I don't recall Mazdatrix using RX8 rotors. Do you recall the date
of the message. RX8 rotors are not considered desirable in racing
engines as far as I know. Last I heard they had problems with cracking.
What seems to be the hot tip is 3D NC mill lightened 2nd gen
rotors from Racing Beat.

Paul Lamar ...No rotor no motor.

Hi Paul,
we must have discussed it but I have forgotten.
Was the idle acceptable with the PP that you had on the dyno at
Mazdatrix?
BR, Dave McC

For an aircraft engine I would say it was acceptable.
That is a very subjective thing. All of the rotaries
miss at idle. The side exhaust port RX8 is by far the best
in this regard and the p-port is the worst.
Mazda rates them on the number of misses per minute.
A p-port has to run a bit richer (1.3 L/Hr verses 1 L/Hr)
at 720 RPM or it won't even run for the same ten misses per
minute. At 720 RPM it is firing 1440 times a minute
or twice per revolution. See the attached chart.

BTW people find 1800 engine RPM idle in the rotary aircraft
engine perfectively acceptable because of the 2.85:1 gear
box ratio. 1800 engine RPM is 613 prop RPM. Heck my O-470 won't
even run at 613 prop RPM. I am lucky to see anything
under 800 prop RPM. Tracy got his RX8 engine to idle down
to about 700 engine RPM by further R&D on the rubber PSRU coupling.
You can almost count the prop blades at 245 prop RPM.

Paul Lamar ...No rotor no motor.

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