Hello guys, I am in fact not a beginner but I have a beginner question I guess:

What is the maximum length of time we should fly a plane at maximum speed? thinking about the engine during a flight of 10mins for example.

For instance, I have a mustang PTS flying with an OS 46FX, the power is very nice of that engine and I like to fly it at max throttle (even though sometimes I keep it at 95% throttle). The thing is that I feel I am somehow "abusing" of the engine if I fly too long at full throttle..... is there any concern that I burn out the engine or the piston gets overused or damaged if I fly too long the plane at max throttle????? I do not want to damage my engine, therefore I usually fly at mid-stick but I would prefer to fly longer at max throttle...

Thanks!