Paul There is the Mercedes coupler i talked to you before ,they have
  several models on EBAY and very cheap,you can design the shaft
without
  spline but only an adapted flange cup to meet the coupler and the
flexwheel
  as safety in case the rubber fail.I do have an idea of the shaft
design with
  this Mercedes coupler.Ths one is for the 550 model
http://cgi.ebay.com/**

ebaymotors/Mercedes-W116-**450SE-W124-300D-T-300TD-T-**Flex-Disc-Kit-_**




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  http://tinyurl.com/3fhm24k


  Jean Prudhomme

  Does anyone have dimensions for this type of coupler?  I interested
in the
  OD and the thickness in particular.

  Randy

 used to use own a few bmw 2002's back in the day.  These were used
as a flexible coupling between
the driveshaft and the output flange on the transmission (called Guibo
joints).  Having broken a few
and then needed to call a tow truck, I'd never use one on my airplane.

half of the bolts were on the output flange, half on the driveshaft.
When the coupling came apart
it was usually spectacular.

Am I missing something-- are you gents suggesting using the flex disc
in another manner?
William Mason   Yes i know on the car you do have lot of bending action and twisting but
it have one model which
have a steel cage and all bolting are lineup to the same circonference so
if it fail it keep turning
the shaft ,we can use a strongger one similar to the Mercedes 500 and
built a similar cage and will
be stronger and will keep the sungear shaft driven in case it fail.The
steel cage bolted to the
flexwheelIt worth to make one and test it.There is the picture of the one
i am talking and the 500
Mercedes which i am sure is more stronger then the one you had on your
car.

Jean Prudhomme



Hi, remember most oem couplers are used behind the gearbox and see about
3X engine torque in first gear.  If you use a coupler that is sized too big
it will be too stiff and might not help at all.  Unlike most of the rubber
doughnut, the SGFs are reinforced with tire cord.  Most are just rubber
with bonded in bushings.  I designed a Holset type coupling for a rpv
diesel project and told my friend to use the softest rubber rods he could
get from McM. He put hard urethane rods in.  It did not work at all.

Murry I Rozansky