That carb is junk, toss it and get a Double pumper. Check you tune. You should have at least 36* total timing at around 22-2400rpm. As mentioned see what the compression is. If your "rough idle cam" is a MP 509 or 484 and you have low compression that can be problem. Before you do anything take it to the track and get some baseline numbers. who knows maybe the guys dyno is off.