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Kevin,
Yep! there's a lot of truth to what you say about the Ford units- but who knows what abuse their getting.
There is a lot of discussion on the other site with PL supporting the Ford units, a lot of outrageous HP numbers quoted, but Tracy knows the score, as do a lot of others.
The Bell helicopter planetary is being discussed with possibilities for higher HP , the Mistral is just great - but expensive!
I think Tracy suggests up to 250 hp for his unit and the Mistral suggests 300 hp limit. These limits are for a reason and that's to keep in under the failure point for a reasonable life expectancy.
I have no doubt the dodge is a bit better (maybe a lot better) but it has to be fitted to a PSRU fairly easily and has to be the right ratio - 3:1 isn't the right ratio for most people, also most people aren't machinists.
The bottom line is that I haven't seen one perfect planetary set-up for a PSRU yet - we live in hope !
BTW the Ford unit is well and truly good enough for the single rotary, which I'm hoping to complete one day.
George ( down under)
I attended the 782 meeting tonight. Ken Welter talked of his rotary powered Coot experiences. at some point I realized that he wasn't just some hp nut with his nitrous powered 13B (putting out 300hp to get up on step, gross weight up to 3200lbs). with his machinist profession, racing experience, gutsy experimenting, and many stories of surviving potentially lethal situations his opinions are a little more weighty than "I read on the internet that....". another member ran a machine shop that produces all the geared parts for Boeing airliners. he impressed the fact that many experimental failures are with geared redrives, because of the lack of tolerances they run under, unlike belt and pulley systems, that any failure usually becomes catastrophic. Ken talked about a friend who is a top authority on transmissions and his love of ford t-6 gear systems, because they keep him well employed. he said this friend proceeded to show him a 55 gallon barrel of broken parts, not a Chevy or dodge part in there, all ford. ken is working on building a redrive for his Coot from a dodge planetary gear system, 5 pawl, that would produce a 3.12 reduction. his current belt system is at it's size limit and he hopes to reduce the drive ratio he currently has. I wondered if Tracy had heard of any of this, or was looking at the dodge 3.12 ratio drive. I'm not taking sides, just repeating what I heard. I will note, too, that ken wasn't bashing anyone, just relating his experiences. he has 2300 hrs behind Mazda engines in his Coot, using up at least 3 engines and 2 Ross units. he currently has a belt redrive he designed. that upper wheel must be 12" dia! kevin
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