When the engines are spinning at high rpms, they get cooking pretty good. Even at an idle, if the cars aren't moving, the engines run so hot that they have to run advanced cooling agents through the system to prevent fatal overheating. What stops the engine from melting when it is at 13,000 rpm?
a 900 hp F1 engine needs to expend about 10,000 Btu/min through its radiators. However, they are not allowed to use anything more exotic than water for a cooling medium.
Running the coolant at as high a temperature as possible will minimize the size of the heat exchanger required, thus reducing weight and drag. To get water to act as a coolant at tempertaures above 212F requires pressurisation of the coolant circuit. A few years ago the F1 guys were running their coolant pressures at extremely high levels to minimize heat exchanger size and to maximize aero efficiency. Enough so, that it became hazardous in the event of an accident. So now they are limited by rules to coolant circuit pressures of less than 30 psig.
