[jrvariel48]

Originally Posted by drolston

Stick your hand out the window at 30 mph and you feel the wind drag. Do that at 60 and the drag is no twice as much, it is four times as much, because wind resistance is a function of the square of velocity. So the horsepower required to push that car through the air goes up rapidly with speed. An with the generation of horsepower comes the generation of heat.



At 60, air flow through the radiator is not the problem, it is the cooling capacity of the radiator. Need more frontal area, more fin area, good contact between fins and tubes, clean radiator interior.


I had the both problems, overheating in traffic and at highway speeds. A cute little aluminum radiator rated for 500 horsepower (a lie) would not do the job, but a good clean stock truck radiator finally solved the overheating issues.

Thank you drolston for an excellent explanation!!