Dave,

 Since you're trolling for ideas, I thought I would run this "solution" by
 you and see what you think.

 Comparing the 20B flex plate to a picture on the Mazdatrix web site, it
 appears that the 20B auto flex plate is identical to the Renesis flex
plate.
  (This is important as we'll need a supply of these for all the others to
 use.)  The outer dimensions (ring gear) and offset from eccentric shaft
 flange to outer face of the ring gear of the 20B flex plate is the same as
 the 13B plate I removed from my 20B today.  The Renesis/20B plate has a
more
 gradual dish shape than the 13B, and is thicker too.  Since I had a spare
 20B flex plate and a spare 13B flex plate, I took a few quick
measurements,
 and it looks like the 13B flex plate could be made to nest down inside the
 20B plate by removing the 13B's ring gear.  That would allow for the two
 plates to be bolted together (no welding required) using the four 20B
outer
 bolt holes along with the six crank bolts in the center.  That's ten (10)
 bolts holding the two plates together.  Then the redrive adapter plate
could
 be attached using the original four bolts in the 13B plate.  This would
 leave the RD2-C aluminum adapter plate offset by the thickness of the 20B
 flex plate (.090"), and would result in a much stronger flex plate.  (We
 could possibly leave out the big flat washers under Tracy's adapter plate
to
 get the adapter plate back to its original location on the psru input
shaft.
  I calculate this flex plate assembly would increase the FWF weight by
about
 4 lbs.

 Mark S. in TX



MarkThis is i was  recommend to use the RX-8 flexplate with a bolt in plate
to received the Tracy damperSee sketch of using 4130 plate instead of
aluminumLike you said on my point of view it will be the best part
availability for everyone


Jean Prudhomme

Jean,

I like your design.  In fact, my design is a modification of yours.  While
yours ought to do the job, I would still worry about cracks around the six
bolt holes on high power applications like mine and David's.  My design
doubles up the support around the eccentric bolt area while accomplishing
what your square plate does.  I think that your design should work fine for
the lower power applications.

Mark