Hey guys,

I'm currently starting to tune my new build. I'm still at wg pressure. What I've noticed is that if I boost in a gear, say 2nd, I hit my 11-12psi and hold it till 7k. however, If i boost from 1st, into 2nd, I only hold 7ish psi after the shift and this persists until maybe 6k where the boost then creeps up to the 11psi again.

I suspect the dv may be leaking? I have a greddy RS recirc. I tightened down the adjustment all the way, still no change. any other ideas?

Thanks.

 

Remove the DV and plug the empty orifices in the UICP, MAF hose, and the reference line from the IM. Try driving and shifting this way with the DV out of the loop. This test should immediately answer the question as to whether of not the DV is at fault. Or, alternately swap out the aftermarket BOV for a stock DV, strictly for comparison's sake.

 

Are you still on the stock turbo?

 

How are you controlling boost?

 

im running straight wg, no solenoids or controllers etc.

its a 9 turbo on a 6gsr

 

The diaphragm in that diverter valve is notorious for wearing out and developing a hole making it pretty much useless.

 

Maybe it's what the fireman says. Because 7# is way low! Base WG pressure is usually between 10-11#.

 

And the diaphragm problem tends to be more intermittent, sometimes you get boost next run you don't.

 

Ouch, fix that asap!!!! :x