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Put a boost tap in last week and have been playing round with it. My car only has the standard gtst intercooler. Could someone experienced and mechanically minded tell me what the max boost that I should run it on without the intake temps getting too high or the a/f mix becoming lean. Seems to hold 12psi fairly well.

Cheers

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I personally run ~9.5psi with full exhaust and it's fine.

With summer coming, I wouldn't want to run anymore through the standard cooler personally. You're risking too much money for a couple of extra KW :D

huh, i personally wouldnt go over 11 psi to be safe with a bigger intercooler

13 is to much for stock turbo

Not worried about the turbo. It puts out fine. Im worried about the piston and rings. Thats it.

One other question. Is the car speed limited? I've nearly reached the top of 5th and haven't found one, yet people tell me it's limited to 180km/h.

serious? u held 14psi wit standard ecu, standard computer?

god mine wouldnt even let me get to 14psi...cuts out

not even 12psi

well count urself lucky, if the ecu let u do that, u would soon have no turbo, and possibly more problems, 12psi is within the limits, possibly even 11psi, push it more and ur asking for some trouble

Not worried about the turbo. It puts out fine. Im worried about the piston and rings. Thats it.

One other question. Is the car speed limited? I've nearly reached the top of 5th and haven't found one, yet people tell me it's limited to 180km/h.

are you really doing 180 ?

when they are imported they are fitted with an 180km speed limiter as part of compliance, this is easily bypassed and removed, so its possible that its removed, technically u shouldnt be able to top out 4th (on a manual)

which i have never tried, cause those speeds on the road are a little bit stupid u know ...

10psi for me, never any more.

and if u reached the top of fifth(250km/h) u have your speed limiter removed

at higher boost you should worry about your turbo not your motor. the standard ecu will go rich and retard and it should feel slow anyway.

serious? u held 14psi wit standard ecu, standard computer?

god mine wouldnt even let me get to 14psi...cuts out

not even 12psi

lol... my car is well looked after. Im an apprentice mech.

plus I put out the exta dosh for bp ultimate :D

Not to mention that the turbo would be working harder to push that much air through the stock cooler (as I've been told they are pretty restrictive)

Personally, I'd recommend no more than 10psi. Who knows, if your turbo blows, you could end up with nasty bits in your engine, not really worth it....

Not to mention that the turbo would be working harder to push that much air through the stock cooler (as I've been told they are pretty restrictive)

Personally, I'd recommend no more than 10psi.  Who knows, if your turbo blows, you could end up with nasty bits in your engine, not really worth it....

Thanks Tomm0. This is exactly the sort of stuff I want to find out. Thats something I haven't thought about. What damage could it cause if the turbo blows?

lol... my car is well looked after. Im an apprentice mech.

plus I put out the exta dosh for bp ultimate  :D

it does not matter what fuel or what u are, if u run 14psi the turbo is sure to die soon after some hard use. do a search on stock turbo and u will see why, but simply put, the exhaust wheel is ceramic, and does not handle heat well.

haha whoaaa watch out people, hes an apprentice!!! lol just joking, yea i use the good fuel also...

Coupe This: i had no intention of running 14psi! it was set to 12psi....held it flat up a hill...major cut out, dont want that again, dont even want it at 10psi, raising the boost wit mostly standard parts dosnt enhance performance at all, car runs slower at any boost above 9 or 10 or 11....its set at standard until i put my power fc, bosh 040 pump, fuel presure reg and cam gears in, than i will have it at a max of 12psi

It's more a matter of keeping the heat as low as possible. The figure most people use is 13psi, but if you go on track days it might blow up at 11psi due to the heat, simply too hard to predict.

With a FMIC, most people run 12psi without any problems.

Dont intend on going to track days until I have all the stuff to handle long periods of high load. At the moment I only give it hard for a couple of minutes at a time. Or drag it on the quarter mile.

Cheers for the productive answers Tomm0

10psi sound like the go till FMIC is in then i'll see how 12psi goes.

Edited by r33nut

I would have wagered a bet that your turbo would have blown within the month if you kept it running at 14psi.

Its all about what you want: A quick high or reliable buzz?

I dont really understand how it works but from what I've read, the stocker experiences diminishing returns after 12psi.

Personal recommendation? I reckon keep it at 10psi until you get a FMIC, especially with the hotter summer days approaching.

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