Brakes and Air Density


#1

I worked for many years for a manufacturer of fans and blowere for heating and air conditioning and we had to assist customers in sizing speed and power reqd. At high altitudes the reduced air density reduced heat transfer. Wonder how this affects brake life, disk warpage and the like ?. JRR


#2

Possibly a little. However I think It may have a much greater effect on the power of vacuum assisted brakes at high elevation. ie the higher you go the lesser the difference between atmosphere and your intake vacuum.


#3

At higher altitudes, the lower ambient temperature is more than adequate to offset the very slightly reduced air presure. The cooling effect is a function of temperature difference and, to a very small extent, the conductivity of the air, which varies more with the HUMIDITY than the atmospheric pressure. The worst place for your brakes is Death Valley, Cal., which is below sea level; very dense air, but bone dry and very hot!!


#4

Millions of drivers putting on billions of miles have not noticed any difference.


#5

It’s not an issue on street cars that which more than adequate brake cooling for normal conditions (my brakes work just fine in denver). However, it is a challenge for race cars at high elevations in hot climates. When there was a GP race in Mexico City (about 6000 ft above sea level) the teams all added huge brake ducts to their cars.