[SF18C]

I know that this may sound unconventional to most and I will not try to persuade anyone to my way of thinking.

A few years ago (okay, it was more like 10) I was detailed as a Personal Security Detachment Driver. One of the training events for this was attendance to the Bill Scott School of Racing for advanced offensive driving techniques. There, we were taught about some of the mechanical aspects hard advanced driving. One of the things we were told to do, and did so several times throughout the training cycles, were to check the pressure of the tires while HOT. Tires heat up during use, hot air expands, expanding air increases the pressure; we all know this. As I was instructed, a tire at its upper limit cold will be “over” inflated after several hours of hard driving. An overinflated tire will react harder on impact and will loss grip when pushed hard. We would log these temps both hot and cold and after changing tires we would be able to correctly fill the cold tires to the correct PSI so they would not be over inflated after abusing them for a few hours! We changed tires 2 or 3 times a day…oh yeah brake pads were usually changed every night!

Now the reality is what is the difference between hot and cold temps on air pressure? Not really enough to effect modern tires used for everyday driving.