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anyone else have this problem? im having a 1psi spike @ 6,000rmp, im running 10psi(so 3 psi more than stock) and in the higher revvs i get a slight spike, could it be its not tighted enough?

What the genral causes of boost spikes?

thanks

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Boost spike can come from 2 area's

1. Boost control unit

2. Boost creep - The wastegate is too small and there is not enough exhaust flow out.

I think in your case, only 3 psi above stock, should be answer no.1

a 1 psi spike I wouldnt think is a real concern...  what are you worried about?

because the car jolts when its spiking between 10 and 11psi

.....

Its a steady 10psi all the way up, and jolts @ 6k but goes away at 6.200-7,500

this is on a rb25det aswell

anyone know where I can get one of these suckers? i tried pm the guy who sells them ,but no reply..........any help guys?

i emailed him, his email is in the first page of one of the threads, have paid the money on sunday so should hopefully get it soon, haven't heard from him though!

Most boost gauges are pretty poorly calibrated, chances are you're really running more than 10psi, spiking up just too high and hittingR&R as mentioned. Wind it back until it's okay, but if you want finer control, spend some real money on an EBC.

mine works fine was one of the first to get one have had no problems at all i run 18 psi no spike no drop off

(if wastegates have anything to do with it i am running a 38mm externall gate)

um im actually assuming that its still connected to the factory solenoid and its moving from the low boost setting to the high boost setting...

if u know how to correctly set up a boost controller then manual ones can acutally work better than mechanical

If your getting a spike at 6000rpm during accelerating them its not the boost controller. Its something else. :P

The ball/spring type boost controller will only cause spikes when you initially jump on the throttle and it boosts up really quick, slightly overshooting the mark. The other time it will spike is when peak boost is made while accelerating from a low rpm. Allthough not as common or noticable as jumping on the throttle and have it instantly hit boost at higher rpm.

I've had 3 types of manual boost controllers.

The $22 boost controller, a ball/spring/bleeder and a simple bleeder all did the above.

For $22 the manual boost controller being sold works just as good as the others being sold for $100 odd.

A friend tried mine and said it was better than his GFB boost controller.

ok it seems it wasnt spiking, it was missfiring hence the jolting, and it just happpend to happend when the needle went to 11psi, i fixed the missfire problem now it runs fine, and holds boost perfectly!

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