being a 69 the flexplate should not have a weight on it,nor should the dampner have a weight behind itThanks for the input, guys.
I've had the engine apart several times.
The flywheel was skimmed and balanced during the first rebuild in 1983.
The entire reciprocating assembly has been checked every time I have changed components.
I have had a LOT of trouble getting the timing right over the last few years, and I now know the outer ring of the original damper, which also drives the water pump and alternator, is moving around. Each time I check the timing marks against TDC established by the positive-stop method, the marks are in a different place (32 degrees out last time - advanced - next time it'll be somewhere else). If the rubber bond between the inner and outer elements of the damper are not properly attached, will it still be able to cancel out harmonic vibration? The vibration itself is not extreme, I just think it could be bettered.