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3rdGen3.0
01-31-2006, 01:37 AM
Well, I've got a spare 3.0L that will be going under the knife soon...

From what I've read, the 3.0L SOHC have horrible heads... has anyone had any success in porting and polishing them?

I'm just planning on gasket matching and getting rid of casting flaws... anywhere else to pay special attention to?

I'll also be ccing the heads...

Frank
01-31-2006, 08:14 AM
I have a set of heads that are being finished right now and being sold to the person that can pay my cost in it. They are Steve Menagon heads. But I can tell you this... it will take alot of caution, small changes, and lots of flow benching. These cost me over $1k, and they have oversized exhaust valves, ported intake and exhaust, and reshaped intake ports. They were bad before... the exhaust would only flow 103cfm from .3 to .5" of lift. They now flow 143cfm without the bigger valve at .5". The intake is somewhere around 170cfm without the port being reshaped. Stock was 15x cfm?


Frank

Frank
01-31-2006, 08:16 AM
Here are my cross sections that I gave Steve to work off of....
http://www.squirrelpf.com/gallery2/v/Frank/Frank-Cars/Frank-Cars-V6HeadCrossSectioned/


Frank

Ondonti
02-03-2006, 12:15 AM
Not to be a poop head to frank, but kmperformance.com will port heads for a decent price and their flow #'s are good when you are using stock cams. I think Ed Kelly who does the porting has some ideas on getting even better #'s. I have already spent enough money getting their help so Im porting my own heads.

Here is my personal version of ported heads
http://memimage.cardomain.net/member_images/9/web/249000-249999/249196_31_full.jpg
http://memimage.cardomain.net/member_images/9/web/249000-249999/249196_32_full.jpg

Probably not a great Idea on an n/a engine deshroud the valves as much as I did unless you go to 10:1 compression or shave the head a good bit. My work will lower the compression ratio a good bit.

BTW I have nearly finished all the combustion chambers. I had already finished most of the port work but I decided I needed to go back into the turn in the exhaust port and try to fix things more.

I have spent at least 40 hours porting the heads. I can see why it is soooooooo expensive. It is probably the most mentally stressful car work I have ever done. I used knowledge from some of the books I own to help steer my work. There is a lot more literature on non crossflow head porting which really doesnt help a crossflow head like ours because you arent working with swirl into the chamber, but tumble instead.

Im going with oversize valves so I would have taken out less material if I was going stock valves.

Frank
02-03-2006, 08:15 AM
His numbers are wrong. I believe he used the wrong bore size on the flow bench. Its the only thing we can account for. His stock flow numbers are significantly different what we achieved on the 3.0L heads. Sorry, but I trust my guys more because of their huge credentials... both Steve Menagon and the guy who does all the flow benching. Steve's work on the 2.2L and the 2.5L has been astonishing and has proven some very trustworthy work and results.

But we wont turn this into a pissing contest. I just talked to Steve, and since he only had 1-2 test ports done, we worked out a small deal, and we wont be finishing these heads. The time it takes, as Brent is finding out quickly, and the flow produced is just not worth the hassle for him and for myself trying to finish the heads and then turn around and sell them.


Frank

Ondonti
02-04-2006, 03:05 PM
are the flow #'s in the charts the flow #'s you guys came up with stock?

I have a lot of faith in what im doing, and i would like accurate flow #'s so i can have them in case i can afford a custom cam.

Frank
02-05-2006, 12:25 AM
Here are the numbers you should be going with...

All numbers flowed by Steve Menagon and the right most column is from Bowl & Short Turn work including some deshrouding. Big valve not yet done before I cancelled the work.

