SOOO far anything that has happened to this engine was something I didn't do myself. I can't really blame the machine shop who assembled the heads on the retainer snapping but I just find it odd how all the stuff and assembly work I did is still holding up very well, still tight and hardly worn and twice now work they have done has resulted in some sort of failure. Might be time to check out some other shops.... Well, I figured that the valve was toasted but what about that guide...I guess I won't know fully until I pull er' off but still I will ask...