I have done a complete tune up trying to diagnos a slight miss/stumble at idle and likely underway as well. I've got the following done:
Rebuild motor-w-maybe 20K on it.
Super six setup-w-Holley 2280 (Bad thing but I've got a BBD I hope to rebuild & install soon)
Pertronix electronic ignition
New wires, cap, rotor & Autolite #26 plugs
Fuel line mod
Electric fuel pump-w-clear filter so It isn't a fuel volume problem

I tried adjusting this carb but I've realy got no info on the procedure so I just set it at a low idle and messed-w-the 2 idle wixture screws until it got the smoothest idle. An ongoing problem is to get the idle in gear at about 750 so it won't stall it idles at aver a grand out of gear but this is just info and may or may not have an implication in the timing/stumble.

I put a timing light on it-I've got this tube thing that I suppose was from the 78 Aspen the motor came from but I see no purpose for it. The timing will show at about 3 degrees btdc and then fall about 3-4 degrees for one rev. That is when I can hear the motor go from very smooth to a slight stumble-not a complete miss. It will drop the timing between 5-6 steady readings and this is the only reason the engine sounds like a sort of miss.
I was thinking of changing the coil but would love some other thoughts.
Also I figured I would ask about any resources for a new BBD in case anyone knows of one.
Thanks
Howard
Hampstead, NC

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65 4-door Dart
70 Chrysler 300
2004 Cummins Ram 3500
1968 Dart GT Convertible-project
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