it has served me well. Warren did the math, and it has served him BETTER!

Rob, I know your a fan of the Charger, but answer me this, do you really think it can hold a candle to Warrens build? Cause that's what your comparing here. Your basically arguing that the Charger is a more "proper" way to build a boosted mtr than Warrens, in which I whole heartedly have to dissagree.

A more simple build yes, more efficient, obviously Not! ;)

[puppet]

http://www.psiproformance.com/gallery/index.php?level=album&id=10

We ALL can do more with what we've got .. if that's what we want. (hope that i didn't stray off the campground too far posting that.)

[The Pope]

Now read about the Helmholtz resonance wave again. On a static runner this works to make pressure. If your running 30 PSI of boost on the runner why on earth would you want to design your intake to use it? Maybe you think the 30 PSI is going to slosh back and forth to make 50 PSI on the valve? No.

Actually yes with stacking. Actually higher if your feeding the valve right and you can sustain more boost at the valve at higher RPM. In a wave the pressure drops and is reflected towards the plenum dropping pressure at the valve. Stacking is like pouring water into a long tube where the pressure is highest at the bottom. At low RPM stacking will decompress into the plenum, at high RPM the stack benifits flow. This stacking your aiming for also benifits from port volume. I was falling asleep near the end of the post sorry. :lol:

[The Pope]

Rob, I know your a fan of the Charger, but answer me this, do you really think it can hold a candle to Warrens build? Cause that's what your comparing here. Your basically arguing that the Charger is a more "proper" way to build a boosted mtr than Warrens, in which I whole heartedly have to dissagree.

A more simple build yes, more efficient, obviously Not! ;)

Warrens engine has a higher VE than the charger. The car is a purpose built drag car not a street car like the SC. You would have to make a step up in flow to pass warren. A simple head, custom cam and different top end flowing parts. Mostly "technically" bolt ons.

Warren's setup is great, But like I've done with my GLHS I think he uses it as a science project to play with as much as he uses it as a race car. You don't have to go that far to go that fast. Add some manifold flow testing and your 4 bar computer to Gary's old reliant and you have a 9 second car.

Warren's setup has a good plenum and funneled runners, that don't produce this wave for NA engines but it does work at WOT for getting air into the engine and produce some good stacking.

My opinion of the Charger to run high 9's, would be some bolt ons and some weight reducing.

The head, a big valve ported 655 head like mine and Terry's
The exhaust manifold, a header or TU's cast manifold I KNOW flows big
Lone Wolf 655 size port custom intake like the give away engine. But with a 5" plenum instead and a larger TB like a 65-70mm.
The turbo needs to get bigger to reach 600 WHP. The HE351 is really close though so I'd keep it at first to see how far you could get.
Step up to a 2,000 CFM water to air intercooler.
coil over Koni's with 500 lb springs, get the car raked and close to the ground to keep wind out from under it at the big half of the track.
Solid engine mounts and Slowe's WONDERFUL metal suspension bushings, start twisting Brian's arm. Then add the right FWD alignment.
custom cam, FWD's F5 with .550 intake lift instead. My cheap valve train, expensive valves like Ti though. Ceramic coated head, chambers and exhaust ports.

A step in traction and flow at 40 PSI. The Charger with head light covers alone is incredible in the wind. Past 120, the whole second half of the track the Charger is much more capable of getting down force on the front tires and slicing through the wind than a Daytona.

As a big SC fan I'll donate flow benching and porting ;) My first TD bracket car in the late 80's was a SC. The first 9 second TD, the fastest land speed record holding TD at 238 MPH and could be the first street legal 9 second TD :clap: I am bias..... All with 8v's too BTW

Trany to hold it? Axles? Clutch? Kevlar high top shoe's? $3,000?

[The Pope]

http://www.psiproformance.com/gallery/index.php?level=album&id=10

We ALL can do more with what we've got .. if that's what we want. (hope that i didn't stray off the campground too far posting that.)

Big plenum mounted right to the head litterally. Big turbo with header. Head that flows. No intercooler pressure drop, E85? Drag car holding the engine not a street car. Typical with other hobbys.

[Shadow]

Warrens engine has a higher VE than the charger. The car is a purpose built drag car not a street car like the SC. You would have to make a step up in flow to pass warren. A simple head, custom cam and different top end flowing parts. Mostly "technically" bolt ons.

