The thing about the Mustang with the track pack, Ford ABSOLUTELY guarantees the engine when in warranty. No questions asked. In June we had a 2013 Mustang (track pack) blow an engine on the track (4600miles) and Ford covered it. No hassles..
In regards to 15K oil changes, while 15K works, you will keep your engine cleaner in the long run doing oil changes at 7K. This is what my upper end looks like at 42K and 30 track days.
Valve train two weeks ago for my valve adjustment:
and the lower end just this weekend when you are stupid (like me) and drop a shim into the oil pan:
The oil pan before removing residue oil:
