mousemod

So I just bought a 1973 240Z with an H code 1968 SBC 327 coupled to a T5 5 speed tranny. I have the original 240Z differental in her and am worried about that old girl exploding. Does anyone know a proper replacement to hold the power? The 327 has been bored .30 and at some point it has had the heads and cam changed to some crazy high compression combo. Just feeling leary about giving the Z the whole gas pedal. any input would be appreciated. pics comming later.