FYI...
Some engines, especially the Merlin in certain applications, could be run at full power until the fuel ran out without overheating.
The magical supply arguement only holds water with respect to nitrous or water injection, boosted engines would run til you pulled the throttle back or the engine quit.
Strip
if i recall, aircraft such as the p51, p38, p47, had a "false" throttle stop...for lack of a better word. when the pilot got into trouble, he "forced" the throttle(s) through this "false" stop, thus increasing his manifold pressure, boost, and i think possibly rpm.
this is what limited the time on these engines. they would overheat, or self destruct.
again, i'm not sure, but one of the mustang drivers that was in our r/c club(Bob Emme, passed last summer) said that using this required the removal of the engine when they got back to base.