Update: I think I fixed a vacuum leak that caused a "stumble", but now I am evaluating a backfire (through the carb) that occurs at low RPM in 4th or 5th gear.
Update 2: FIXED. Read on to get to the dramatic conclusion of this detective story!
I have been having a little stumble just as I roll off the "no throttle" position.
It doesn't seem to be directly linked to RPM, as it basically occurs in every gear. In the higher gears (4th and 5th) it now results in a "lean backfire".
Once the motor gets over this "weak spot" it seems to pick up and run fine.
Checks of the linkage show the accelerator pump squirting gas from the nozzle as soon as the linkage begins to move.
Carb is a Braswell (Modified Holley) 700 CFM / 4 corner idle.
I would suspect carburetion because of the non-correlated effects of RPM, but I have had a similar problem that was related to the distributor shear pin a couple years ago (retarding my timing)....
Ideas?
I have also isolated the 5-6 wires from each other, and this had no effect.
It seems to be getting worse....
Rocky
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