[strother]

I'm going to listen to it more closely this morning, maybe even try digitally recording the sound to post here. I'm not sure that it can be described as pinging -- that makes me think of a slightly higher frequency sound. This sound is a little deeper, kind of garbled. It could very well be pinging, but I don't know....

The sound does go away after a certain RPM. I'd guess that once I get to 3000 or 3500 it goes away. And it only does it under heavy load, not every time I'm in that RPM range.

I can't believe that it would be a broken head stud, given all of the maintenance done on the engine -- they did a compression test, everything was OK. Adjusted the valves and whatnot... I'd like to think they'd have checked for broken head studs.