Okay, so from 1000 to 5000 rpm's or so, my boost peaks at 7-8psi, but from 5000 to redline, the boost climbs to 10-11psi and stays there (until I shift, of course). I'm on a small Mitsu 16g in a '95 GSX with a cold-air intake, big-ass intercooler and no aftermarket engine management system whatsoever...

 

16gs are known to creep. when you turn the boost up it wont do that anymore though, when i had mine at stock boost, it would start at 9 and creep to 15 by redline!

 

ya thats boost creep for ya. a friend of mine seen it alot on his evo16g

 

Welcome to the world of boost creep where at times it can be deadly.

 

So whats the problem? 12psi is ok.....Or is it that you want it to spool faster?

If you really want to run that low of boost and your worried about the creep, try making the vacuum lines as short as possible and/or port the wastegate.

 

i think the only solution is porting the o2, but if you want 12psi all the time, turn the boost to 12psi that way its there from start to finish 12psi all the way thru. right now you are set at like 9, turn it up until it hits 12psi at the start.

 

Yea my evo3 16g does it too, even with thewastegate ported. it would hold 10 psi fine until about 5000 rpm them creep up to 15-16 ish and then the horrible feeling of fuel cut. It sucks but hopefully with some bigger injectors and a tune i can run more boost and eliminate the problem.

 

Agh! The dreaded fuel cut! LoL I had a crazy boost leak a little while ago that led to me hitting fuel cut at 3000 rpm's! ...feels like you're hitting a brick wall...

Anyway, my car's at the Brothers today, and they'll be fixing pretty much anything they can find on it. I'm getting my AFC from S&R Performance, and the Brothers are going to street-tune it, and then S&R is going to beat that tune on their AWD dyno.

Is there any way to kill the creep?

 

a better actuator might help the boost creep too

 

I had boost creep up to 26 psi on my talon but it wasnt a problem since my car was setup for it.I recommend switching to a external wastegate setup.