all I know on motor is it has six pack pistons, bored 030 over, the cam stated above, my problem is as follows = tried to solve before but ran out of time had to go, anyway when I set idle @ say 800 then blip throttle @ carb then let go it will not return to 800 settles back in @ 1050-1150 and will not go back to 800 unless you loosen idle screw and start over. I did disconnect cable to rule out to tight, also checked for hang up. However when I do same test with vac hose disconnected from dist, idle returns to 800ish. Idle does jump around 20 -30 turns on the digital Tach/timing light, it is new. several guys said look hard at my distributor it is the mopar performance electronic dist ( very old 11+ years or so ) carbs are all redone.