We all know that race cars tend to be very different from your average family saloon; They have different tires, more powerful engines (obviously!), no need for rear seats or much trunk space. So it won’t be surprising to hear that they even fill your tires with a different gas. You probably fill your tires with air. That’s a mix of oxygen, carbon dioxide, nitrogen, and small amounts of a few other things. Racing car tires are filled with nitrogen only.
Nitrogen expands and contracts at a more even rate compared to standard air. Considering the speeds race cars tend to travel at, any small change in tire pressure will have big effects on both traction and handling, which could easily change the outcome of a race! When races go on for a long time (such as Formula One or Nascar racing), track temperatures can vary considerably, so the consistency of nitrogen pressures can make a big difference.
Why does nitrogen hold its pressure so much better than normal air? To begin with, the air contains small amounts of moisture. The exact amount varies throughout the day depending on weather conditions, and even small amounts will result in significant changes in tire pressure during tire installation during the race, or on the same car but on different days of racing. race. The driver needs to know how the car will handle to get the most out of it, so dry nitrogen is used instead.
Interestingly, nitrogen is also used for similar reasons on airplanes, where it is of paramount importance that tire pressure does not vary too much with different external conditions. An airplane traveling at different altitudes will be surrounded by air at different pressures and temperatures. In fact, the temperature can drop as low as -40°C, so you don’t want any moisture on the tires as it will freeze and cause problems when landing.
Is there any reason you would want to fill your own car’s tires with nitrogen? There are definitely benefits, so it’s up to you to weigh those benefits against the costs and make your decision. The lack of moisture in the nitrogen results in less corrosion on the wheels, and since nitrogen molecules are larger than oxygen molecules, tires will hold their pressure longer. The downside is that you’ll need to empty your tires of air first before filling them with nitrogen, and to maintain the benefits, they’ll always need to be recharged with nitrogen.