Excellent points, all.   I agree.  Esp. #3!  There is some legitimate

question

whether air cooling will work for a 150+hp Wankel.  My engineering feel

is that

it would be well within the range of air cooling, based on the relatively
modest fin
area on a Porsche 911 head.   These heads are used up into the one
hundred hp per head range with air cooling (and a healthy dose of oil
cooling, too).   By the time Porsche got into the 1000+ hp range for the
6 cyl motors they wound up needing water cooled heads.  Using this
as a benchmark, I'd bet that aircooling would be fine, if properly

engineered

up to about 300 hp or more with a Wankel.   Remember that I am
postulating a 4 liter or so motor, maybe 1.5-2X the width of the 13B, so
more area would be available for fins.

Bill
Long EZ builder & pilot
BSME, MSME

Just a thought, but, a cylinder gets a cold shot of air to the whole inside
on every intake stroke.  In the rotary you get a cold(er) side and a hot
side.  The down wind side of the plugs never sees the cold intake charge so
never gets the cooling.  This would have to be a point of concentration for
air cooling.
Mike

Mike McGee, RV-4 N996RV, O320-E2G, Aurora, OR

 
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