Car Misfires Continously Around 5500+rpm

[5ky]

just intalled a GFB bleed valve, set it to 10psi, took the car for a drive, i notice that around 5500rpm to 7000rpm the car would back fire constinoulsy liek it just goes "boop,boop,booop..etc", it seems the higher the boost i run, the car would misfire heaps earlier, liek i set it to 12psi then car started misfiring around 4500rpm to 7000rpm, when i set back to stock, car runs normal?

its a

r33 gtst

3` turbo back exhuast

pod

bov

hybrid front mount

what could be the cause?

[benl1981]

its either ECU going into rich and retard due to the extra boost or cracks in your coil packs.