[frdfver]

I’m sure that the parts and assembly at ford had quite a lot to do with the variances in horsepower. I know from my own experience working at a ford dealership in the late sixties that we could have identical equipped 428 cobra jet mustangs and more often than not one of them was faster than the other. I had a 1971 Mustang 351 cleveland stone stock that was significantly faster than any of the others , all the right parts and balance must have come together in that engine. Big difference between hand assembled engines from an engine builder and one that is built on an assembly line.

Paul