Lift Stock Head Steve M
0.10 44.50 44.50
0.20 103.95 103.95
0.30 147.01 151.47
0.40 161.86 172.26
0.50 183.00 194.00

Lift Stock Head Steve M
0.10 31.50 31.50
0.20 78.75 75.40
0.30 97.65 110.25
0.40 103.95 133.87
0.50 103.95 148.05

MOPAR2YA
02-07-2006, 03:04 AM
Flow benches are like dynos they will all very to a degree and weather humidity etc effect readings. Core shift in a head can very one to another as well. Lastly keep in mind flow is only part of the equation, velocity will greatly effect low and mid range power/driveability. Dont get to caught up in flow #s alone.

Frank
02-07-2006, 06:28 AM
I agree Wallace, however the flow numbers they list on the exahust very by close to 30cfm for stock flow!!! The intakes only very by no more then 10 cfm. I think the guy they used just plain did a half arsed job.


Frank

Ondonti
02-08-2006, 08:26 PM
I did notice a lot of core shift in the ports.

Ondonti
02-12-2006, 08:05 PM
Well I finished the Combustion chambers. I havent cc'd them yet but Im going to leave that till the end. Im doing my last port work now, fixing the floor and roof of the exhaust ports. The floor of the "turn" is finished on 2 ports and it looks and feels very good. When I finish the floors then I will work on the roofs. Im using a goofy way of measuring. I have a bunch of grinding discs that I was using and I ground them all down to different sizes, so I can gradually go through and make sure everything is the same in each port, and I can go step by step removing a little material at a time.

Probably the most stressful thing of all is being consistent in your work.

Ondonti
02-21-2006, 05:15 AM
I finished porting my heads. I also just finished cc'ing the heads.
The measurements are 50.5ml 50.5 50.5 50.8 51 51.1 Just a little grinding and things will be great. Im actually already almost at +-.2ml which is a good goal to shoot for when ccing heads. Im amazed that I removed 4-5 cc's and I got so close. I think my hand ported chambers are more even then the stock chambers which is pretty funny.

Now I can take them to the machine shop!!!!!!!! Now I just need my cams. :evil: :evil: :evil: :evil: :D :D :evil: :evil: :evil:

Wink
02-21-2006, 09:11 AM
Sweet!!!!!!!!!!!!!!!

Ondonti
02-21-2006, 10:13 PM
I took a crapload of pics before I went to the machine shop. Maybe ill post some.

EDIT: http://www.cardomain.com/ride/249196/1 Here are the pics of my final port work.

c2xejk
03-26-2006, 01:10 PM
Well, I've got a spare 3.0L that will be going under the knife soon...

From what I've read, the 3.0L SOHC have horrible heads... has anyone had any success in porting and polishing them?

I'm just planning on gasket matching and getting rid of casting flaws... anywhere else to pay special attention to?


From my testing, standard porting and polishing of the intake does little to help and in some cases can hurt performance, if you are using stock sized valves... The exhaust side can be helped some by standard porting.

In both cases, what to do and what not to do is not always obvious...

I am in the middle of trying something different. The flow bench results look promising, but I am not going say much more until I get the heads on my van and get some dyno numbers...

My goal (with stock valves) is less big flow numbers and more improved fundimentals... That said, flow gains seemed to be coming along too... Better than I have had before...

A couple words of advice

-don't gasket match. Port matching is Ok. Manifold matching is also good (ie use prussian blue.)
-In terms of dry flow, unshrouding makes little improvement with stock valves. It may help with wet flow, but I don't have a wet flow bench to test that.

Ed Kelly
www.kmperformance.com

Frank
03-27-2006, 10:12 AM
-In terms of dry flow, unshrouding makes little improvement with stock valves. It may help with wet flow, but I don't have a wet flow bench to test that.


This maybe true, but unshrouding plays a big part in cylinder mixing and overall combustion & volumetric efficency. When you start adding those dynamics, this is a huge player.


Frank

c2xejk
03-27-2006, 09:50 PM
This maybe true, but unshrouding plays a big part in cylinder mixing and overall combustion & volumetric efficency. When you start adding those dynamics, this is a huge player.


Frank

Ok, lets take this one step at a time.

