I was told that this can be done. Gutting the stock GSR IM......so that it will flow better in the high end (kind of like a B16 od ITR)....has anyone done this before?

 

how do you gut a intake manifold? I've heard of people gutting a cat converter before, but i dont know about a IM.

 

do you mean removing the butterflies? cause thats the only thing actually in the intake manifold that i know of.

 

yeah...that is what i meant. But is it possible??

 

Taking out the butterflies will essentially flow more air above 6000 rpms, but do you realize how much? The reason why I put it that way is because you will lose a considerable amount of power (very noticeable) when driving around on the street.. There's more to this, hopefully someone will respond, but if you want to experience what this feels like BEFORE 'gutting' your mani, disconnect the IAB plug.. This is what controls those 'butterflies'..

EDIT:
By the way, these 'butterflies' on the 'ludes and gsrs are used for this: There are 4 ports in the GSR manifold, 2 primaries on top and 2 secondaries on the bottom.. The secondaries are closed by these butterflies.. At 6000 rpms, the IAB solenoid tells the butterflies to open.. If u disconnect the IAB solenoid plug (very easy), you will experience what it's like to drive around town with your mani gutted, and sucking too much air into a motor that doesn't need it, resulting in considerably less torque and power between 2-5k rpms..

This concept is used by full-race guys that need every ounce of power they can get from their limited budget.. For a street car, I think it's dumb.. If u want a free'er-flowing street intake, either port the gsr and leave the butterflies, get a skunk2 mani, or get a ported skunk2 mani


[Modified by HKxBlur, 3:15 PM 4/30/2002]

 

i disagree, infact, quite a bit. Not sure though on the GSR, my manifold has the butterflies stuck open, and the car runs very well still. its still very easy to drive around town, and still faster then any GSR i've encoutered.

 

Well, I do alot of road crouses so high end power seems to me more important to me. But i am not sure if you can even take out the secondary butterfly......just that i heard it from someone and wanted to verify if it can be done.

 

Yes, it can be done! I have a Gs-R mani with the butterflies removed. I haven't had a chance to install it because i'm having it powder coated so, i'm not sure if it gives any noticeable difference.

 

Why respond to a 9 yr old post?

 

Maybe to add some information that others can look at. I've also had mines removed for a few years, no problems actually. H22a1, I remove the plate and studs and used shorter bolts. My experience is only drving it every day, I'm sure it probably lost some power in low-end - but nothing I've noticed actually. I did it mainly to clean things up, and try it out. I'm running a p28 so I don't have anything to control the butterflies anyway. Just adding my .02 like the other guy Have a nice day, its sunny out!!

PS. I know I'm talking about a h22, but I've also done it on 2 GSR engines I've had before, didnt notice any real losses - wound up going with a skunk2 single-stage manifold anyways, felt better top end, but mid range felt the same to me . Hope that helps someone reading this! -l8r