There was a great article a few years back in one of the magazines(Super Chevy or maybe Chevy Hi-Performance) called the "Frankenrat". It was all about this motor and some upgrades they did. The combustion chambers on those rect port heads are the size of the Grand Canyon..if you can get the compression up to about 10.5 to 1 and add some cam..you will make a lot of power. We also used the Edelbrock Airgap RPM manifold. We didn't change pistons..just milled the aluminum heads(oval port)..that limits cam timing because of valve clearance issues. If I did it again I wold just use the bare 4 bolt block and build from there. I will try to find that aticle and post it for you.
wilma
