HO Intake Manifold vs. Stock - Dyno Results

[Spilner521]

There's a guy over on j-body.org who finally dyno'd the stock manifold vs. the HO manifold.

Here's the link:
http://www.j-body.org/forums/read.php?f=2&i=400177&t=400177

Current mods:
1) Intake and Exhaust cams are 200 @ 375
2) MD Ld9 lightened crank pulley
3) 2.5" magnaflow cat and 2.5" custom catback w/ factory flowing style muffler
4) TTR upper and lower mounts
5) Ebay AEM style intake
NO header, NO ported head, NO hstqc


Dyno results:

Stock 2.4 intake manifold (red line) - 141whp/144wtq

2.3 HO intake manifold (blue line) - 134whp/134wtq
http://img161.imageshack.us/img161/8195/hovsstockmd4.jpg
The manifold has a 2.4 flange on it so port matching isn't even a question:

http://img148.imageshack.us/img148/5225/24flangeho1op9.jpg
http://img162.imageshack.us/img162/8821/24flangeho2gv7.jpg

[jackal2000]

so what i am taking away from this is the hybrid concept is not all its cracked up to be?

[DOHC_tuner]

yeah i thought so the HO weights more, but it still does looks better. But now we know its not worth the time and effort. But they do say it'll be better for turbo applications.

[pawzbear]

haha i always thought that hybrid was silly so here we go!! =-P

[DOHC_tuner]

Not the WHOLE concept, just the heavy HO intake manifold

[pawzbear]

yeh i could see how it would benefit a boosted setup more...

[Vinalero]

That was interresting. I agree with them when they say the HO was made for a higher rev and quite a few more hp engine.

On a N/A the engine probably lose hp sucking the air in the manifold design. Also, this guy doesn't have headers, maybe the flow from the intake is too big for the exhaust and the ECU runs it a bit leaner to compensate. Or maybe I'm a complete mecanical dumbass :p

[AGT]

Dang HOs mess everything up. Nothing but drama :lol:

[DOHC_tuner]

That was interresting. I agree with them when they say the HO was made for a higher rev and quite a few more hp engine.

On a N/A the engine probably lose hp sucking the air in the manifold design. Also, this guy doesn't have headers, maybe the flow from the intake is too big for the exhaust and the ECU runs it a bit leaner to compensate. Or maybe I'm a complete mecanical dumbass :p

:lol: :lol: :lol:

[spyhunter]

well if you're a stock bolt on guy, the ho manifold is not for you.

If you're doing headwork, have some nice cams, header, exhaust, and intend to tune the setup, you'll end up benefitting from it.

[spyhunter]

this is a great example but less drastic of...

hey guys I have a full 100% race header on my car that's great.................. on my bone stock motor that doesn't know what to do with it!

[Oldsman]

interesting.

[Spilner521]

well if you're a stock bolt on guy, the ho manifold is not for you.

If you're doing headwork, have some nice cams, header, exhaust, and intend to tune the setup, you'll end up benefitting from it.
I totally agree with you Spy. But you and I both know, maybe not everyone, but many people doing the HO manifold swap are the people that only have an intake and a cat-back on a stock tune.

Oldsman - what other top end work do you have done, including your exhaust?

[spyhunter]

I totally agree with you Spy. But you and I both know, maybe not everyone, but many people doing the HO manifold swap are the people that only have an intake and a cat-back on a stock tune.


In which case they should case they should be looking at other things to step up before this needs to step up.

All that lil .org post showed me was that, if you want to take advantage of an HO manifold you better have some supporting modifications that necessitate the flow of the HO. Some good cams, and headwork that will "suck" in all the good air. Anything beyond intake header exhaust, people need to start thinking things through, and incorporate PCM tuning. If they want it done, "right".

[Oldsman]

Oldsman - what other top end work do you have done, including your exhaust?

secret cams, polish and ported head, ho intake, 62mm tb, header, 2.5 all the way back with high flow cat and other little bolt on crap.

I noticed when i did the swap orginally i lost power on the low to mid range. but after doing the head and cams and header i runs better. that 62mm tb is still killing the low end but so is the added weight.

Based off ASS mine is running right with 2.2 eco 5-spd and a 3400 with bolt ons. so not bad with the added weight.

This whole dyno thing just so you can't just throw crap together and have it work. You have to know what the hell your doing.

[Spilner521]

secret cams, polish and ported head, ho intake, 62mm tb, header, 2.5 all the way back with high flow cat and other little bolt on crap.

I noticed when i did the swap orginally i lost power on the low to mid range. but after doing the head and cams and header i runs better. that 62mm tb is still killing the low end but so is the added weight.

Based off ASS mine is running right with 2.2 eco 5-spd and a 3400 with bolt ons. so not bad with the added weight.

This whole dyno thing just so you can't just throw crap together and have it work. You have to know what the hell your doing.
On your setup, with all the extra top end work and full exhaust, the HO manifold probably does help since the supporting mods can take advantage of the extra flow. And I agree with you and Spy...engine mods have to be thought out and everything has to compliment each other, instead of just throwing parts on that look good because everyone else did.