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Hey guy's, im having major troubles with boost. I upgraded a bunch of stuff...

PFC

high flowed turbo

FMIC

high flow injectors

fuel pump

all the usual stuff. on the dyno when tuning it gets to 15psi then drops way down to 9psi. only got 160rwkw!!

the things we have checked...

sent turbo off to be tested, was ok (including actuator)

tried 3 different boost controlers

clamped the BOV line when on the dyno

thats all i can think of but we have been trying to work it out for a few months now. before the upgrades it was holding 12psi fine. any ideas would be muchly apriciated, thanx guys

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have you tried putting more preload on the wastegate actuator?

is your exhaust restricted in any way?

other things to try would be to see if you've got any leaks in your intercooler piping by hooking up a compressor to one of your vacuum lines and blocking off the intake. then just spray some soap around silicon joiners, vacuum hoses and the plenum to runner gasket and see if anything bubbles up.

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have you tried putting more preload on the wastegate actuator?

is your exhaust restricted in any way?

other things to try would be to see if you've got any leaks in your intercooler piping by hooking up a compressor to one of your vacuum lines and blocking off the intake. then just spray some soap around silicon joiners, vacuum hoses and the plenum to runner gasket and see if anything bubbles up.

we took the cat off and drove it so only the dump and front pipe were conected (loud as f**k and run shit) but it still did it. I did put more preload on the actuator. the air compressor cooler piping trick was what i was goona try next, so it looks like thats what i need to do. thanx for the help mate, any other thoughts are VERY welcome as im getting really over this, just spent 5k on my car and its no better then it was lol!

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the standard dump pipe starts to get restrictive after around 14psi ive noticed (its very narrow around the wastegate exhaust port) so it wont really matter if you ripped the cat back off. do you have an aftermarket exhaust or is it still standard?

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the standard dump pipe starts to get restrictive after around 14psi ive noticed (its very narrow around the wastegate exhaust port) so it wont really matter if you ripped the cat back off. do you have an aftermarket exhaust or is it still standard?

yeah its got a high flow dump/front pipe in one, into a 3.5 inch system.

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https://www.sau.com.au/forums/topic/203471-losing-boost/#findComment-3610077
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hear any strange noises?

there is another thread in this section and that guy is having leaking problems.

nah i cant hear it leaking or anything. i just tried the compresor trick and it just went straight through so i didnt block somthing off that i should have. the line into the actuator held 60psi but all the other lines held 0psi. :)

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