Some of the V8 2bbl carbs simply cannot supply enough fuel in from the idle circuit with today's fuel.( Some of the motorcraft 2bbls come to mind.) They need modified for today's fuel. So if you have a carb that is borderline already, throw in the smallest vacuum leak and you have lean condition.Like I said in post #24, pay attention to your idle screws. Start backing them out 1/2 turn at a time and see if you see an improvement at around 3 to 4 turns from bottom, let us know. I think we may be honing in on a problem.
