I think I killed it

I was at the track tonight for test and tune, trying out my new cam, first run was great best time and speed, second and third run not to bad. Fourth run it was running like crap, puked of the line, got it back to the trailer and opened the hood, and it was ideling really bad and hit the throttle and I heard it knocking, couldn't hear it over the open headers. I shut it down right away pushed it on the trailer and brought it home. I pulled the valve covers off, everything looks fine with the valve train, but I can see small copper colored flakes of metal in the oil, I am thinking a spun bearing but not sure. I am going to have to perform an autopsy but looking for suggestions on what you think it might be.

Greg