IS 700 HP POSSIBLE WITH......

I could see going 700 hp if your last engine was 650 hp not 350 hp and the cars primary purpose is racing, plus gonna be slightly hard to experience all 700 hp at 7000 rpms at normal street speed, then there's the expense of getting the rest of the car 700 hp capable.

This is not directed at the OP, I have no idea of your circumstances.