3 carbs look sharp, sometimes the inner carb fouls the fender brace rod.A single 4bbl is easier to do.If your engine is modified ,about 500-600 CMF should be ok for street use.Keeping thing equal,rating all carbs for flow like 4bbls, the Holley Weber 2bbls flow 200cfm each, Rochester and similar sized 1 bbls about 125-150 cfm.Your Holley is the original style carb?
