OK!
Someone with more knowledge than me might know about Pontiac Head interchange. I believe if you use any heads other than 1955-1959, you would have to re-design the cooling system of the motor. That might require using a 1960 front timing housing. 1960 pontiac motors were side mounted in the front.
1959 motors have the side mounts cast into the block, but can use the bottom timing cover mount.
My 1959 pontiac motor has the stock 1959 heads with hardened seats for the exhaust.
I have mine built to run on 87 octane pump gas. I have a very mild cam. My engine idle is set at 500 rpm, and the truck will pull hard to 5000 rpm. After 5000, the valves seem to float a bit. My motor really takes off when you get into the secondaries above 2100 rpm.
