Boost Surge... I Think

[Joel Ross]

Hey, I just bought a r33 gtst and I have noticed that when I rev it up to around 5000 it seems to die out abit than the boost surges from standard 7psi to 14-15psi... The car had a manual boost controller which I had taken out back to stock and it still does it.

I spoke to the previous owner about mods and he done exhaust, two into one dump pipe, front mount intercooler, pod and was running between 8-10psi. He said it done it to him aswell and I'm concerned it will do damage.

Does anybody know what the prob is or heard about it? If so please let me know... Thanks

[Trozzle]

Leak between line coming off intake to stock solenoid, or line between stock solenoid and actuator?

[Moodles2]

Sounds like unlimited boost, check all your vacuum lines, it might only be opening up once the line in question hits 7psi

[DVS JEZ]

If the boost line is ok. Might be the wastegate fouling on the 2 into 1 dump pipe.

Might have to pull the exhaust off at the turbo to check it

[doo doo]

if the wastegate flap is catching on the dump pipe it will be stopping it from opening properly for the mentioned symptoms- you'd then be able to check it is opening properly by taking the actuator rod off and opening it by hand, no need to take the dump off to do this (the dump would need to be on to see if this was a problem). Or you could pressurize the boost line to the gate and see if it opens properly.