440 what am I missing here?

Here is a cam test that I ran 20 years ago using a Mopar big block with HP manifolds. The engine was very sensitive to the camshaft design. Smaller worked a lot better than bigger that is for sure. If the cam was too big then it lost power down low and it couldn't make power up high. If the cam was too small it made great power, just not a lot of it. With the correct cam it would fry the tires.

http://www.moparts.org/Tech/Archive/bb/550hp.html