Heat should be a factor of engines and other parts in this game. Heat is generated by fires, engines, friction and explosions. Engines can stall and their fuel intake will freeze up if they get too cold, or could start leaking or weakening if they're too hot. Since

The WWII engine that's "Less powerful than the turboprop" should be way less fuel efficient, generate more vibrations and heat, but can be pushed a lot harder. Over throttling the engines would result in higher risks, but higher speed output.

Over Throttling (Couldn't find a new name) would be a concept of pressing Ctrl and Shift at the same time, doing this will create a red bar to the right of your throttle bar. When your engines are over throttling, you're pushing excess fuel into them beyond their capabilities. This can result in fires, explosions, but most importantly, more heat generation and thrust. Propeller engines will cause dangerous vibrations when over throttled.

-Notes-

Overthrottling has no definite outcome, it could be good or bad
Overthrottling takes up much more fuel without a proportional output
Jet engines will generate less heat at higher altitude, because they have less air.
An automatic overthrottling boost when your plane's body is being torqued by hard turning or maneuvers so you don't lose your speed.