Why Does NASCAR Use Nitrogen In Tires?

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NASCAR cars differ from road cars in many aspects and therefore require different components. NASCAR uses nitrogen in tires instead of air for a few reasons, and since we use air for our tires in road cars, we may find it strange that NASCAR uses nitrogen in tires. 

NASCAR uses nitrogen in tires instead of air because it is more stable. While pressure builds in NASCAR tires as they heat up, it does so to a lesser degree with nitrogen. If the tires become overinflated, they may severely damage many components of the car, further explaining the use of nitrogen. 

Below, we will reveal in detail why NASCAR uses nitrogen in tires instead of air. We will also explore how much tire pressure builds in NASCAR cars throughout a race’s duration, and whether we believe it is best for road car tires to use nitrogen instead of normal air. 

Does NASCAR Use Nitrogen In The Cars’ Tires?

NASCAR uses nitrogen in the cars’ tires because it is more stable at higher pressures. Racecar tires are put under a lot of stress, and using nitrogen decreases the risk of overinflated tires. Also, nitrogen has less of an impact on tire wear and tear, which is essential during a 300-500 mile race.

Previous generations of NASCAR cars differed dramatically from their production counterparts. Even in the age of the Next Gen car, which claims to at least resemble their showroom equivalents, they still vary substantially. 

One variance you can’t help but notice includes the tires. Just one glance and you will see that NASCAR’s Goodyear Eagles lack tread, they wear down faster than production line tires, and NASCAR teams do not fill them with air. 

NASCAR Cars Are Science Experiments

If you think back to high school, you may remember taking a class called physical science. Physical science, in short, studied non-living things, like gasses, mass, and chemical compounds, unlike its biological and Earth science counterparts. NASCAR falls into the physical science category. 

Think of NASCAR as one massive physical science experiment. From fuel calculations to aerodynamics, engine building, and even gases used to fill tires, physical science enjoys a dominant presence in NASCAR. 

Instead of using air, NASCAR teams opt to fill their tires with nitrogen. This is because nitrogen expands and contracts more consistently, unlike air. And since track and tire conditions vary throughout a 300 to 500-mile race, nitrogen makes for a better option. 

Nitrogen’s Consistencies Explained

Air’s moisture varies depending on the humidity. This moisture causes inconsistent expansion and contraction. Given the location of most NASCAR races in the southern and southwestern United States during the spring, summer, and early fall, nitrogen’s consistency is more logical. 

As the already hot track surfaces heat up, and as the tires heat up as the drivers go round the track, if NASCAR teams opted for air over nitrogen, they are putting their cars at risk of an unnecessarily high pressure. Nitrogen neutralizes this risk by a substantial margin

Key Points

NASCAR cars use nitrogen in their tires for safety reasons

Nitrogen limits the pressure variations within the tires

This is vital as NASCAR tires are put under immense stress during a race

Why Do Racecars Use Nitrogen In Their Tires?

Racecars use nitrogen in their tires because the nitrogen they use is ‘dry’ and so is free from moisture unlike air. This means there are smaller tire pressure variations as the tires change in temperature, and so this consistency makes the tires safer and more consistent in terms of their pressure.

NASCAR always has a motive behind why they do things a certain way, even if it looks strange to onlookers. For example, you won’t find an air conditioner inside NASCAR cars. Nor do they contain speedometers, or fuel gauges. Sounds odd to us, but perfectly logical to NASCAR. 

NASCAR teams also attach spoilers to their cars, they bump draft often instead of outright passing opponents, and their cars further contain no rear or side view mirrors. Though they do have rearview cameras

Much of the above components are necessary for safety. If NASCAR allowed their drivers to use air conditioning, for example, odds are they would spend green flag laps fiddling with the unit, which would take their focus off the racing. Drivers would also continually check their speedometers and fuel gauges, which further affects focus. 

Nitrogen Tires Are More Strategic

While nitrogen-filled tires are safer for NASCAR cars than air-filled ones, they are also far more logical to use. In NASCAR, teams want to maximize more than just speed to win a race. And by choosing nitrogen over air, they can do just that. 

Since air can cause drastic fluctuations in tire pressure, it could impact fuel economy and tire wear. When drivers travel at high speeds throughout a NASCAR race, their cars are even more prone to these fluctuations depending on the track conditions. 

