Thread: whats up
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Old 12-04-2007   #67
niterydr
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Join Date: Oct 2003
Location: Elkhart Texas
Drives: 2015 Ram Quad Cab Hemi, 1999 FRC Corvette, 93 Stealth Turbo
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Re: wats up

Quote:
Originally Posted by JET View Post
Boost creep is caused by the wastegate not flowing enough. You will likely have to get the turbo ported and the O2 housing. 205 isn't too bad for low boost, get the issues figured out, then turn it up! Also, if you turn the boost up to 15 psi, it will still creep to 19, it won't make it creep higher.
Yes on needing wastegate work, incorrect on the ability to crank it up down low, here is why:

Most of the time it is an overall exhaust flow issue. The wastegate is getting choaked/can't bypass enough, so most of the time you have to start the boost lower than you'd like so you don't end up overshooting. Severe boost creep (like this car has) nearly makes the damm car nearly supercharged, increase in rpm is an increase of boost, and it says linear* when you are running into a flow restriction.


* It is not directly linear as you run out of compressor efficiency, but with his car it was shooting for 20+psi easily, something I didn't want to do on a smic w/o timing control on a 16g.

Welcome to the forums, glad you figured it out!
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