[Supras] Chrome moly flywheel

[berniek at technicaldevelop.com]

Brian:

    They are made, and I have one in my '91T which is still going 
together (too slowly).  I don't know if I have the receipt or not, but I 
do know it was Japanese.  The starter pinion teeth and friction surface 
are integral with the flywheel.  I checked static balance of it by 
making a shaft to fit the ID of a standard 6203 ball bearing.  The 
bearing OD was just a few thou less than the flywheel center hole, so I 
was able to use shim stock to lightly press fit the bearing outer race 
into the flywheel.  I put the shaft, with the bearing and flywheel in a 
vise, and found that the flywheel did not have a heavy spot (I balance 
motorcycle tires the same way).  Bolting on the Exedy clutch I bought 
changed that picture completely.  At that point I took the assembly to a 
dynamic balancing shop. 

    A Google search on "chrome moly flywheel" comes up with many 
choices.  I understand from the very competent mechanic who surfaced my 
head and block, and who build race engines that it is a much better 
choice than aluminum.  I did not ask why.  I had Hays aluminum flywheels 
in the past for American cars and they always required balancing.  They 
original came with bronze facings, riveted on, which wore the disc out 
quickly.  I got a steel replacement insert, installed it, and there were 
no more problems.  It may be that in racing use, the bolts or dowel 
holes elongate or become loose quickly.

    Bernie