I bought a 94 Supra NA-T off of a guy...Right now the car is only running 7.5 psi of boost...I want to up the boost and I know I need to upgrade the head gasket...Which head gasket should I go with the Boost Logic 2.5mm, Powerhouse Racing 3.0mm, or any other suggestions??

With a new head gasket installed, what kind of boost can I run and when will I need to upgrade the fuel system...

Also right now the car has a t-67 turbo, headers, q45 throttle body, big fmic, 3.5" exhaust turbo back, custom intake manifold, cold air intake, Turbo XS RFL bov, and hard pipes....I have never had the car dyno'd, I was just wondering what kind of whp it's putting down and what else would I need to get atleast 450whp....

Thanks ZRO