If there’s no one you’d trust with the basic machine work, who would you trust to port and/or do a valve job on your stock heads?
To make 400-450hp from a 360 magnum, you’ll need a cam that will require a valve spring change from stock.
The old MP crate motors hit 380+ hp. 9:1 compression with M1 single plane intake, and 750 Holley carb. Lots of duration, not much lift so they could use stock rockers.
