So been struggling with carb issues and a coil breaking down when hot. Replaced the coil and sent the carb out to Guarantee carb in FLA. My question is now as I throttle it up it wants to black smoke. When I drive it and throttle it up it smells like it's rich. I have fooled with the idle air screws , but to my knowledge these to nothing once throttle is given . They where set about 5 and half turns out when I got it back . I turned them in to around 4 turns out. If i turn them in to say 2 1/2 turns it runs very poorly. At 4 it runs very smooth and on the vac guage it holds almost 20. Do i need to step it down jet wise? I'm not a real good carb turner , but a decent mechanic and willing to learn thanks Lance .