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hey guys:

got a problem. ive got an rb25. ive just fitted a high flow tirbo (bearing and steel wheel). full exhaust, tubotech bleed valve, cold air, cooler. Whilst tuning it the guy says that its over boosting to 15psi in the high end boost range even tho its set to 10? it made 235rwkw?

any ideas why this may be??

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hey guys:

got a problem. ive got an rb25. ive just fitted a high flow tirbo (bearing and steel wheel). full exhaust, tubotech bleed valve, cold air, cooler. Whilst tuning it the guy says that its over boosting to 15psi in the high end boost range even tho its set to 10? it made 235rwkw?

any ideas why this may be??

turbotech does not have pre boost settings to work with, its over boosting because of a mechanical issue that is possibly related to the boost controller itself.

you need to play around with pre loads on the spring etc to get the controler working correctly. 15psi spike aint too bad for your setup, as long as its not leaning out and it tuned for it then you should just leave it

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sounds dumb but how long is ur bleed valve hose and where is it plumbed in.....just make sure the hose is as short as possible and picks up pressure as close to the intake housing of the turbo as possible, otherwise ull be prone to higher boost spikes

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sounds like a typical bad combination of wheels and a poor job on hi-flowing the turbo

they are the two reasons for OVERBOOST in your circumstance.

To be certain - remove the actuator, if its still doing it - 110% the turbo is a shit job.

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sounds like a typical bad combination of wheels and a poor job on hi-flowing the turbo

they are the two reasons for OVERBOOST in your circumstance.

To be certain - remove the actuator, if its still doing it - 110% the turbo is a shit job.

agreed im seeing so many dodgy high flows lately from so called small boutique turbo shops.

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Check your wastegate opening and what dump have you got? Some people have problems with splits for a dump and the wastegate has trouble opening or releasing the gas. Your boost tee could be another problem.

Borrow a friend's electronic boost controller if you can and see if that helps any.

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