This subject keeps coming up from time to time.
I thought we had it put to bed years ago :)

The  p-port valve overlap is of no consequence in a high RPM, high power aircraft
engine just like it was not a problem on the 1991 LeMans winning engine and
the p-port 3 rotor engines now running and winning in the Rolex GT races.
These Le Mans engines had the lowest BSFC every achieved in a rotary.

The stock side port RX8 engine has no overlap for Hc emissions reasons at
idle and low rpm low power typical in automotive use.

Those engines in the Rolex GT RX8 are old 3 rotor engines with p-ports.

P-port engines have won many 24 hour races back in the 1980's.

There are no apex seal wear issues as the p-port area is a very benign part
of the rotary. There is no pressure difference across the apex seals as they
pass over the p-port. The 13B p-port hot exhaust is far far harder on the
apex seals than a much  cooler p-port intake.


The RX8 side exhaust/P-port intake is particularly good combination
as it idles as well as any 13B with side intake and p-port exhaust.

Read:
http://www.rotaryeng.net/fund-of-intake.html
http://www.rotaryeng.net/Welded-steel-p-port.html

BTW what is the valve overlap in a turbine engine?
The rotary comes far closer to a turbine engine in this regard
than any piston engine.

Paul