Goin V-8

Since you aren't planning on replacing pistons this will be a low compression motor and you can't go very big with the cam or you will kill off all your low end power.

Something like a Comp XE262H (less than 220 degrees @ 0.050 in any case) would be about as big as you should go. Also since it's a mild build a large 4bbl is not necessary. A 600 CFM carb more than adequate.