How much hp is a slightly ported 1pc intake good for

[83scamp]

I made 215hp ON THE DYNO TO THE WHEELS at 20 psi of boost with almost all stock parts except 3" swingvalve and downpipe, obviously not using all of the available power the turbo is capable of making but keeping it at a safe level for the tune I had and turbo longevity.

Figuring in drivetrain losses, you were pretty darn close to that 240 mark at the crank.

Point of declining returns, differences in dyno's any number of factors.

You are going to make more power going from 10 psi to 20 than going from 20 to 30. Intercooler, compressor and turbine restrictions are coming into play.

Gas was always 94 octane Sunoco.

I would agree. From the multiple chassis dyno information I have read, results can vary widely depending on the dyno. The only real data you can gather is multiple runs on the same dyno to see if thing improve.

I'm far from a turbo expert, but from some of the info & articles I have read, Gary is 100% correct. The closer you get to the edge of a compressor map for a given turbo, the less efficient it becomes. A turbo needs to be selected based on where you plan on running it. In the middle of the map is where you want to be. You want whatever turbo you use to be in it's " sweet spot" when you are trying to make max power. That 25-28 psi range is on the ragged edge of what a stock Garrett can do, and it's losing a lot of efficiency doing it...

Plus, going back to the original reason for this thread, it you're using a one piece, at 28 psi, you're probably pretty much stuffing all the air it can handle through it. That leads to inefficiencies of its own...

[Vigo]

im not really sure how you got my quotes all mixed up

Are you sure you're not misunderstanding (or ignoring) MY statements?

You said:

gary said that he made 254 on all stock parts at "all" of it boost, so how much was that 28psi?

Gary said:

30 pounds on a stock 89 TII

You said:

ok, so how did YOU "calculate" your hp # on your 2.5?

I said:

The fact that i made basically the same power as you AT 3700 RPM (i.e. something is wrong with the setup) at 16 psi ON THE DYNO

Keywords being on the dyno. I was on a dyno.

You said:

so you say that a 2.2 should make 240 hp at 20 psi, but gary made 254 at all of it boost

I wrote a whole paragraph about this!

I would not be surprised if you took a '30psi' TII dyno and only dropped 10 peak hp running it at 22. Gary basically already proved that with his daytona vs csx runs.

You said:

and of coarse the 2.5 is going to make more power almost everywhere in its efficient rpm range, its a "bigger" displacement engine, especially when you just said hp is a calculated number and we all know that the 2.5 makes way more tq so the hp figures will also be more at those rpms, so what happens is the hp (and tq) will fall off at higher rpm with stock parts because it wont flow well enough up there.

I said:

A 2.5 doesn't have any PEAK horsepower advantage over a 2.2 with the same top end parts.

2.5 will make more HP at lower rpm, but it takes the same amount of airflow to make the same amount of power so the peak hp#s will be very similar, just at different rpms.

[OmniLuvr]

Figuring in drivetrain losses, you were pretty darn close to that 240 mark at the crank.

I believe that, im just trying to figure out if we are focusing on chp numbers or to the wheels, or calculated numbers from track times? because quite frankly, I don't know of basically anyone who has ran there Chrysler 8v on an engine dyno? although that would be frickin awesome for back to back testing on our engines...

[Vigo]

Some of that is my fault. My original 240hp was meant as CHP. I'll go back and edit that for clarity.

[GLHS60]

Short rod to stroke ratio engines like a 2.2 and even more so a 2.5 respond well to a later intake valve closing point. Did the peak torque number stay the same even though it was being shifted to the right?

Found it!!

Thanks
Randy

[2.216VTurbo]

So Prestige, inadvertently you created one of the most active threads on TM.com, if I could be so bold as to summarize, I think my early thoughts that you would be hampered by your 1 piece are unfounded, should be plenty of margin to run your combination at IFO. Run lotsa boost, kick a$$ Heck, even I learned a thing or two in this thread

[Vigo]

Randy, do you know what all the changes were between those two dyno pulls on that sheet?

[wheming]

Randy, do you know what all the changes were between those two dyno pulls on that sheet?

Wow, would like to know that too. That is a significant bump in hp between the two. If that was just from some cam retard, and no other change?

[mopar-tech]

I believe that, im just trying to figure out if we are focusing on chp numbers or to the wheels, or calculated numbers from track times? because quite frankly, I don't know of basically anyone who has ran there Chrysler 8v on an engine dyno? although that would be frickin awesome for back to back testing on our engines...

5DIGITS.

Moving the engine from engine dyno to chassis dyno = 18% loss with a 568.

See? 40 year old info still has value.

;-)

[Keito]

So Prestige, inadvertently you created one of the most active threads on TM.com, if I could be so bold as to summarize, I think my early thoughts that you would be hampered by your 1 piece are unfounded, should be plenty of margin to run your combination at IFO. Run lotsa boost, kick a$$ Heck, even I learned a thing or two in this thread

Actually I was going to post a day before you questioning the 1 piece but I thought I'd see where the thread was headed first.
I started a 1 piece thread years ago and one of the Washington state guys told me he'd rather run a log intake.
I questioned it because I was told I could run a 1 piece on a GLHT without cutting the drip tray.

[Shadow]

The Reliant exceed 440 hp to the wheels with a stock camshaft and it had more in it.

Agreed, the Charger made 480WHP on the dyno with stock cam and stock ported exhaust mani and I Knew at that point I could exceed 500WHP IF I wanted to on the stock cam, just to say it could be done.

