Update...Problem still there
new plugs, rotor, cap. Old cap looked as if the rotor was not centered. I will check this in a couple of days. No play in distibutor.
Compression, All cylinders were equal.
PCV was causing some of the backfire, This and adjustment on the carbs resulted in 20 in hg for the vacuum.
I took an old plug wire and tried each cylinder and there was no difference, My test meter is broken so maybe a resistence check tomorrow.
