Just looking for a little help here. I've got a 427ci generation IV motor with forged pistons, 10:1 compression, Magnum 520 lift hydraulic cam, weiand stealth intake, 750 Vac. Secondary carb Holley 3310, Msd ready to run dizzy, Hooker Headers, Flowmaster dual exhaust, 290 GM Heads from 1970 with the larger valves stainless and correct springs for cam.

How much horsepower would you guys say I'm putting out? It's hooked to a 4spd muncie and 12 bolt posi. Thanks

Around 475 -500.

My computer guesses more like 425 fwhp as it sits in the car.

Thanks guys I appreciate the quick response. I was thinking around 400 - 425 but now after your input its probably closer to at least 425. It's in my 72 nova I just wish I could plant it, a real pain to launch without spinning. My gearing is 3:42 posi with an M20. Upgrades will be CalTrac or SlideALink bars and a Tremec 5 speed. Thanks again. Bill/Naples