i have a 72 302 with a motorcraft 2150 2 barrel carb on it, im getting hesitation on light throttle, im running 49 jets on it i was thinking of getting 54s for it, im thinking it might be running lean. anything else could be causing this? i have timing set at 10btdc, new points, condensor, coil, spark plugs, and wires, cap and rotor too. does it under load, and when its just parked.
make sure accelerator pump is in good working order and if so see if it has another hole on the arm to adjust for a bigger squirt. mines not motorcraft, but it has a summer/ winter setting on the arm (2 holes for rod in different locations), basically leaner in the summer and richer/bigger squirt for winter.
Don't increase the jet size to cure an off idle stumble. You'll probably end up making it too rich in the main circuit and power circuit where I'm guessing you don't have a problem. As already mentioned, a lean tip-in from idle sounds more like an accelerator pump issue. If you're running a choke, make sure it's adjusted properly. And when you set your initial timing make sure you disconnect the distributor vacuum advance and reconnect it after you've locked down the timing. Should probably be connected to full manifold vacuum, not ported vacuum.
i just got it sorted out, it ended up being the points, put the old ones in and its running smoother than ever
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