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Overboosting At 5000rpm

mags33

By mags33,
in Engines & Forced Induction

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mags33 Newbie

mags33

Posted
Posted

Hey guys, have an overboosting problem with my r33 gtst s1 with the wastegate fully open. It makes no boost with the gate open until 5000rpm where it builds up very quickly to 14psi + . Being a GCG highflow I sent it back to them thinking the wastegate needed to be bored out. . The wastegate was bored out to the largest size possible with a new flap assembly. Got it back and still have the problem. I have also checked the cat for anything restricting flow and that the wastegate is not rubbing on the dump, both are fine.

mods:

power fc

power fc EBC

GCG highflow

batmbl dump

3in exhaust after cat

any thoughts welcome, cheers...

mitch.

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WogsRus Veteran

WogsRus

Posted
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my mate has same problems, exacty thesame. Give a ydawak PM. he is usually on every couple of days. But so far the turbo has been off 3 times to fix it, turns out the way the turbo was put back together, ment the westage was not openning fully or something. He has yet to get the car back after having everything put back together, so wait and see

r33_racer Grand Master

r33_racer

Posted
Posted

check you have the hoses for your ebc plumbed in for internal gate, not external. There are three possible fittings on the solenoid unit, i think you want for internal the middle one and one of the side ones..check the apexi handbook for setup.

WogsRus Veteran

WogsRus

Posted
Posted

it's actually something to do with the angle of the wastgate actuator to the push rod that opens it. My mate, broght a CGC turbo, same problem, it was ok on the bench, but as soon as it was bolted to the car, and the wastage rotaed round to fit the engine bay, it simply made boost and it could not be limited back.

mags33 Newbie

mags33

Posted
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Posted
check you have the hoses for your ebc plumbed in for internal gate, not external. There are three possible fittings on the solenoid unit, i think you want for internal the middle one and one of the side ones..check the apexi handbook for setup.

Hey guys thanks for the replys, the ebc should not come into play because the actuator arm is disconnected and I wired the wastegate open, so it shouldn't make boost, but it still does..

thanks again for you imput...

cheers mitch.

cameron Mentor

cameron

Posted
Posted (edited)
Hey guys thanks for the replys, the ebc should not come into play because the actuator arm is disconnected and I wired the wastegate open, so it shouldn't make boost, but it still does..

thanks again for you imput...

cheers mitch.

Woop,

Another one that does the same, unsolved mistery!

This is the 4th R33 that has this problem...

We have just about tried everything from dumping the exhaust to getting a new hks turbo! still boost creep at 5000rpm...

Same thing with the wastegate flap fully open, makes 15 or so psi!

Oh with the flap fully open it will make some boost should be a max of 7psi at around 7000rpm... but 14 and more aint normal.

Edited by cameron

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