I'm glad You think it's that easy! lol


Warren's setup is great, But like I've done with my GLHS I think he uses it as a science project to play with as much as he uses it as a race car. You don't have to go that far to go that fast. Add some manifold flow testing and your 4 bar computer to Gary's old reliant and you have a 9 second car.

Gary's car was a featherweight, but again, I'm glad You think that 9's is as simple as making a statement! lol

My Q then, if it's so easy to run 9's why have only a couple ppl done it? (really not sure I should have asked! lol)



My opinion of the Charger to run high 9's, would be some bolt ons and some weight reducing.

The head, a big valve ported 655 head like mine and Terry's
The exhaust manifold, a header or TU's cast manifold I KNOW flows big
Lone Wolf 655 size port custom intake like the give away engine. But with a 5" plenum instead and a larger TB like a 65-70mm.
The turbo needs to get bigger to reach 600 WHP. The HE351 is really close though so I'd keep it at first to see how far you could get.
Step up to a 2,000 CFM water to air intercooler.
coil over Koni's with 500 lb springs, get the car raked and close to the ground to keep wind out from under it at the big half of the track.
Solid engine mounts and Slowe's WONDERFUL metal suspension bushings, start twisting Brian's arm. Then add the right FWD alignment.
custom cam, FWD's F5 with .550 intake lift instead. My cheap valve train, expensive valves like Ti though. Ceramic coated head, chambers and exhaust ports.

A step in traction and flow at 40 PSI. The Charger with head light covers alone is incredible in the wind. Past 120, the whole second half of the track the Charger is much more capable of getting down force on the front tires and slicing through the wind than a Daytona.

As a big SC fan I'll donate flow benching and porting ;) My first TD bracket car in the late 80's was a SC. The first 9 second TD, the fastest land speed record holding TD at 238 MPH and could be the first street legal 9 second TD :clap: I am bias..... All with 8v's too BTW

This is some funny $hit! (the timing of it) You'll know what I mean when I start my next thread on the Charger in a couple weeks! :eyebrows:


Trany to hold it? Axles? Clutch? Kevlar high top shoe's? $3,000?

Tranny, I'm thinking is going to be OK, no problems yet and it shifts better the faster I go!

Axels, we'll see, gonna keep running the stockers for now and see how many passes I get before shearing them.

Clutch? I guarantee the clutch I'm running right now will go 9's without issue!

Having said that, I also have something on the burner that will serve as back-up IF I were to run into trouble. ;)

[Shadow]

Big plenum mounted right to the head litterally. Big turbo with header. Head that flows. No intercooler pressure drop, E85? Drag car holding the engine not a street car. Typical with other hobbys.

So, What Rob, No love for ppl who have the shear will and determination to see just How Efficient they can design something?

Granted, the general population might not be able to appreciate, the time and effort, that someone like Warren puts into developing something as efficient as what he's achieved, but you?

Even IF I was able to put the Charger into the nines, as you described, Warrens mtr would still be more efficient, can you see (concede) that?

Anyways, this is starting to get a little off topic, unless you want to argue that it's the 655 head that your offering to port for me that's going to raise my VE higher than Warrens! :D

[turbovanman²]

Anyways, this is starting to get a little off topic, unless you want to argue that it's the 655 head that your offering to port for me that's going to raise my VE higher than Warrens! :D

Oh snap. That's all I have, lol.

[cordes]

I'm glad You think it's that easy! lol



Gary's car was a featherweight, but again, I'm glad You think that 9's is as simple as making a statement! lol

My Q then, if it's so easy to run 9's why have only a couple ppl done it? (really not sure I should have asked! lol)




This isn't the first time on here people have extolled the ease of running 10s or faster...

[Reaper1]

I'm not trying to be a smart a$$ by asking you this so please don't take it that way.

Just curious, what shape would you have expected them to be?

No..you're cool. I expected them to be more like how he later descirbed in the cutaway drawings. The optical illusion threw me off. DOH!


I measure the top total runner length, Measure the bottom total runner length, add them together and divide by two, will give centerline runner length.
It is tuned for peak power @ 7200 RPM. Remember, when you increase charge temp., and charge density the sound waves travel faster and can cover a longer distance in the same amount of time. So forced induction can be slightly longer than N/A.

