DonahueMSports8

We have a 2300 that has melted the center of the pistons in #2 and 3 cylinders. we run on dirt and it only run 12 laps since new @ 8000 rpm's. so my question is has anyone ever seen this before? and what might have caused this? here is what I know, the timing is at 36 degrees, engine is not lean, 111 track-tec race fuel, any ideas we are slap out!!!!

Thanks