440 source heads on a stock 440

My Daddy, who built engines for NASCAR, told me there were three main secrets to making horsepower. The first two secrets were cylinder heads, and third and most important was cylinder heads. If you have a 7.5:1 compression engine making 350 horsepower and you change the cylinder head flow from 220 cfm to 250 cfm you will gain about 50-60 horsepower. That is why I posted the low compression 440 dyno test, that is what we saw when we changed the heads. On the same engine, if you raise the compression 2 full points, how much horsepower gain can you expect? Maybe 23 horsepower?

The Power Squeeze