Paul,
at the risk to make a complete idiot out of me.
Do I get the part catalog right if I understand, that the rx-7 13b
automatic transmission does have no flex plate, but only a counter wheigt?

http://www.wankel.net/~krwright/cars/rx7/manuals.html

Thomas

No it also has a counter weight. You need both.
BTW Tracy Crook incorrectly calls the flex plate a flywheel.
Mazda calls it something else but the name of the part in the U.S. has
been flex plate for years. The flywheel has the counter weight incorporated.

Here are some pictures to distinguish the difference.