Think of the imbalance like freshly mounted tires. Before the weights are attached theres an imbalance. The weights correct that. Same with the push rod engines. The rotating assembly isn't perfectly balanced. So the flywheel/flex plate and dampner have extra weight to offset the imbalance.RockAuto says this?
https://www.rockauto.com/en/moreinfo.php?pk=65756&cc=1134133&jsn=1005
Not many can go out and count teeth on their flex plate. I should have looked at mine closer, i was back home, and i did a manual swap a few years ago.
Idk what an "imbalance" is, as far as this convo goes. Can't help ya there....