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Ive got an R33 with the stock turbo on the RB25DET

Now ive heard different stories so it seems the amount of boost the stock turbo is debatable.

I recently installed an R34 SMIC on my car and was wondering what PSI i could comfortably run the stock turbo at? Without risk of damaging it or any other parts.

Im wanting to crank it up to at least 10 PSI, but 11 or 12 would be better, is this possible? Has anyone else done this and what was the result? And how good is the stock turbo?

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i have the r33 series 2 turbo on my r32 gtst and i run 15psi high boost and it hasnt faulted me but low boost is set to 10psi what usually gets drivin round on but i think with the African American engine u should stay 12 max!

holy shit i just said the african american engine hahahahahahaha trippin... was ment to say witth the bigger engine should stay 12 psi max

^^ lol WTF haha

Anyway I rann 14psi on mine.....and it eventually snapped the shaft so i would be keeping it at around 12psi too, it starts to make more het than power after then anyway as it is well and truly starting to run out of puff

I run 12 PSI on stock ECU & catback with no issues so far (6 months), 150rwkw on a mainline dyno.

But anything above stock be prepared you are taking a risk, stock 33 turbos can be picked up sub $400 if you do pop one though.

I'm on a budget but have similar setup

running 10psi with no dramas on r33 with catback and r34 smic

next step is dump, fuel pump and safcii

12psi should be fine as long as your not doing circuit work,

eg constantly on boost. Occasional blat like on public roads

won't get ur egt's that high

interested in results rb25 owners have from vg30 steel

wheel turbos. Seem to go cheap and bit tougher

Sorry, i didn't mention, i have fully replaced the exhaust system, including the dump pipe. Had it custom made 3inches all the way back.

Im running it at 10 PSI and it seems to be working fine, but with this set up you guys reckon dont push it past 12? until i get an aftermarket ECU?

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