We have just finished picking up my sons supercharged 383 that he is putting into a 72 z28. We have a 700r4 trans that came out of an 89 iroc sitting in the garage. How strong is this trans and how much hp can it take in modified condition? The dyno sheet showed 618 hp and an avg of 400+ lb/ft or torque. He would like to use an automatic as opposed to a manual if possible.

 

The 89 was the first year of the upgraded 700. I would definately spend the extra money and upgrade the reverse input drum (sun shell), the planetary set and put a shift kit in it. The trans will probably hold for a little while but it doesn't make sense to put it in and hope it will hold instead of starting fresh with upgraded internals. If you do it yourself you can save a small fortune. Don't be intimidated by it.

 

I know a guy running an 800hp when supercharged 383. backed by a built 700R4

he blew it up after 4000km, and he rarely ran it with the blower on it,

turbo 400 is the way to go