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How Much Downforce Do NASCAR Cars Produce?

Total downforce requires the sum of two types of downforce, known as mechanical and aerodynamic downforce. But there is even more to the equation than just a simple sum. When figuring out how much downforce NASCAR cars produce, we need to look at a few factors.

The amount of downforce NASCAR cars produce varies, but it’s likely between 3,500 to 5,000 lbs of total downforce. The mechanical downforce is produced by the car, driver, and fuel, while the aerodynamic downforce varies between different tracks, cars, and setups.

Below, we will outline what downforce is and why it is so crucial to the speed of a NASCAR car. We will also discuss how much downforce the Generation 6 and Next Gen cars produce, and we will also touch on whether NASCAR cars produce different amounts of downforce at different tracks. 

What Is Downforce?

Downforce, in very basic terms, is when gravity and differences in air pressure work in tandem to increase a vehicle’s stability by effectively pushing the car into the track. In NASCAR, it amounts to how the air around a vehicle keeps it planted down firmly onto the track surface itself.

In theory, the better the downforce, the lesser the chance a car has of going airborne if it is clipped or turned backward. Downforce is also needed to increase tire grip, which further allows NASCAR cars to race at such high speeds through corners. 

The Opposite Of Airplanes

Downforce is also used in aeronautics. But as you may have guessed, the amount of downforce in airplanes must be considerably different than those in NASCAR cars. This is because planes must go airborne to reach their intended destination. That’s why it’s called lift when we’re dealing with flying, and so downforce can be thought of as negative lift.

How Much Downforce Do NASCARs Make?

NASCAR cars can make upwards of 3,500 lbs of downforce, with a large part of it being mechanical downforce rather than aerodynamic. NASCARs make different levels of downforce with each distinct generation of the car, in addition to variations depending on the specific track and traffic conditions. 

When you consider how much downforce NASCARs make, you need to first realize that downforce varies with each generation of car. For example, the Next Gen car’s downforce is quite different from that of its Generation 6 predecessor. It also depends on the track since all NASCAR tracks require different car setups. 

It is also important to realize that there are two types of downforce in NASCAR: aerodynamic and mechanical. Mechanical downforce plants the tires to the track via the car’s weight, while aerodynamic downforce still plants the tires onto the track, but it does so via air flowing over the car. 

The downforce in a NASCAR car is the sum of aerodynamic and mechanical downforce. Both types of downforce are used during a race, and while they work in tandem, they also hold stark differences. 

Difference Between Mechanical And Aerodynamic Downforce

Mechanical downforce, no matter the situation, remains constant. The Generation 6 car had, on average, 3,500 lb (1,591 kg) of mechanical downforce

Aerodynamic downforce changes every time air flowing over the car changes. It also increases with speed. So, when a car’s speed increases, so does aerodynamic downforce. When the Generation 6 car raced at 132.5 mph (213 kph), it produced roughly 1,000 lbs (454.5 kg) of downforce. But at 187.5 mph (302 kph), aerodynamic downforce increased to 2,000 lbs (909 kg). 

There are also percentage ratios in grip between aerodynamic downforce and mechanical downforce. For example, for a car traveling at 132.5 mph, aerodynamic downforce was responsible for 22.2% of the total downforce. Traveling at 187.5 mph, aerodynamic downforce then becomes responsible for 36.3%. 

Traffic Jam

One takeaway is that NASCAR cars in Generation 6 and later in the Next Gen would see the type of downforce changing based on how much traffic surrounded them plus the speed they were traveling at. So, a car’s aerodynamic downforce decreases when they try to pass a car in front of them. 

This is because cars give off a wake of turbulent air, much like the wake behind a boat. This ‘dirty air’ isn’t as good at producing downforce as ‘clean’ air would be, so the trailing car can’t produce as much downforce. However, this effect is useful for slipstreaming, as reduced downforce equals reduced drag which, when on the straights, means higher speeds.

Do NASCAR Cars Produce The Same Downforce At Every Track?

NASCAR cars do not produce the same downforce at every track. It varies based on track layout and all potential situations that could occur on those tracks. While the car’s weight and therefore mechanical downforce might stay the same, the level of aerodynamic downforce will vary.

KEY POINTS

• NASCAR cars produce roughly 3,500-5,000 lbs of downforce

• This is made up of both mechanical and aerodynamic downforce

• The exact numbers vary by track and situation

• NASCAR cars usually produce more downforce the faster they go

Do Next Gen NASCAR Cars Make Less Downforce?

Whether the NASCAR Next Gen cars make less downforce than the Gen 6 cars depends on the track and the situation. The cars have smaller 4-inch spoilers on most tracks, which does produce less downforce, but changes were made to this spoiler and the splitters that boosted downforce.

The Next Gen NASCAR car features many changes from its Generation 6 counterpart. They carry new chassis, independent rear suspensions, a new five-speed sequential manual transmission, aluminum tires, plus sleeker bodies that better resemble what you would find in a showroom. 

One of NASCAR’s goals regarding the Next Gen cars was for races to be closer, not necessarily faster. Another goal was to better keep these cars planted onto the track surface. To do this, they needed to drastically improve the cars’ aerodynamics and downforce, something they had strived to accomplish for years, starting with the Generation 3 car when they added larger spoilers. 

1,000 Pounds (454 Kilograms) More Downforce 

NASCAR driver Bubba Wallace has stated that the changes to the spoiler and splitters created about 1,000 lb (454 kg) more downforce versus the Gen 6 cars. NASCAR strived to improve the cars’ overall aerodynamics packages with the new splitters and spoilers, allowing for more stability. This is especially apparent on road courses. The new packages would allow for closer racing, too. 

But with more downforce comes more wear on the engines, so NASCAR’s older 550 horsepower engines that they used for most track layouts were not going to cut it. Instead, they went with engines that targeted 670 horsepower. That is because to maintain their speeds with the downforce, engines with 100 or so more horses were necessary. 

How Many G’s Do NASCAR Drivers Experience?

NASCAR drivers experience around 3 G’s of force when they’re racing. The amount of G-forces NASCAR drivers are exposed to will vary between the tracks and even between corners. Usually, the higher the cornering speeds, the higher the G-forces the drivers will feel.

G’s, or G-forces, are something that all NASCAR drivers need to deal with when they are racing at such high speeds. If a NASCAR driver weighs 180 lbs (82 kg), three G’s means that they would feel as though they weigh 540 lbs (245 kg). This is physically exhausting over long periods of time, and the higher the downforce levels, the faster the cornering speeds, and the more G-forces drivers feel.

G’s And Side Effects

NASCAR drivers race for three to five hours at a time, with the only real breaks coming during caution flags, which can vary during an event. So, they are constantly experiencing repeated G’s, which can lead to side effects like dizziness. They can also cause drivers to experience blurred vision and even disorientation. 

None of this is good for the drivers, but it can be outright deadly, with 40 of them driving around a track at high speeds. This is one reason NASCAR drivers must have sound fitness and nutrition programs. 

Final Thoughts

NASCAR cars produce anywhere from 3,500-5,000 lbs of downforce. This number is made up of the combination of both mechanical and aerodynamic downforce, and it will vary by track and by car setup. Usually, the faster the cars go, the more downforce they will produce.