[F22-Raptor-2006]

nah it's possible, I notice a lot of people changing power and stuff whilst dogfighting. I always use full partly because i'm on keyboard and not joystick. The Spitfire will overheat just like other planes, but because of the automatic system it cools better and more efficiently than manual cooling! Quite a lot of the time you see the radiator completely open. Flying at fast speed also keeps it cool but they still do overheat as I have seen during Air Races after around 5 mins it will start overheating unless you keep it at quite good speed!

I don't think you can make radiator control Manual so with the Spitfire MkIX that 7 minute is inaccurate it would actually be shorter because the radiator automatically opens.