But the Clear indication at that point was that a Better profile cam would make Significantly More power on Significantly Less boost........

And thank you shadow for posting your #'s with associated parts, seams like the "combo" of a more efficent turbo AND intercooler (plus free'er flowing exhaust) will let the engine make better hp at lower boost psi numbers with a smoothed out not "modded" 1 piece intake, but there is still more to be desired with the 1 piece intake.

so basically you can make plenty of power with a 1 piece if the other parts of the turbo system are satisfactory, but at a higher boost level depending on what your bottom end and tune can handle...

I personally always thought the 1 piece is very restrictive but at least with factual dyno results you can see that it is still "effective" but if you have the opportunity to swap intakes its not a bad idea...

This has always been the Dance, and it has confused many. I still think the easiest way to "see it" is through thermodynamics;

Most are thinking that there is some significant Efficiency to begin with and that we can only effect that efficiency by Small %'ges with various changes to the system.

The Truth is that an average internal combustion mtr is what? 15-25% efficient? (Thermodynamically speaking)

Once you Understand this, and Also understand Why, then you can make changes in the right direction that will have a Significant impact on the over-all efficiency of the system.

I've said it many times before, you can get lost in the thinking that efficiency is simply "more power on less boost". That is the slippery slope!

As Gary and others have shown/ stated, you really don't Know what efficiency there is, till you have gotten as much as possible out of the package you have

[shadow88]

5DIGITS.

Moving the engine from engine dyno to chassis dyno = 18% loss with a 568.

See? 40 year old info still has value.

;-)

Any info on Automatic power loss ?

[83scamp]

I started a 1 piece thread years ago and one of the Washington state guys told me he'd rather run a log intake.

Wow!!! Not sure where he got his info. From everything I've read the log is terrible. Even Chrysler knew it because they changed the injector pulse on #4(IIRC) because of the crappy flow...

I'm with Alan though. This thread has been a wealth of information!!!

[glhs875]

Found it!!

Thanks
Randy

Nice gain! A detailed explanation of the combo and how many degrees the cam was retarded would be awesome!

[Reaper1]

Actually I was going to post a day before you questioning the 1 piece but I thought I'd see where the thread was headed first.
I started a 1 piece thread years ago and one of the Washington state guys told me he'd rather run a log intake.
I questioned it because I was told I could run a 1 piece on a GLHT without cutting the drip tray.

Was that "Pope" who said that? You know...the guy that did something like 180mph in a stock GLHS (or so he claimed at one point)? LOL

[OmniLuvr]

Are you sure you're not misunderstanding (or ignoring) MY statements?

sorry bout that, post count in this thread got a little crazy and I was bouncing back and fourth trying to read through...

BUT... what intercooler where you running?

[GLHS60]

Randy, do you know what all the changes were between those two dyno pulls on that sheet?

"Wow, would like to know that too. That is a significant bump in hp between the two. If that was just from some cam retard, and no other change?"

"Nice gain! A detailed explanation of the combo and how many degrees the cam was retarded would be awesome!"

Obviously I forgot how to multi quote!!

He has a 1986 GLHT, forged piston 2.5, stock exhaust manifold with a Holset and heavily modified 1 piece, stock cam.

New engine so he was taking it easy RPM wise trying to keep it together, Dyno was over 200 miles from home.

I wasn't there but encouraged him to try retarding the cam once it was warmed up and A/F checked.

He assembled it with an adjustable cam gear at zero and backed up the cam a total of 6 deg.on the dyno, several pulls.

Cam was not degreed just assembled at zero. Ran great and pulled strong at zero, top end vastly improved each time he retarded it. Never tried advancing as it kept improving each rime he retarded it.

Not sure of the boost as he was taking readings before and after the intercooler and had a great (12 psi) variance!!

He figured maybe restrictive intercooler, I figure inaccurate gauges, not sure.

The cam timing was all that changed and made a huge difference as noted.

The car pulls very, very strong, he has a self imposed 6,000 RPM redline but it feels like it would pull at least 7,000 +

His extensively reworked 1 piece probably helps take advantage of the late cam timing.

Bottom end power hasn't suffered, 1st gear is almost useless (A 555) so he starts in 2nd when performing "acceleration" tests.

Never thought a 2.5 could rev so freely!!

Thanks
Randy

[wheming]

He must have some head work done?
I would like to see my combo on the dyno at some point. Maybe after some more tuning. Would be good to remember testing some cam retard, although i am starting off with mine degreed already.

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[2.216VTurbo]

His extensively reworked 1 piece probably helps take advantage of the late cam timing


Any pics of this reworked one piece Randy? I only have a couple of 2 piece manifolds left but I may never run out of the 1 piece's so if they work well and keep me out of scrutiny with the Cali Smog police I may be modding a few more...

[tryingbe]

I would like to see my combo on the dyno at some point. Maybe after some more tuning.

Find a Dyno shop that can read A/F and boost, and get a Dyno operator that knows what he's doing then get the basics right on your car/van (big enough fuel pump, injectors, basic a/f right, plugs gap right, easily adjustable boost controller, on-the-fly tunable calibration, etc) and tune it on the dyno. I'm glad I did.

He has a 1986 GLHT, forged piston 2.5, stock exhaust manifold with a Holset and heavily modified 1 piece, stock cam.



Thanks
Randy

It's funny how close his 2.5L match my 2.2L torque curve, up to about 6100rpm. My cam timing is advanced by 1 degree, perhaps I should dyno it again when the weather is cooler.



Blue 20psi dyno tuned, Red 15psi street tuned.