> Total Powerplant        414  (Al's all up weight for a NA 20B)

Thanks Al, Good data. Interestingly the LISTED weight for 
a O or IO 540 is 400 pounds. That weight was on the Lycoming web site. 
I am sure that is "dry" and without accessories. The listed weight 
varies +or- about 5 pounds depending on model. That is for a 260 HP
 or less, engine. Al if you were to run a 2.85 : 1 redrive your dyno
 runs NA extrapolate to 300 HP at 6000 RPM. That is not a stressful RPM 
for a rotary. That works out to less than 2200 prop RPM. I am sure a 
comparable IO-540 or 560 (to get that 300 HP) will weigh in at well over 
your 414 pounds.
 If there was ever a better argument for aluminum side plates with the 
steel wear surfaces I haven't seen it! On our 20B's the side and intermediate 
housings in aluminum would be a HUGE weight savings. If Paul's numbers are 
right, (and I have no reason to believe otherwise), a 20B would be around 
100 pounds lighter! That engine would have the best HP/LB of just about 
any internal intermittent combustion engine suitable for aircraft. 
The turbines would still have us on weight, but would have much higher 
fuel consumption.
Bill Jepson

 
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