building a FAST legal small block

Adam, You post for fast, but dont really want to fit the rules? ;) That's different. You need J heads, witha good porting job, at least a 4" arm, and I'd run Solid roller with a bunch of other tricks. That "must sound stock" is EXTREMELY subjective. Ignore that part. If you dont care about the rules, just build a nice simple 408. A 408 with the cams you suggest wont get out of the 13s.