I'm not trying to be an ass hole but do you have a tuner or a shop that you work with? They may be able to get you dialed in. The car may be tuned not to boost over 20 PSI.
cant get boost over 20psi
04 sti, Garrett 3076r rotated turbo, 860cc injectors, forged internals, turboback exhaust, hks bov, tial wastegate, with a manual boost controller. bought the car a few months ago and just now started toying around with the boost controller and i cant get it to boost over 20psi. Accesport tells me its tuned for 18.5 psi and when i got it it was turned down to 15psi. i turned it up a few clicks and was reading 20psi for a few weeks, and i decided i wanted to try a little more, but it wont go over 20psi no matter what i do with the boost controller and i want to try some bigger boost since the car is built for it ..im still new to the turbo game so please dont flame me if i asked something dumb but i still dont know how all this stuff works.
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^^ exactly, just because you have a boost controller doens't mean to turn it up, forged or not.. That car was tuned for 18.5psi, so you really shouldn't be messing with it anywhere above 18.5psi. You'll need to go to a tuner, and get tuned for higher boost.
inb4thespunrodbearing.
OP talk to your tuner before you damage something.
OP talk to your tuner before you damage something.
lol. yeah sorry boss, you'll have to get a map for 20 psi, you cant just manually override the computer with the MBCS
Going to be brutally honest here.04 sti, Garrett 3076r rotated turbo, 860cc injectors, forged internals, turboback exhaust, hks bov, tial wastegate, with a manual boost controller. bought the car a few months ago and just now started toying around with the boost controller and i cant get it to boost over 20psi. Accesport tells me its tuned for 18.5 psi and when i got it it was turned down to 15psi. i turned it up a few clicks and was reading 20psi for a few weeks, and i decided i wanted to try a little more, but it wont go over 20psi no matter what i do with the boost controller and i want to try some bigger boost since the car is built for it ..im still new to the turbo game so please dont flame me if i asked something dumb but i still dont know how all this stuff works.
You are playing with fire since you don't really know what you have or what you are doing. If it were my car I would start at 14 lbs. and slowly work my way up to 20 PSI while datalogging A/F ratio, feedback knock, and load.
IF the car is logging zero knock under full load and is running at least 11.5:1 AFR I would go buy about 5 gallons of 109 oct. fuel (MS109) and mix it into a tank of 93 octane. Then I would try to push it to 22 PSI. If the boost won't go over 20 PSI then you need to compare your 20 PSI logs to the "22 PSI" logs and see if the load has shot up. This is a sign of a boost leak somewhere, and you'll have to go find it. If the load has not gone up and boost stays at 20 PSI then the wastegate is not allowing the turbo to output that much pressure.
If you don't know how wastegate and boost control systems work, then stop there and go find someone that does. One simple mistake with boost controls or wastegate plumbing and you'll soon be the buyer of a brand new shiny motor.
My feeling is that the tune you have is for pump gas, hence why it stops at 20 PSI. Running more than that on pump gas is risky business without some way of preventing detonation (water/meth).
your pushing all that through the stock downpipe?
your pushing all that through the stock downpipe?
nope.04 sti, Garrett 3076r rotated turbo, 860cc injectors, forged internals, turboback exhaust,
But the OP should seek a tuner.
:rex1:
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