> After some time pondering this flywheel business over the
   weekend, I'd
    > like to challenge the assertion that switching from manual to
    > automatic flywheel requires a change to the counterweight on  the
    > engine.
    >
    > The flywheel I have has clearly been balanced independant of the the
    > engine.  There are weights welded to the rear face of the flywheel -
    > presumably to allow it to spin true.  I assume that an automatic
    > flywheel would be no different.  Given this, I cannot see how the
    > counterweight -- which is part of the engine assembly -- plays into
    > this.
    >
    > In a similar example, the first step of mounting a redrive is to add
    > the dampener plate to the flywheel.  A dampener plate - I might add -
    > which greatly changes the inertia of the flywheel & shows itself no
    > signs of having been balanced (i.e, no weights added).  I find it
    > difficult to believe that this is somehow different, and does not
    > require a counterweight change, where the flywheel it is bolted to
    > 'does'.
    >
    > So -- am I missing something here?  Happy to be proven wrong, but
   this
    > is not passing the smell test for me right now.
    >
    > (Yes, all of this is my desperate attempt to avoid having to
   fight the
    > e-shaft nut off)
    >
    > Mark
    >
    > No Mark the counter weight is independant from the weight of the
    > flywheel. Once balanced the engine will run fine with no flywheel.
    > Only the counter weight is required. However your options are
   near zero.
    > If you have Tracy's dampener plate you must have a disc with a
   ring gear
    > to bolt it too. The ring gear must be in the right place as well
    > as the mounting surface for the dampener plate.
    >
    > You need to start searching for an automatic transmission flywheel
    > (flex plate) and a rear counter weight. You should then have the
   engine
    > rebalanced with the new counter weight, the auto tx flex plate
   and Tracy's
    > dampener to be totally correct. Many people don't bother and just get
    > the right counter weight. You need to talk to Dave Lemon or John
   at Mazdatrix
    > about the correct counter weight to be used with the high
   compression rotors
    > they put in your engine.
    >
    > There are some light weight flywheels out that that might work
   however.
    >

   Dave tells me I do in fact have a flex-plate.  It is one of the
   earlier 'flat' style ones.  Further, that I can attach a deeper one
   without having to change out counterweights; the engine was assembled
   with automatic counterweights already.

   Based on this, it seems I need only get a newer flex-plate & drive on...

   Mark

That seems to make sense.  If there is a counter weight there, it was an
automatic transmission.  I would think other flex plates would work.