How to tune the autolite 4300 carb?

Double check your timing before you make any adjustments to the carb (made that mistake before). I always take the carb needles in to where they are just bottoming out, not too much or you will flatten out the point of the end. Then come out 1 and a half turns, usually a good starting point. From there hook up a vacuum gauge and adjust the needles until the engine runs smoothly and you get a steady vacuum above 20 inches. I used to have an Autolite 4100 to tune, but got tired of the "dead spots" in the acceleration and bought a Holley. Lost about 25% in gas mileage but she hauls butt.