The problem is that you need to balance the flywheel to the engine you are transplanting it to. In theory each flywheel is balanced for its own engine, at least that is what we have been told. Your old one is balanced for the engine it is attached to and the new one for its engine.

Logically if you can match the new flywheel to the old one's balance and install it in the same position as the old one came out then you should be OK. That would mean marking the orientation of the old flywheel on the crank and then bringing it and the new one to a machine shop which can match the new one to the old one and mark the new one with the same position as the old one had been removed at (they will probably drill some holes to remove weight at some locations). Of course there's also the question as to whether the balance should be done with the clutch assembly attached or without it. Doing it without assumes the clutch assembly is neutral...but then it also assumes the torque convertor on the old engine was neutral balanced too.

Or...you could simply bolt the new flywheel and clutch to the old engine and hope for the best, which is what most people would do, but it is not the "correct" way.

If it were mine, I would seriously consider transplanting the engine and tranny and settling for a N/A 300D rather than the turbo...that would eliminate the need to worry about rebalancing the flywheel.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz