2004R trans flex plate?

[V-6 Power]

Everywhere I read, people are suggesting to use a heavy flywheel with the 1975-1976 Buick 231 3.8L odd fire engine to get the engine to run smoother. If I were planning on using the 200-4R automatic trans with this engine, is there a particular flex plate that I should use? If yes, does anyone have a part number? Thank you for your support, Tommy.

[ULYCYC]

You would have to use the flexplate that came with the motor. It would take a lot more then a heavy flexplate to get those to run smooth. It should have the correct holes for the 200R4 converter to bolt up to. GM pn# 1255728 is the correct one for that year. If you want heavier you would have to get a custom SFI made to order since none are made for that engine. It's not too popular in the racing circles