I think I cooked my evo. .46 today I was running 2 of them in on a Defiant when the rear engine started knocking and quit.I leaned it out but backed it back down I thought was enough,it now has no compression.........I took it apart and it looks new but no compression.Would a few seconds lean cook it?I guess I need a new sleeve and piston.Both engines I bought at a swap meet as new and they where new as far as I could tell.