stuttering on load (acceleration)

Got a 66 mustang with a rebuilt 289 and a holley carb. A few weeks ago, I experienced a weird problem where, when I accelerated, the car started to stutter. I had about 25% the power I should have due to the
stuttering. It would run smooth when just driving, but whenever I pushed on the gas, this quick, even stuttering would come back. The next day it was gone. Now, about a month later, its back. Any suggestions on what to look for? BTW, I replaced the points in the distributor with pertronics a few years back...
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My first consideration would be secondary ignition.... under normal conditions, we wouldn't expect to see required voltage exceed 15KV or so. If we get into the pedal, required voltage (this is the voltage required to ionize the spark plug gap) increases. We may find a condition where the insulation on the wires can't contain higher than "normal" voltages or there may be a carbon tracking or moisture problem that allows higher voltages to "escape", following a route we didn't intend. Another concern could involve a faulty ignition coil or module that affects coil saturation (this refers to the strength of the magnetic field when the coil primary is turned "on"). If this magnetic field isn't strong enough, the coil may not have enough capacity to both ionize the spark plug gap AND supply current flow to initiate combustion....
HTH

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or there could be crap in your fuel system and carb

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IOW: Start with the wires and coil... then investigate possible carb problem. Distinct feeling of car falling on nose under acceleration is classic coil secondary symptom.
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