Intake manifold mods

[axis]

I know that i've personally been skeptical of IM porting and still am to a point, but I recently got the chance to test out a modded, NOT PORTED IM. Big thanks goes out to Rhino and GPI for the IM and the time it took to run the tests. The results weren't overwhelming but good nonetheless. Not so much in the peak numbers but the gains throughout the entire powerband. Not sure if porting alone would be as good or porting in addition to modding would be better. All I can attest to is the results from this test. For those that might be thinking, free advertisement for free/discounted parts, I paid full price for this intake.


Car is a bolt-on 2010 L99. Mods: Kooks 1 3/4 headers with HFC's, Halltech Yellowjacket CAI, and GPI dyno tuned. Absolutely nothing else, engine wise, is done to the car. Both the baseline and IM graph were done on the same day, within hours of each other. Had to let the engine cool to swap intakes. It was strapped to the rollers the entire time. The car was then brought back up to temps and retested MULTIPLE times. I bet we did 6-8 pulls with the modded intake so we could get good repeatable results. The tune was not touched in any way after the swap. The AFR's weren't affected at all, making this a no-tune necessary mod. This is the first bolt-on car that Rhino (GPI) has put his intake on. He has put this intake on cam cars that showed at least double the peak gains but the common thing is the consistent gains throughout the whole graph. He's also running one on his 10.45sec NA beast. This is a NA IM only as the way it's currently modded, it wouldn't hold up to boost. The run we chose was the best repeatable run.

The IM mod. unfortunately I didn't get a pic of the inside but it's a round bar that's secured inside and above the runners to smooth out the airflow into them. Hopefully Rhino has a picture to better illustrate it. Black RTV was used to seal up bar securing holes that had to be drilled in the IM, hence the reason it won't work for boosted applications. Those spots are hidden so you can't tell it's been modded at all, when it's on the car.

Thin line is the baseline, thick line modded IM.

As you can see, the numbers don't blow you away but they're consistent gains from 3600-redline. Roughtly 4/4 and they were repeated multiple times. This is truly a mod that will grow with you and give better gains to everything you add.

[Denis]

so this is something that GPI does as opposed to porting? or can this be done in addition?

[Rhino79]

Can be done in addition to. And I will give real credit where it is due to Rick Crawford as he really is the daddy of this mod.

I saw it over a year ago and tried it on mine and a buddies car. It works.

[62nalide]

Glad to see this on paper!

[Camarojt]

Rhino did this mod on my Bolt On Only car last summer and I think the results are well worth it! I Didn't get a before and after dyno so nice write up showing again why GPI helps you GO FAST!
My car isn't too shabby!

[Camarojt]

Here is a pic of the inside to show the difference!

[axis]

Mine still has the center posts, lol.

[Rhino79]

Removing the center posts don't do much. The magic is in the radius bars. Max effort, sure, gut it out.

[axis]

You know i'm good, just commenting.

[Camarojt]

Mine still has center posts too. This is a Rick Crawford picture. I have pics of mine but the lighting isn't very good so I just posted this. But you get the idea.

[Denis]

ugh i wanna do this...need to find a spare manifold.

[raw_shark]

How much does this cost to have done?

[grocerygetter]

axis I want to hear about how this thing drives now. Gotta be noticeably different after tune and intake.

[Pro Stock John]

My RCR: