Ok, I took Jeller out with me to watch me guages while I did some light baseline pulls. my car is technically untuned but i do have prelim setting for my application from RRE. Now keep in mind that i want to run 15lbs and have a manual boost controller. We put the softest spring avalible to us(low boost spring from FORGED manual boost controller). On 3rd and 4th gear WOT pulls the boost sweeps to 15-16 lbs and as rpms go up the boost creeps up to or almost at 20lbs. and i have to shut down cause im scared/positive it will break 20lbs.
On my build i did port the waste side of the o2 housing for this problem that i was told about. apparentlly with the apexi n1 3in there has been cases of this and i was advised to do so.
Tom, per our conversation, looks to be the wastegate flapper needs to be upgraded to a 34mm vs. the stock 28mm.
Also looks like some have made the wastegate outlet and the turbine outlet UN-divided and say this works also…? Can anyone confirm the better method here? I would assume the upgraded flapper would be the better of the two options.
What kind of fuel system do you have, Tom? Grounding out the dividor between the wastegate and the exhaust is a great way to keep boost creep down or eliminate it altogether. If you have at least 550’s, you can run 20lbs on that motor with that turbo no problem.
Probably not. I had the same problem even after installing a new o2 housing.
Mine was an easy fix though, I just got tuned for 20psi. My 50trim has a 34mm flapper and ZI ported/smoothed that out and I get no boost creep even at 8 psi lol.
