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What manifold are you using now? It must out do the RBC by some length. I'm interested to see what your dyno results are.
 

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For those wondering, Stefan @ ASP ported my RRC to flow 390cfm, his words.
 

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so 2500 rpms is now 2% of the powerband? Looks to me like you see exactly where you'll land after each shift, so i'd argue it's the most important part of the powerband.
Yeah who cares if midrange is sacrificed if the purpose of the car is to race if you want to be above 6500rpm all the time anyway.
 

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For those wondering, Stefan @ ASP ported my RRC to flow 390cfm, his words.
Yes, but what does that mean hp wise? Did you happen to get before and after dyno results?

Static flow as a straight shot down each runner with the plenum cut open on a flow bench is NOT representative of flow in the real world with a closed plenum and side mount tb.
 

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Yes, but what does that mean hp wise? Did you happen to get before and after dyno results?

Static flow as a straight shot down each runner with the plenum cut open on a flow bench is NOT representative of flow in the real world with a closed plenum and side mount tb.
No, I am just sharing the numbers I was given in correspondence with the thread.
 

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What manifold are you using now? It must out do the RBC by some length. I'm interested to see what your dyno results are.
Before the ported head I made 279hp with ported xcessive 54mm port, I got an AFI threw trade and installed it, retuned and made 283hp..

With adding e85 and retune I made 286hp... I decided to send head to 4 piston because goal was 300hp NA..

I've since added ported head and make over 300 now on both pump 93, and e85
 

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When I sent Stefan his 9.0 manifold he put it on his flowbench and told me it flowed 450 CFM, which I have some doubts about but that's what he told me.
The point is: Intake manifold flow has nothing to do with the HP an engine makes UNLESS the intake manifold flows LESS than the head.
Its the harmonics designed into the manifold that control the shape of the torque curve and the HP output.
 

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Before the ported head I made 279hp with ported xcessive 54mm port, I got an AFI threw trade and installed it, retuned and made 283hp..
Not sure i would hang my hat on a 4 hp difference. That could certainly be within the error of measurement of the dyno.

1civic said:
With adding e85 and retune I made 286hp...
I'm surprised e85 gave such a small hp increase. Makes me wonder about the atmospheric conditions between the two runs.

Head porting is definitely a good bang for the buck with these motors:up:
 

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The point is: Intake manifold flow has nothing to do with the HP an engine makes UNLESS the intake manifold flows LESS than the head.
Its the harmonics designed into the manifold that control the shape of the torque curve and the HP output.
Absolutelly correct! I can remember Larry (Endyn) talored me a 2 custom IMs for B series (3rd harmonics). The 2 was the same except for runner lenght (1" dirrerence only) and plenum volume. 20hp all over the TQ curve in VTEC and different peak location.
 

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When I sent Stefan his 9.0 manifold he put it on his flowbench and told me it flowed 450 CFM, which I have some doubts about but that's what he told me.
The point is: Intake manifold flow has nothing to do with the HP an engine makes UNLESS the intake manifold flows LESS than the head.
Its the harmonics designed into the manifold that control the shape of the torque curve and the HP output.
so you want the manifold to flow the same or more than the head essentially?
 

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BlackNDecker,
This isn't one of those POS Dynojet things. Rigorously controlled scientific experiments require the use of extremely sensitive and reliable measuring instruments, and a Dynojet simply doesn't qualify. We get 100% repeatable results down to .5 HP on the Dynapack. Year after year after year the same engine with the same setup and calibration always makes the same HP. I always do a minimum of 3 runs on each new setup to be certain of its validity.
So when I say a 4 HP loss there's no margin of dyno error involved.
That was a back to back to back test, and the 4 ponies reappeared when the 78mm T/B was put back on.
 

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Kick to ze liver,
The intake manifold should always flow a LOT more air than the head can. You always want to have as much port velocity as possible, and the design of the intake manifold, if done correctly, can increase the port velocity by a substantial amount no matter what RPM the engine's running at.
Knowledge of fluid dynamics is highly critical in intake manifold design. Who do you think was the first guy to put a velocity stack on a Honda intake pipe? Yep, that was me, and knowing about fluid dynamics is why I did it to begin with.
 

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Kick to ze liver,
The intake manifold should always flow a LOT more air than the head can. You always want to have as much port velocity as possible, and the design of the intake manifold, if done correctly, can increase the port velocity by a substantial amount no matter what RPM the engine's running at.
Knowledge of fluid dynamics is highly critical in intake manifold design. Who do you think was the first guy to put a velocity stack on a Honda intake pipe? Yep, that was me, and knowing about fluid dynamics is why I did it to begin with.
Right now I am running an ASP ported RRC manifold on a 2.0L RSX k20z1 w/ a custom 4" CAI....would you recommend building a velocity stack for the intake? I have a feeling the filter might be bottle necking the setup.
 

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Right now I am running an ASP ported RRC manifold on a 2.0L RSX k20z1 w/ a custom 4" CAI....would you recommend building a velocity stack for the intake? I have a feeling the filter might be bottle necking the setup.
How much power do you have with that setup? And as far as the 4" intake goes, is it tapered?

Stock head?
 

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BlackNDecker,
This isn't one of those POS Dynojet things. Rigorously controlled scientific experiments require the use of extremely sensitive and reliable measuring instruments, and a Dynojet simply doesn't qualify. We get 100% repeatable results down to .5 HP on the Dynapack. Year after year after year the same engine with the same setup and calibration always makes the same HP. I always do a minimum of 3 runs on each new setup to be certain of its validity.
So when I say a 4 HP loss there's no margin of dyno error involved.
That was a back to back to back test, and the 4 ponies reappeared when the 78mm T/B was put back on.
Joe, thanks for the clarification:up:...but I was referring to 1civic. Not sure if he was using dynojet or dynapack for testing.
 

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How much power do you have with that setup? And as far as the 4" intake goes, is it tapered?

Stock head?
It's not tapered, it made 215whp on Xenocron's mainline dyno. Add approximately 9% for dynojet numbers....~240-250whp. Stock head w/ DC 2.2s + Supertech valvetrain.
 
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