Originally Posted by W.I.N. Racing
My guess is they don't like the grooves and trough cut in the OD. The grooves (as noticed in the pic) seem to be carbon collectors. Also noticed in the pic it looks as if there is a sharp edge at the face/OD interface twocents


Could be. I wouldn't run those pistons either since the top edge is already eaten away. Looks like it was too thin and it just got eaten up by the combustion. Either that or the picture makes it look that way.