BOV not popping off!

[bboyt3nsk]

Well I just installed my Apex'i twin camber BOV and It wont Pop off and relieve the boost( on my redtop). After i let off the clutch or gas im still getting turbo shutter. Do I need more then 8PSI of boost? does it have a hard spring? I thought BOv's were supposed to releive all backpressure in the charge piping.
Im stumped. I also have a Greddy FMIC and Blitz exhuast

Thanks,
dave

[gasser]

did you hook up your vacuum line?

[BoostInnovations]

make sure its not all cranked down to hold like 30psi