your better of dropping an ls in it, way better chance of hitting your goal, and trust me john, i know whats out there and i know whats not, i was in the lt1 community for a few years and i even had a 383 lt1 of my own, a built 396 with maybe dominion 32v heads on top of that thing and maybe you’ll hit 550rwhp, but those heads are pricey, and may not even be in production anymore. Or you can go with a nonstreetable solid roller setup and maybe hit your mark. Its a very bold statement, goodluck to ya, and im not saying you cant do it, im just saying when everything is all said and done, chances are you wont hit that goal. try something realistic like 450 -475ish, way more obtainable.