It is hard to tell how the cam got 15* advanced, but if it got there with the head installed then yes it is likely that you have some damaged valves and hopefully that's all.

Quick story: When driving my coach through GA my engine had a brief hiccup, then continued to run, but was missing on one cylinder. Drove to a CAT dealer in Macon to have it fixed (have my CAT fixed, get it?).

I had a roller come out in the injection pump, which jammed the IP and stopped the pump with the engine running. It made one complete 720* rev without the pump, the timing gear then seized to the IP shaft and tore the lobe off of the cam so that it could begin to turn normally again, sans one lobe, perfectly in time. This stuff is rare but does happen.

So could your engine have jammed the cam & timing for 345* and then resumed turning? Certainly. I wouldn't bet my life on it, but it could have.

__________________

Gone to the dark side

- Jeff