Air-filled tires would force drivers to pit more often while nitrogen-filled tires help keep the car performing at peak capacity. Since all NASCAR teams do this, however, it does not give anyone a true competitive advantage. However, using nitrogen tires is easier on a NASCAR team’s budget.

Budget Friendliness

Fun Fact

NASCAR teams can spend up to $20,000 on tires for each race

Do the math, and that’s $720,000 per season with 36 points-paying events. With NASCAR looking for ways to keep costs down for its teams, it makes sense to use nitrogen over air if it means prolonging vehicle components. This doesn’t just include saving tires. Since tire pressure remains consistent with nitrogen instead of air, the car’s handling is also better. 

This helps save brakes, decrease the risk of engine overheating, and prevent tire failures. Even with big-time sponsors, it still costs NASCAR teams millions each season to run 10 months’ worth of races, meaning anywhere they can save money, they will.

Key Points

Many racing series use nitrogen in their tires

Dry nitrogen is devoid of moisture, which helps minimize pressure variations

Using nitrogen in the tires helps NASCAR teams save money in the long run through decreased wear and tear

What Pressure Are NASCAR Tires?   

NASCAR minimum tire pressures are around 20 psi for the left front, 22 psi for the left rear, 50 psi for the right front and 46 psi for the right rear. The pressure of NASCAR tires varies from race to race, with the track surface and layout being considered along with the track conditions and temperature.

Depending on where you live, you either embrace cold weather or dread it. But cold weather affects tires in the same way: It often lowers tire pressure. These days, your car probably lets you know when one of your tires has less-than-ideal pressure. 

Even with your dashboard telling you when a tire is low on psi, tire experts tell you to measure your tires with a tire gauge before driving when the weather dips below 32 degrees Fahrenheit. This is because when the temperature drops, tire pressure drops. 

Let’s shift gears to the NASCAR track, where the tires are typically hot. The temperature of your road car’s tires can reach 160-degrees Fahrenheit. But, since NASCAR cars are whipping around the track at 180 miles per hour or faster, they get even hotter, often between 230 and 240 degrees Fahrenheit (110-115 degrees Celsius)

Tire Pressure Explained

Air molecules move fast, and they are always moving. When these fast-moving molecules move within a tire, that’s what causes tire pressure. They push outward when they hit the inside of the tire. As the tires heat up, both through the track heating up and the driver warming the tires just by driving, the molecules move faster, and the pressure increases.

At intermediate tracks like Homestead, the right front tires can build up to 70 psi. However, the right front tire begins at just 47 psi, as 23 pounds of buildup occurs throughout the race.

Key Points

NASCAR tire pressures vary by tire and by track

As temperature increases, so does pressure

NASCAR tires can increase in pressure by up to 23 pounds per square inch (psi) over the course of a race

Should You Use Nitrogen In Your Road Car’s Tires?

You can use nitrogen in your road car’s tires, but it’s not necessary. It won’t hurt your car’s tires, but it is not essential. If you used nitrogen in favor of air, your tires will benefit from slightly steadier pressures and you won’t see such low pressure in the winter months. 

So, if you live somewhere that winter likes to hang around for a while, it may be worth it. But you always need to remember that nitrogen does not always make a difference. Suppose you lose tire pressure through leaks or punctures; nitrogen will not save your tires any better than air in these cases. 

Check Your Tires Regularly 

Even if you chose to drive your road car with nitrogen-filled tires, tire experts agree that you should still check the pressure regularly even if your dashboard does not inform you of major fluctuations in tire pressure. They also tell you to never drive with under or overinflated tires

While doing so seemingly does not hurt your tires, if you decide to pull out of your neighborhood and hit the road, you risk putting unnecessary pressure on them. You can cause rapid heat buildup and strain, which can lead to tire failure. So, keep your tires at optimal pressure

The best way to know if your tires are under the correct psi is to invest in a tire gauge. And whether you decide to fill your tires with nitrogen or air, be sure to check your owner’s manual if you have special inquiries regarding the care of your tires. 

Final Thoughts

NASCAR teams use nitrogen because it’s not as volatile as air. This keeps tire pressures more consistent as the tire temperatures increase over the course of a race. If NASCAR cars used air instead of nitrogen, tire pressure could fluctuate more and cause problems for the cars.