[1turbofocus]

From what I am seeing it looks like some trash went though them , there is very little clearance on the cams and even a hair will do what your seeing , grit of sand , metal from machining

The biggest mistake I see people make when I see this and I have seen it a lot is they do head work , porting , surface etc and dont pull the oil passage plugs out and clean the head throughly and there is 6 plugs to pull out of you cannot clean the head throughly

Tom