Mixing, do you have wet bench or other kind of data to prove this? Any other kind of data? ABA Dyno runs? This is an area where legendary porters such as Joe Mondello have found that having edges in the combustion chamber help with mixing... As long as they do not interfere with wet flow.


Combustion, any dyno or other data? One downside to massive deshrouding on a head like the 3L is reduction of the quench area and thus increasing the combustion chamber. Over do it and the burn is going to happen over a longer time (area) and thus could reduce hp or atleast. This problem has been noted on a lot of modern cylinder heads like the 3L.


Volumetric efficiency, how is this different from flow? Are you trying to talk about the area under the flow curve? Again, any data to back this up?


Much of these would take a wet flow bench (possibly with a special setup with piston in the bore) or dyno runs to prove. I would love to see info on this since I don't have a wet bench to test with.

I could see once velocity is pumped up, wet flow could become an issue. But that is pure speculation. Has this been noted during the testing/porting of your 3L head? Or are you just speculating on how the 3L head will react?

Frank
03-28-2006, 10:24 PM
I am mearly providing a counter point. See people blindly following things said on the internet a little too strongly and maybe taken a bit too literal. See you take someone and make a statement, they take it as truth. I should have stated something like typically and not pointed it directly to something like the 3L.

Will it work on the 3L? Takes testing, but in general as long as the combustion chamber dynamics are followed you can find that deshrouding valves comes in handing. Effective on the 3L? I dont know and I wont be finding out. I have scrapped my 3L project. The heads are too much of a pita and I want to try some other overal system efficencies with header and intake ideas, and I need a good head to do so. This is why I have chose to do some 2.4L work.

As for the general concept of deshrouding valves and such I am mearly going off of work like ENDYN and even some general discussion with well versed head porters. Now with all things being equal, deshouding hurts power because you have now changed the dynamics of the cylinder head. For people that go with some drastic over bores of engines, you will find that all of people deshround their valves drastically but also require some very drastric combustion chamber work. More then most would attempt for this application. Typically you would weld in the combustion chamber, lower the valve seats for better port flow, and even do some heafty piston work to assist with the mixing since now you have a shallow combustion chamber. I am not that familar with all the dynamics but I am just rambling on about some of the effects.

In terms of volumetric efficency, it is rather interesting. See the expanding volume in the chamber creates a vacuum. Now where I am going with this does not mean that these results are seen. It depends on alot of variables, but depending on the deshrouding, you will find that you can achieve a higher port velocity. This allows for a higher volumetric efficency in some cases. So yes it is flow, but is also effected by residual gasses from the exhaust side, etc. It is a measure of fresh usable air. It is effected by alot. It is actual air over theoretical air. Flow data while effects it is not directly proportional, it is a factor.

I have been doing some studying of Haywood's book which is 600+ pages of theoretical comparisons to actual real world application. One of the things that interests me the most is actually comparing flow data to what you expect volumetric efficency to be. Fun stuff if you ask me.

Some notes on the 3L deshouding would probably really screwup the mixing unless you get a good piston design. This is partly because of how deep the combustion chamber is. If I was continuing my project, I would go with the .90+ overbore deshround extensively, however I would run into the same problem I came across before. You have horrible mixing again. So that means weld in the combustion chambers, but the angle between the valves if lowered would interfere. The heads are pitas. I have found so much screwed up about them. So anyway, that is my opinion in my small experience.

The 2.4L heads have been known to achieve 320cfm by INDY. That is impressive and all the parts for building race 2.4L is so cheaper and fabrication time is way less. With all the traveling I do for work, this was pretty appealing.

Frank

c2xejk
03-29-2006, 12:29 AM
Port velocity is chiefly controlled by port cross-sectional area. Increase the port volume too much and the velocity drops...

It is true that valve shrouding can limit flow and thus reduce velocity. But I don't think that is the case (w/stock valves) on the 3L head, I would have seen flow gains from deshrouding if that were the case.

Since the original question was about a mild porting, I am trying to keep my answer confined to that. Oversized valves will almost definitely require some deshrouding...

