Liemoanh

I never get primary or secondary boost all the way through redline. The only way it comes on is that if I'm going in any gear than down shift and floor it past 5000 rpms than I start to hear it spinning and I get 8 pounds of boost, which I think is coming from the second turbo. If I let the rpms drop below 4000 rpms then boost build really fast to about 12. Than if I shift to next gear 50% chance the boost will stay, If not I have to do it all over again. What is going on. What acutator is causing this. Someone please help me.