[blykins]

My 425ci small block with Edelbrock heads, a very mild hydraulic roller cam, and a Vic Jr. intake made 484hp. So if this engine with the same cubic inches, 20 degrees more duration, .140" more lift with a more aggressive lobe, more intake and more carb, a 1/2 point more compression, lighter valvetrain, and a tad bit more head flow makes less horsepower, I'm leaving it at the dyno shop.