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Had a dual stage boost controller fitted today.

I wanted high boost to be 14psi and low to be the stock 7psi. However for some reason my mechanic couldnt get low boost below 11-12psi.

Does anyone know why this could be? He suggested that possibly the car wasnt running 7psi when i brought it in, however to my knowledge it hadnt been boosted before...

Mods include large FMIC, 3" turbo-back exhaust.. (if that makes any difference)

Any suggestions on why the boost would not come down would be most appreciated...

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With everything dead stock inc. the cat convertor that was no bigger than my fist the boost was hanging around 8-9psi and made 115rwkw, 125rwkw with the fuel pressure tweaked to lean it out a little.

I then slapped the exhaust on and it made 10.9psi.

Then the bleeder was fitted and it bumped low boost setting up to around 11.5-12psi. With the fuel tweaked it made 152rwkw on 12.5psi. Low boost and high boost felt hardly different with highboost mainly having a bit more in the mid.

I then fitted the ebc and found that it was the restrictor that was causing the boost to hold a little higher.

With the EBC it is now back to 10.9psi.

16psi on High boost, I never drive it on low boost as it feels to gutless.

The RB's love boost :P

nah its those crappy turbosmart controlers.

i had the exact same problem as you, couldnt run less than 13psi with either a 2 stage or a bleeder. wheni removed it all together i could hold 8psi and i have cooler, exaust, dump, filter.

i think the valve cant seal off properly or something.

by removing it or changing to ebc there was no probs in running std boost levels.

Hang on i thought R33s ran 6psi and R32s 7psi (certain of that because the factory boost gauge says 7)...

Anyway when my mechanic cable-tied the tube to the b/c (thus "removing" the b/c), it showed stock boost levels.

Benny i think you're right these cheap b/c's cant seal properly.

Mine peaked at 12 then dropped to 10 with front mount, pod and exhaust, no controller.

Turbo smart peaked set to peak at 14 then dropped off to 10 or 11 cos stock wastegate couldn't hold, NO SPIKES. Low boost setting went up to 11psi dropping to 10.

HKS actuator fixed that. Got it set at 12 flat in low boost mode, peak at 15 in high dropping to 13.

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