You don't need to reinvent the wheel here. Talk to some builders with experience building boosted small block Mopars. The kind of boost you are talking about will require a race block and race gas to last long, as it should put out well over 600 hp. Electronic EFI with methanol injection would help a lot.
Why do you want to throw so much boost at it? 7 to 10 psi would be much more street friendly and dramatically less expensive to build a motor for. What transmission are you going to run? Are you going to back half the car to fit bigger tires? Just curious.