Makes perfect sense, thanks! :thumb:


Where to start with this one. First at 135 CID, and a 3rd Helmholtz resonance
wave at 7,000 RPM with a average 2" diameter intake runner has a calculated desired runner length of over 21". To get the desired runner cross section down small enough for the Helmholtz resonance wave to work right you need the small 1 piece intake runners.

It isn't a sound wave. The wave makes sound though. This wave that people aim for in a normally aspirated engine is a fluid dynamic wave of air density. Timing this wave to where IN A NA ENGINE the high density impact of the wave hits the intake valve just before it opens makes more power.

blah blah blah...not reposting the entire thing.....


Wow...this is just....wrong! :nod: Pressure waves(which ARE sound), most certainly DO exist in conditions other than standard atmospheric, and not ony that, can carry MORE energy! You have to take into account WHERE you want to take advantage of that and go from there. If we could varry the runner length dynamically (like F1 cars) then this would be a non-issue. BUT, since boost is a moving target until we are at full spool and WOT, we can only tune for THAT condition, which Warren has done. The REASON most people don't want to try to tune an intake for a boosted application is due to the amount of vairable that can, and do screw up all the hard work! You can get close, but it is almost NEVER going to be 100% of what you get on paper, so it's easier to just overcompinsate and use brute force, like what you want to do. However, using a bit of finess can, and WILL yeild as good, if not better results! How about those of us that don't just drag race and are interested in transient response and boost recovery, or *GASP* part throttle engine performance? Making power isn't nearly as big of an issue as THESE problems are! Brute force in these instances doesn't work (or I should say it doens't work well).


Warren's setup has a good plenum and funneled runners, that don't produce this wave for NA engines but it does work at WOT for getting air into the engine and produce some good stacking.

Umm...they DO produce this wave! The amplitude has to increase as it travels up the runner, so therefor the energy over the area decreases, but the wave gets reflected back down the runner when it encounters the entrance mouth! The frequency (3rd harmonic here) is the same. Some energy is lost, but for the most part the total energy of the wave stays constant! Conservation of energy...you can't go against that rule unless you are claiming you are god!



Past 120, the whole second half of the track the Charger is much more capable of getting down force on the front tires and slicing through the wind than a Daytona.


WTF!? Where are you coming up with THIS logic!? Both cars share a VERY similar profile. They BOTH can be made to make a good amount of frontal downforce with the propper aero mods. In order to do this they BOTH require a deep lower air dam, at LEAST!



As a big SC fan I'll donate flow benching and porting ;) My first TD bracket car in the late 80's was a SC. The first 9 second TD, the fastest land speed record holding TD at 238 MPH and could be the first street legal 9 second TD :clap: I am bias..... All with 8v's too BTW

The 1st to hit 9's probably because it was chosen for wieght, NOT aero. Landspeed it was probably chosen because of its lower frontal area (downforce creates drag, so your argument becomes kinda pointless here).

[BadAssPerformance]

The head, a big valve ported 655 head like mine and Terry's

Since this is the "655 flow" thread, just curious if it was posted what these heads yer speaking of flow?

[Directconnection]

Wow...this is just....wrong! :nod:

(and then)

Umm...they DO produce this wave!

(and also this)

WTF!? Where are you coming up with THIS logic!?



You saved me mucho amounts of my time reading and replying.... and I thank you truly from the bottom of my heart :love:

Shall I just skip reading these last 10 posts then? :D

Rob, me thinks you have LOTS to learn from just asking people like Warren many questions. It's ok to admit that you'll learn something from another forum member. Just 4 months ago, I PM'd Warren so we could talk (ie: him teach me ;)) some of his math skillz behind the science of runner size and shape, and most importantly.... "choke" diameters, etc...

Heck, I even learned a few things over the past couple years from Simon!

Learning from others only makes YOU that much better...

[turbovanman²]

This isn't the first time on here people have extolled the ease of running 10s or faster...

WHAT? Its not easy? :confused: Muthertrucker, :lol:




Heck, I even learned a few things over the past couple years from Simon!

Learning from others only makes YOU that much better...

