So, I inquired again to Jack Kane of epi fame (Jack Kane <jkane.epi@gmail.com) who does a lot of gearbox work. He had these comments when I asked if he had any involvement in the nice Mistral rotary engine psru……
Also, it is my understanding that any torsional excitation of a Mazda rotary is LESS harmful than those of ANY piston engines (no reversals). Is this not true, or is the rotary torsional excitation just “of a different sort”?
“Tracy Crook's gearbox, as I understood it, was plagued with reliability issues - a lot of which were related to
the use of that 6-planet Ford C6 gearset, which does not have NEARLY enough capacity to live on a relatively
high-powered engine, and especially one in which the engine torque pulses are not isolated from the gearbox.
And a Wankel is quite a bit worse for torsional excitation than a piston engine, especially an 8-cylinder one.”
Marc (with a Tracy 2.85 RD-1C)