I'm burning up a plug per flight on my Tiger Demon and K&B 6.5. I am tuning so the motor is not lean and it lands with the head just barely warm. In fact, the motor is running super. Problem is I am popping a plug per flight on only 15%!!?? A flying buddy at the field gave me a good McCoy and it lasted 1 flight. I am flying 8oz of fuel per flight so the flights are about 6-7 minutes at full blast and around 20K+ RPM (in flight). Is this a compression thing needing shimming of head or do I just stock up on plugs. Pretty soon I am going to wish I threw an electric set up in there if I blow up a $5-6 plug per flight.
Do I go to a cooler plug, hotter plug, add a shim and if so how do I make one and thickness needed. Thanks.
http://www.youtube.com/watch?v=TPnXLDbEO9M