You mentioned amount of fresh air into the chamber. Reversion is one of the key mechanisms for excess exhaust gas in the chamber. This is caused by poor low lift flow and/or a propensity for the intake and exhaust to flow better in the reverse direction upto the overlap valve lifts...

I must admit, I have not yet check reverse flow on my port design... It is still on the todo list... However I am not overly concerned right now because I have picked up low lift flow (I am measuring from 0.05" up to 0.4" in 0.05" increaments.) So they both breath well in the correct direction.

I think there is room to improve the 3L head without going overly radical. So I am putting my money were my mouth is and porting up a set heads. As you are aware, designing and testing the port layout take time...

The key problem as you mentioned is velocity related...


PS. I have Haywoods book at work. I have been involved with implementing some of his equations for diesel engines on dSpace Autobox. The goal is combustion statistics and cylinder by cylinder closed loop control... Next up is stuff it all into a dedicated controller... :)

Frank
03-29-2006, 09:44 AM
Yeh I hear you. Its a giant balancing act that is just plain messy and I think these heads are just plain pitas. For the power requirements and some of the efficency stuff I want to play with, they just werent for me... mainly the exhaust side.

How do your heads flow at 40"? This is great for determinening how your heads will be effective at conditions similar to boosting a motor. Just curious. ;)

That Haywood book is awesome. I have been working some of the combustion dynamics to form a desktop dyno. It is in its infant stages, however has some real potential. Right now it wont be looking at the combustion chamber, but will be currently focusing on fuel & ingition related combustion burn times and comparing that to mechanical advantages in the motor. I hope to get back on play with that in the next few months. It is currently written in excel with these massive tables, when really I want nice formulas, so I am going to rewrite it into PHP or java applet so I can use it on the website easily. Check out my current website for the new and improved web based version of my turbo calculator.


Frank

Ondonti
03-30-2006, 12:11 AM
Ahhhhh, Im a bad person

.090+ overbore, huge deshrouding.

We (my machine shop) put in an order for +2 intake and +1 exhaust stainless valves yesterday. Dont see a point going bigger on the exhaust because the stock valve is so much bigger then even a "ported" port.


Anyways, if anyone wants a piece of the action we will find out if they will cut a deal for multiple sets after they fax back an estimate.

im guessing between 240-300 bucks right now. (~20 per valve)

Wink
03-30-2006, 01:01 PM
That's not bad. Are they recommending any springs? Or will the stockers work fine?

Ondonti
04-01-2006, 04:30 AM
Im not sure yet. Im gonna wait till I have all the parts. I think im just worried if they will bind.

Frank
04-02-2006, 10:08 AM
I doubt binding would be an issue unless you changed the amount of lift with that cam you bought. Even then I guess it is all relative. If they do, maybe a conical type spring since they change diameter would have less of a chance to bind. Just a random thought is all.


Frank

Ondonti
04-02-2006, 06:09 PM
cams are 278 adv 216 deg @ .050" lift. .450" lift

so thats why im worried about binding.

Frank
04-02-2006, 06:17 PM
i figured that was your reason. ;)

Ondonti
04-03-2006, 01:30 AM
Im really not sure how to check besides assemble the heads and see if the springs bind up..........

I dont want to have to install springs twice though.

c2xejk
04-03-2006, 07:31 AM
Your machine shop should be able to check this during the time they pressure check the springs. Ask them to check how much lift the springs can handle before they bind...

Frank
04-03-2006, 10:07 AM
You can do it in much of a similar manner.... just more difficult. They are used to those things. Since you have a cam, tell them that you need springs that can handle that lift. They should be able to find them.


Frank

Ondonti
04-03-2006, 06:30 PM
I just did that today lol. He said bring him 2 springs and 2 retainers and we will see if they will take .450" valve lift.


BTW, my valves are going to cost $12 per valves. +2 intake +1 exhaust. My machinist seems worried about what the quality might be. Si valves.