aron2063

ok, im going to ask this question for the 100th time because its driving me crazy, i have a B16A2(99 civic Si) and i have a saab T3 and intercooler, and Vortech 12:1 Fmu and check valve, ok.. i have the boost at about 7PSI and it runs at that all the way up to about 6000 RPM, and then the boost lowers and lowers and by the time i get to red line(8000 RPM) the boost has fell to about 2-3 PSI, people have told me that its probobly my intercooler, so i took it off and its still doing the same thing, now i was maybe thinking that its the charge pipes because they are really small in diameter, they are probably 1 1/2 inches inside, someone also said it may be my exhaust because its stock except for a straight through muffler, do anyone have an idea what it could be, any one with the same car and the same problem mayber please help!!!!!!!!!!!!!!!!!

BlinD

Is the turbo reaching such high rpm that its stopped producing as much boost?

tranceminister

That would be my guess too. Maybe the turbo just isn't big enough to produce the kind of boost you want at that rpm. What size turbo is it, and what engine do you have?

turbocivic17m

aron2063

so i need a bigger turbo i would agree with you but hears a questin for you, if my friends t25 which is smaller than my t3 boost his eclipse gst 16PSi all the way up to 7000 Rpm then why cant my t3 boost my car 7PSI to 8000, my turbo is at 4PSI at 7000 RPM, so i dont think the turbo is the problem?

BigJ

But you are forgetting the one thing. The c/r on the stock gst/gsx is around 8.5:1 and yours is 10.2:1

You are also making more power with 7-8 psi than he is with 1 bar. Just because his engine is larger than yours doesn't mean jack. My del sol smokes my buddy's gsx, I'm running a 14b at stock wastegate 8psi and he has a t25 at 1 bar with a butterfly valve.

chingro

this not suppose to happen, i myself installed a a/r 60 T3 on a B16A, and it ran 8 psi up to about 6000-6300, as he revs higher you can feel the turbo has reach it's full efficiency at about 6300, but the boost DOES NOT DROP...

take you car to a turbo specialist, somthing is not hooked up right.

i would think it is your wastegate, it is opening to wide on the topend, and it is killing your boost on the topend.

later

d16forlife

I agree wiyh CHINGRO.The turbo should hold it's max set boost even if it reaches it's max R.P.M.You would only loose boost if your wastegate is leaking at high boost or maybe your B.O.V is leaking if you have one.

aron2063

yeah i was thinking that what happens is my wastegate stays open at higher RPM, because when i change my gears lets just say from 2nd to 3rd the boost goes all the way up to 7PSI and then it immediatly starts going down as soon as its there, it does sound like a wastegate problem but how do i fix it, thats the question, its just frustrating because its like my car is stock when im racing it becuase by the time i switch gears im already past 6300 RPM and im just runing 1 PSI, help me!!!!!!!!!!!!!!!!!!!!!

chingro

hmmm....

u say when u change gears the boost goes up then starts to go down...

where exactly did you attach the vacume line on the waste gate to?

and, where did you run the BOV vacume line to?