Leon, I'll have to take a closer look at the valve when I have some time. I took a quick look at the piston and didn't immediately notice any kind of contact mark on the top, but who knows. I'll get into it later. I don't think that it would be a bent valve, as our engines are supposed to be non-interference, but if the valve broke off, somehow, and extended farther down than normal I guess it's a possibility. I would think that if the valve broke off, it would have stayed in the cylinder and caused more damage. Also, it didn't fall out of the head as I was flipping it around.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless