It is stock electronic ignition as far as I know. Voltage at battery with vehicle off is 12.55v. Voltage at positive post of coil key on engine off is 4.7v. Voltage at positive post of coil key on engine on is 7.2
I have it running, and when I turn the distributor counter clockwise or advanced, it pops louder and more often. When I retard the timing and can actually see the timing marks with my gun, it pops less or almost never until I put a load on the motor. I actually drove it today and it had absolutely no power and began to backfire a lot (after idling with no popping for 5 minutes). My next free time is Sunday and I am going to do a compression check. Can a carb load up and cause exhaust backfiring only?