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First of all hi there guys this is my first post. I bought an R33 yesterday and it already had a heap of mods like FMIC, TBE, CAI Custom plenum etc etc. It was misfiring over 5000rpm so i change dthe plugs and checked the boost levels which were at about 10psi... Once i changed the plugs the turbo seems to be making a "screeching sound" but the misfire has gone. I assume the turbo has shit it itself so im really lost as what to do... I really want to keep it without lag so im not chasing big power and want to keep it fairly cheap so any info would be greatly appreciated.

Was thinking maybe just get this one hiflowed? Is it worth it? Really want a bolt on part though.

Cheers Graeme

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ttimtams - please search.

RB25 turbo upgrades are a dime a dozen

However, screeching i would say is probably a leaky cooler pipe

hmmmmmmmmmmm Pulled it apart and gues what.... Turbo is fine! its a ceramic turbo which is ewwww i think. Whats the limits of these things? It turned out to be three broken ex studs in the head!!!!! Thats gonna suck to fix! Any ideas? Not too keen on removing the head but what else can i do? It was missing so i put plugs in it and the first time sinced i owned it (48hrs) it revved clean to 7000rpm and pop went the ex gasket on the manifold gasket due to the extra ex pressure and lack of bolts!

Oh the joy of modified cars

hmmmmmmmmmmm Pulled it apart and gues what.... Turbo is fine! its a ceramic turbo which is ewwww i think. Whats the limits of these things?

12PSI is safe if you wish to keep it healthy.

14PSI is borderline, but you may end up spinning the wheel off the shaft over time.

Edited by dmr
12PSI is safe if you wish to keep it healthy.

14PSI is borderline, but you may end up spinning the wheel off the shaft over time.

Awesome thankyou! I think 12psi will be great.... The manifold was REALLY hard to remove due to other bent studs etc so was thinking maybe it would be a good idea to bolt on an aftermarket one like this maybe: http://www.japparts.com.au/products/Header...ges/rb25lmm.bmp

But do you know if this leaves everything else in the "standard position"?

Or this one?: http://justjap.com/store/product.php?produ...=274&page=1

Edited by timtams
Awesome thankyou! I think 12psi will be great.... The manifold was REALLY hard to remove due to other bent studs etc so was thinking maybe it would be a good idea to bolt on an aftermarket one like this maybe: http://www.japparts.com.au/products/Header...ges/rb25lmm.bmp

But do you know if this leaves everything else in the "standard position"?

Or this one?: http://justjap.com/store/product.php?produ...=274&page=1

i personally wouldn't advise going with a stainless steel manifold. they tend to crack at the welds at high temperatures and cause alot of vibration. gas temperatures can reach up to 900 degrees celsius at the manifold.

the standard cast manifold is designed to take the heat and vibrations rather than send it further down to other parts.

a friend of mine had problems where his dump pipe bolts would come loose constantly, and after he went back to the standard cast manifold he had no more issues.

if you were still considering stainless steel manifolds, i would think if it's a quality made low mount product that it would fit up perfectly to the standard setup. but any cheap copies or chinese made products will probably cause issues.

Edited by dmr
i personally wouldn't advise going with a stainless steel manifold. they tend to crack at the welds at high temperatures and cause alot of vibration. gas temperatures can reach up to 900 degrees celsius at the manifold.

the standard cast manifold is designed to take the heat and vibrations rather than send it further down to other parts.

a friend of mine had problems where his dump pipe bolts would come loose constantly, and after he went back to the standard cast manifold he had no more issues.

if you were still considering stainless steel manifolds, i would think if it's a quality made low mount product that it would fit up perfectly to the standard setup. but any cheap copies or chinese made products will probably cause issues.

Thku very very much, i think i will stick to the cast one for now and somehow replace these studs! I really do appreciate you taking the time to post

Cheers Graeme

Thku very very much, i think i will stick to the cast one for now and somehow replace these studs! I really do appreciate you taking the time to post

Cheers Graeme

np :P

and as nismoid said, make sure to replace ALL your studs and not just the broken ones.

np :P

and as nismoid said, make sure to replace ALL your studs and not just the broken ones.

Dont worry after all this work and worry i will! I can get my hands on a Garrett Dual Ball Bearing 3076r Turbo i think i might do it now as it has a fair few mods already with a stck turbo so while its off i may as well i think. i already have a FMIC, TBE, CAI, Forward facing plenum etc so with a decent turbo and some bosst on board i think it should be ok, any ideas what sort of boost i could squeeze into it safely with stock injectors etc and what sort of power i could expect?

Ok for the first time since owning this car i can finally rev it out to the limiter, im actually surprised how well it goes! Its sits on about 10psi and spikes to 12psi at about 6000rpm.

The job of removing old broken studs...well..... Farkin sucked! But now the are all replaced with nice new ones and new gasket etc it really gives me piece of mind. So thanks guys for your help and advice it really helped.

Cheers Graeme

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