Mindspin311

So last winter I had alot of issues with my BNR Stage 2 creeping to like 15psi on really cold nights. Other than making sure the wastegate is opening fully, which I believe it is because it holds 5.5psi perfectly, what can I check?

Wanked_FC

iTrader: (1)

Colder air is denser, not much you can do. I'm assuming since its a BNR, the gates are already ported.

backroad-junkie

iTrader: (3)

i always thought boost creep during cold temps and early mornings were due to the denser air. Is it always creeping during the cold temps or is it until the motor and turbo warm up? Do you have a BC? if its a manual then maybe theres condensation in it that keeps it from flowing or reacting properly...

Mindspin311

I realize that air is more dense. But 5.5 to 15, thats a bit much.

Wanked_FC

iTrader: (1)

I went from 8 to 12 in 40 degree weather... Its unusual, it'd have to be pretty cold. 5 to 15 is a lot.

SpeedOfLife

iTrader: (16)

it sounds like you mean that normally it doesn't boost creep at all, right? the way I understand it, if a wastegate isn't big enough to allow your excess air out quickly enough and you keep throttling it, I would think the boost pressure would certainly keep climbing until something blows.

RotaryResurrection

iTrader: (8)

Just the reference hose from the compressor to the wastegate, and the wastegate actuator/arm itself to see that it moves at the proper pressure.

Otherwise you will need a restriction in the intake or exhaust to slow it down.

Oddly enough on my FC, even with a bone stock turbo, small port, FMIC, intake, and full 3" exhaust, I COULD NOT get it to boost more than 8psi (bleeding down to 5 above 6k) with the WG hooked up. I even unhooked the WG (and capped the reference nipple) and did some pulls and couldn't get more than a momentary 12 that dropped quickly back to 8 and then slowly to 5.

I just put the GT35R on and an HKS 40mm (37 in reality) WG and it holds a perfect 8psi as long as I want to hold it at WOT.

IF you really want boost control you either have to run an external wastegate.