340 Static Compression Numbers and Test Procedure
The weight went on the flexplate in the later Magnums ...... Early Magnums and LA's had the weights on the TC from the factory... as I understand it.
People will switch to an external balance flexplate (like the B&M types) and a neutral balance TC for convenience in getting a variety of TC's.
And yes.... we really don't know what is inside. YR, do you happen to have weight specs on those pistons in this engine? TRW L 2322, probably also the same pinston and number under SpeedPro. If so, I can double check against stock 340 piston weights.