Pardon me? Are you feeling ok?

:faint: :eyebrows:

[Directconnection]

WHAT? Its not easy? :confused: Muthertrucker, :lol:



Pardon me? Are you feeling ok?

:faint: :eyebrows:

I was trying to be nice....:D

[dusterdude]

well... just spent the last 4-5 hours reading, trying to understand, and learn from this thread, even though there was alot of "technical" words that I have no clue what they mean, I have learned a ton! thank you everyone for this great info and great thread. and even this forum in general. It amazes me how much I have learned from the members since I have joined. :clap: :thumb: (sorry for the off topic post)

[The Pope]

So, What Rob, No love for ppl who have the shear will and determination to see just How Efficient they can design something?

Granted, the general population might not be able to appreciate, the time and effort, that someone like Warren puts into developing something as efficient as what he's achieved, but you?

Even IF I was able to put the Charger into the nines, as you described, Warrens mtr would still be more efficient, can you see (concede) that?

Anyways, this is starting to get a little off topic, unless you want to argue that it's the 655 head that your offering to port for me that's going to raise my VE higher than Warrens! :D

I have not bad mouthed Warrens engine, I did bad mouth one of his old engines that was pretty funny. But even that engine even though strange was done very clean. I have always said how nice Warrens work is, you are lacking a little self confidence I think. The SMP Charger wasn't even a tiny bit as clean as Warrens car when it ran 9's. My point isn't that Warrens car is lacking, the point is flash isn't always faster.

I believe that Warrens engine would be more efficient at the low end vs the engine I described. Mainly because that intake is a great street intake able to control vac down low. The LW intake on a 655 is a big volume setup, at high RPM where you make more HP. My intake for my GLHS is not hugely different than Warrens when it comes to flow or how it uses boost at WOT. With the muilti TB setup his engine can be pedeled a lot better. He can lift and restrict power evenly if he spins, won't be as much of an on off switch. Once floored they might as well not be there, which most I don't think understand.

Because of the setup it is possible to get a higher VE than Warrens engine with bigger flow not just from the head, but combined with a custom intake, cam and exhaust. A ton more? No not hugely different. But what I described and what Warren runs are still on a whole lower plain than the SMP engine. Still based off a basic factory port shape and location. A few $ with the local tig welder and I could raise the ports of a G head over a 1/2" and get to the 655 size port at the same time. Or keep going up and completely build ports into the valve cover area. I am able to do that level of porting. To be honast I think welding and raising ports on a G head is still easier than porting a 782.... Raising the ports and a custom intake lets you make a wider intake bolt spacing, or drop the spacing for a 4 bolt spacing. Then after raising the G head ports at least a 1/2 inch then weld up the chambers and build a good swirl chamber.. How far did you want to go anyway I guess I'm getting at?:D

I can also create a new flange location for 2" round ports (or larger) at the gasket instead of oval and give the flange and port angle to LW in autocad and really get the air moving. Keep in mind how many 16v race cars have you seen at the track that use the factory intake castings? Me and Warren both use factory castings ported, that limits flow. It takes a little time though. First off I would get the thing welded up. Then make my flange which I think I have already. Then cut to the shape I want. Then comes working the water jackets to keep it holding water and build up the sides of the runners. Then cut and port again, then weld up the runners, then cut and and sand. Then measure and sand out to size. You want to weld up and port your existing intake and go 655 or weld up the head you got and go past factory specs?

[Shadow]

I have not bad mouthed Warrens engine, I did bad mouth one of his old engines that was pretty funny. But even that engine even though strange was done very clean. I have always said how nice Warrens work is, you are lacking a little self confidence I think. The SMP Charger wasn't even a tiny bit as clean as Warrens car when it ran 9's. My point isn't that Warrens car is lacking, the point is flash isn't always faster.

See, you make a statement like this and you leave me thinking that you have No clue on just what Warren has done. I'm starting to think that Warrens work is so shiny, that it's Blinding you to what lies beyond. I would be willing to bet that Warrens VE is beyond what the 8v SMP was! (and not by a small margin :eyebrows:)


I believe that Warrens engine would be more efficient at the low end vs the engine I described. Mainly because that intake is a great street intake able to control vac down low. The LW intake on a 655 is a big volume setup, at high RPM where you make more HP. My intake for my GLHS is not hugely different than Warrens when it comes to flow or how it uses boost at WOT. With the muilti TB setup his engine can be pedeled a lot better. He can lift and restrict power evenly if he spins, won't be as much of an on off switch. Once floored they might as well not be there, which most I don't think understand.

