To all with questions about the coupling design, I found a read of Tracy's
site with regard to the PSRU design philosophy to be informative. The flex
plate appears suspect especially in higher HP applications. It appears the
drive rubbers may not be the problem. It comes back to light load on the gears
allows chatter. Less throttle on landing to load the gears from the prop is
the answer. Some type microphone on the side or screwed into the gear case to
pick up the chatter before it becomes damaging may be a solution.

With regard to the possible source of the 2.85 gears, Ford had a wide ratio
kit for the AOD/E4OD with this ratio in the FRPP catalogue a few years ago.


Dale Davies