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Not Boosting Past 4 Psi

bustafat

By bustafat,
in Engines & Forced Induction

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bustafat Contributor

bustafat

Posted
Posted

Guys

My engine is completely stock (stock boost)

only mod is a sports exhaust

i have a bit of a prob when im boosting

my car will boost nicely to mid way boost

when i hit 5rpm and im going into high boost the car wont boost any more

it sorta jolts and then accerlerated all the way to max revs, but obviously

not as it should

i though maybe it could be running rich cause of the exhaust

or turbo is blown,

or coilpacks are screwed

or airleek

any ideas anyone??

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r33_racer Grand Master

r33_racer

Posted
Posted

isnt stock boost 10psi and shouldnt it reach it way before 5k rpm. The better exhaust system you put in normally increases boost abit as it frees up the hotside from some backpressure.

Wait, is this a rb20 or 25?

r32matt Collaborator

r32matt

Posted
Posted (edited)

Yeah on a RB20 the stock boost is 10psi. It should hit 10psi at around 3500revs. The exhaust should also make it boost up quicker. Could be a leak in one of your lines or it could be your Acuator. My mates R32 was only boosting to 7psi, he put on a boost controller and it made 10psi no problem. :D

Edited by r32matt
r32matt Collaborator

r32matt

Posted
Posted (edited)

Ahh ok,

Well with the Rb25 you will get 5psi boost at first and then at 4500revs it will go up to 7psi. It has a dual stage boost solenoid. So it could be that which is broken or not working properly. Check the lines going from the turbo to the solenoid and see if there are any leaks. By passing the solenoid and just using a boost controller also might fix the problem, plus you will get a set boost of your choice. So you could run 7psi or 10psi straight away. Better than running 5psi and then 7psi.

:D

Edited by r32matt

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