My 1966 Stang is a 6 cyl and runs great absent hesitation upon acceleration. We have cleaned the carb, replaced plugs, wires and distributor. What else should we be looking at? Again, the hesitation is only upon accelerating, and otherwise runs even.
first get rid of the stock load-o-matic dist, and replace it with a duraspark dist from a later model small six. i got one from a 78 fairmont, and hooked it to a chrysler ignition box. it works great. second add ignition timing untill you get detonation, then back off the timing a few degrees. that should eliminate the hesitation.
Could be a carb issue in the accellerator pump circuit.
There is more to it than just cleaning the carb.
There are usually adjustments to be made in that part of the carb.
If you open the throttle plates without a shot of fuel to carry the carb into it's main circuit, then you just get a 'hole' in accelleration until the main can catch up to your throttle plates.
That said, I don't know your carb in particular.
However, I know about carburation in general and the principle is the same.
Do some looking and find out how to adjust the carb you are dealing with.
Dave