On my 1978 K20 with a 350 4BLT main, I swapped in a Comp Cam 280h 12-212-2, double timing gear on the key way for 4* of timing retard. I previously had an edelbrock intake, 1.5 roller rockers, MSD cap, rotor, and a Digital 6 plus box, a 750 manual choke carb.
I got everything in and situated...