Your concern about torque characteristics is very real with fixed
pitch
props on high
performance airplanes. low end torque is sacrificed with any type of
engine
when it is
timed (ported) for high output at high RPM. I feel that the Wankel is
particularly
sensitive to this effect. With controllable props, this is of
course, a non
issue,
and absolute horsepower rules - Vance J

Vance, I too used to think that Wankels were prone to loss of low end
with enlarging the ports.  After building and porting a couple of
engines, (all 6 port engines which according to net/garage lore are
perfect from the factory),  I don't think this is the case AT ALL.  I
was in a hurry on the last one so I didn't enlarge the ports and it is
so much weaker at 1500 RPM than my last ported one, that it is
ridiculous.

In my experience, the larger the port, the better, even at low RPM.  My
porting isn't all pretty like the pics I see on this list either.  I do
them by hand with my wife's flexible shaft so they are a little uneven
and rough, but I chamfer the edges and they work great.

Hans Conser

 
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