Again, your missing the mark. Warrens intake will be better at ALL RPM levels.
It's tuned to make peak power above 7000rpm, this is what your describing as "more efficient at the low end"?


Because of the setup it is possible to get a higher VE than Warrens engine with bigger flow not just from the head, but combined with a custom intake, cam and exhaust. A ton more? No not hugely different. But what I described and what Warren runs are still on a whole lower plain than the SMP engine.

Really? You need to look further into Warrens build, see above post!

Rob, we need to get real here. Shake the cobwebs and take a good look at what's going on around you. If you think that the SMP 8v set-up held a candle to Warrens set-up, guess again!

Warrens current build, 50 trim and all in the SMP car that ran 9's weighing all of what, 1700lbs? would be in the 8's......wait for it......With a 50TRIM! What was Stephane running, a GT42r?

Anyway, were forgetting our manners here, and first things first.

Got any flow #'s on the ported 655's you did? We could at least use that as a starting point.

[puppet]

All the talk about raising the port runner ... anybody have a rough idea how much more the intake would flow with a mod like that? <---- If it made a big enough difference it could be worth the trouble.

Me being basically a lazy guy would think that fabricating (4) runner roofs and welding those inside the VC area would be easier. Then you could go beyond a 1/2" height. Do like Brian from Alabama suggested and fabricate a flange to bolt to the head .. fit the VC around that.
... but it has to be worth it. If that would allow flow closer to 300@28" .. woah. Getting additional mass into the charge that size would be pretty sweet.

One port could mocked up like this and flowed just to see anyway.

[RoadWarrior222]

Rough idea of range of gains could be got from flowing a piece of plumbing pipe with a 90* bend on the end, then flowing it with a 45* bend on the end.

[Warren Stramer]

All the talk about raising the port runner ... anybody have a rough idea how much more the intake would flow with a mod like that? <---- If it made a big enough difference it could be worth the trouble.

Me being basically a lazy guy would think that fabricating (4) runner roofs and welding those inside the VC area would be easier. Then you could go beyond a 1/2" height. Do like Brian from Alabama suggested and fabricate a flange to bolt to the head .. fit the VC around that.
... but it has to be worth it. If that would allow flow closer to 300@28" .. woah. Getting additional mass into the charge that size would be pretty sweet.

One port could mocked up like this and flowed just to see anyway.

Would there be any gains if you could build a 8V head with sewer pipe size ports and not be able to fit larger valves?
What is limiting flow now, Port size or valve area?

[Directconnection]

Rough idea of range of gains could be got from flowing a piece of plumbing pipe with a 90* bend on the end, then flowing it with a 45* bend on the end.

I have the formula for you to find out exactly. An OLD and rare article I found in my mass of 4,000 magazines from CJ Batten in a Chevy magazine, nonetheless.

Remind me and I'll post it for you if I forget tonight/tomorrow:D

[turbovanman²]

Would there be any gains if you could build a 8V head with sewer pipe size ports and not be able to fit larger valves?
What is limiting flow now, Port size or valve area?

Good point.

[puppet]

Would there be any gains if you could build a 8V head with sewer pipe size ports and not be able to fit larger valves?
What is limiting flow now, Port size or valve area?Bigger ports don't neccessarily mean better flow. I know that you know that. Raising the port roof would require filling the floor to keep an effiecent MCSA. One that is kind to a wider rpm range. Most likely what you have arrived at already .. just repositioned.

I think what's limiting flow right now is the port approach to the valve. Question was/is ... does changing the angle improve flow rates ... yep, but by how much? ... and what's the best angle for the desired port CSA?(smaller ports supposed to like shallower angles vs larger ports .. actually seen some paperspublished on this topic.) Granted .. mod'ing a head in this manner is a stupid amount of work. ... unless a way to section out the ports was devised along with a CNC'ed billet section to be laminated back in place (2000* epoxy). Raising intake and exhaust ports.