What chassis dyno?

Rear wheels/tires?

Exhaust after headers?

If a dynojet, my guess is-

630rwtq @ 4200

525rwhp @ 5500


If a Mustang dyno, -10%

If tubbed on huge wheels/tires, -40rwhp

If exhaust is smaller than dual 3" -or- any muffler design other than straight through. -40rwhp

I think it would be difficult to make 750 with 325cfm and that displacement/cam/compression so thinking it will sign off a bit early.