I'm sure I missed this somewhere, but does anyone have
realistic engine life numbers for a traditional
peripheral ported 13B 4 port running in it's
prescribed powerband with regard to aircraft? Thanks!

We have no idea. Nobody has ever worn a rotary engine out. As long as
the cooling and oil system work, life is projected to be 3000 hours or
more based on apex seal wear. Ceramic apex seals have a projected life
of 20,000 hours. P-porting will change that little or not at all.

Does spring strength have any impact on this at all? It would see as though
the center of the seal would want to push out into the port, affecting its
lifetime (as it would wear a bit each time it was pushed back in by the tail
end of the port). A thin bridge across the port would solve this but if it's a
non-issue it's not worth discussing.

Regards,
Chad

I would not run the three piece apex seals as they are far less stiff than a two piece
seal. If so there should be immeasurable bending of the seal into the P-port caused
by the apex seal springs or anything else for that matter at only 7500 RPM.
The P-port intakes are exactly the same as the P-port exhaust ports. Every
Mazda rotary up to the RX8 engine has had P-port exhaust ports.

If the P-ports are causing more wear on the apex seals the side port RX8 engine 
should last 6000 hours.

Paul Lamar
 
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