The object value based on the percentage of a 1000lb bomb to destroy the object. Has nothing to do with reality, and everything to do with what Hitech thinks is a good value for game flow. Also Hitech has answered about WEP, the value expressed in the specific aircraft manual. And those tend to be about the usable operational period of the engine before a swap out. 110 hours was the benchmark time between swap out for many allied engines in combat zones the manufacturer had to meet.
The R2800 was tested for 8 hours at WEP and found to not have any problems. Merlins were found to show micro fracturing on components after being run at WEP for about 200hrs if I'm not mistaken. Combat engines had to be tough. The rules in the manual were to help get operational time out of the engine, not immutable red lines or the engine would die a catastrophic death taking the pilot with it. With exception to the 163.
About the only thing in this wish you may have a chance to gain a change, will be airframe toughness to damage.