Spent some time going over the different parts. The cylinder heads look strange, but I think Matts right. The threads are all in tact and it doesn't look like metal has actually broken away from it.

Bearings are smooth, they're not the problem, plus there's no debree at all in the crankcase area. All the carnage is on the side and top of the piston.

Using a magnifying glass I can see where small pieces of metal are missing off the top corners of the piston. That's where it had to come from.

Back when I was running the new OS glow plug on this motor I did remove the sensor from the motor. Reinstalled it when I went back to the iginition and played with it's postion when I was running the motor on my test stand setting up the tuned pipe. That was 28 flights ago. So, I must have screwed it up by throwing the timing off, but in my defense it ran so good on the test stand and showed no signs of detonating. It was actually running really well the last couple days and also right before it failed.

I've been running 90 octane ethanol free gas in it since new.