flyrotary@lancaironline.net Mailing List Archive

Kelly,

I don’t know what could be different about the combustion process itself between a piston or rotary engine.

As you stated, the plugs see a larger number of thermal cycles in the rotary engine. This is mentioned on my web page on SAG as a possible contributor to the spark plug change with age. The fact that Tracy saw a reversal of the tendency for SAG to occur after an extended number of hours on his RX8 iridium plugs is at odds with what I thought might be happening, though. Always more questions than answers.

Steve Boese

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Kelly Troyer
Sent: Wednesday, January 05, 2011 2:31 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: GM Coil Comparison

Steve,

What is it about the Rotary combustion process that is different from

a typical piston A/C engine (although air cooled) running on leaded fuel ??

If spark plug temps are a major factor I would think the A/C piston

plugs would be running hotter..........Perhaps it is the duty cycle of Rotary

(13B) plugs which are tasked to many more times the firing events of a

A/C engine plugs to develop equivalent power........??

Kelly Troyer
"DYKE DELTA JD2" (Eventually)

"13B ROTARY"_ Engine
"RWS"_RD1C/EC2/EM2
"MISTRAL"_Backplate/Oil Manifold

"TURBONETICS"_TO4E50 Turbo