There was a good reason for teams to use grill tape between the Generation 3 and Generation 6 years and it had everything to do with their cars’ aerodynamics. You may have noticed NASCAR teams put tape on the grill of their cars, and you might have wondered why they do it.
NASCAR teams put tape on the grill to optimize a car’s engine performance, speed, and downforce. This was necessary since the car needed grills to keep air flowing into the engine, preventing it from overheating. NASCAR banned grill tape when they revamped aerodynamics in the Next Gen car.
Below, we will fully outline the reason NASCAR teams put tape on the grill and why NASCAR did away with it when they introduced the Next Gen car. We will also explore whether adding grill tape really made a difference, or if it was the product of a placebo effect.
NASCAR teams put tape on the grill to improve the aerodynamics of the cars. Because the grills let air flow into the engine for cooling, they also add some drag to the cars. Teams would therefore put tape over the grills to try to make the car more aerodynamic and so supposedly faster.
NASCAR Cup cars cost hundreds of thousands of dollars to build. And throughout the season, they can cost millions to maintain. For this reason, you may find it odd that, sometimes, items you can buy at your local hardware store like grill tape will go a long way.
However, these simple items only encroach the car after NASCAR and their teams spend millions on research and development. A car’s aerodynamics was the one reason NASCAR teams inserted the grill tape.
To understand the grill tape’s purpose, you must first understand aerodynamics. When you look at the body of a NASCAR car, you will notice that they carry unique shapes. This shape is done for a reason, as car engineers design them this way to achieve what is called aerodynamic grip.
At the rear of the car, you will notice a raised strip. These strips, known as rear spoilers, are an aerodynamic feature intended to keep cars traveling at such high speeds planted on the track. They were also placed under the car’s front end. By spoiling the airflow, hence the name spoiler, it allowed the cars to travel even faster with less risk of going airborne.
When the Generation 3 car launched in 1981, NASCAR cars became less like stock cars given their sloped windows and rounded corners. Both features improved the car’s aerodynamics. They also added larger fairings to the front and rear bumpers, and sides of the cars.
These made the cars sit lower to where they nearly touched the track. When you look at photos of the Generation 1 and 2 cars compared to Generations 3 through 6, you will notice how much lower the latter cars sit.
These fairings, also called valences, were interchangeable depending on the track. However, there was one major issue: The grills all had openings. The purpose behind these openings was to keep the engine cool. But the unfortunate side effect came at the expense of speed and aerodynamics.
So to keep the speed and aerodynamics running strong, NASCAR teams partially covered the openings with grill tape during races. When cars qualified, teams completely covered the grills since their cars only spent a few laps on the track.
NASCAR teams no longer add tape to the car’s grill, as it has been banned. When NASCAR released the Next Gen car in 2022, they revamped the aerodynamics to allow for better downforce. Openings in the hood allow air to flow over the car’s roof, which keeps it more firmly planted on the track.
And as with all updated rules in NASCAR, they also added more specifications when it came to grill tape. On April 3rd, 2022, Kyle Busch and his team were penalized for adding grill tape. However, they were aware of the rule, having intended to add tape to the brake duct instead of the grill.
The incident occurred at the Richmond Raceway, where NASCAR black flagged Busch on lap 345 for the infraction. Busch’s crew chief was aware of the mistake but did not correct it because he felt the tape would not stick.
The delayed penalty came because NASCAR needed time to review Busch’s pit stops to ensure the team put the tape there. Sometimes, grills can catch unwanted debris, which is not a punishable offense by NASCAR, and they had to rule out this possibility when reviewing Busch.
Since NASCAR penalized Busch for the incident, you may be asking whether they banned grill tape outright or if Busch’s team just put too much tape onto the grill. The answer is that with the addition of the hood vents, NASCAR has since banned the use of grill tape.
Busch was running in sixth place when NASCAR summoned him to the pits. After losing a lap, he was unable to win a lucky dog or race his way back onto the lead lap, and he ended up finishing in ninth.
NASCAR is always making adjustments to its rules, especially as they get a better feel for their current generation of cars.
You saw this occur with the Car of Tomorrow (CoT) when they did away with the cars’ wings in favor of the familiar rear spoiler. This occurred in 2010, 3 seasons before the Generation 6 car debuted.
If NASCAR starts to have issues with the vented hoods that causes them to make changes to the Next Gen car, expect the grill tape to return. However, if the hoods prove to be popular and simultaneously keep the cars better planted, do not expect NASCAR to return to using grill tape.
Grill tape is nothing more than a cost-effective way of modifying a machine that costs hundreds of thousands of dollars to build. Since grill tape is so simple, some may cry placebo effect and claim it’s just a belief and not a proven tactic to keep previous generations of NASCAR cars performing optimally. But in 2016, NASCAR’s YouTube channel interviewed expert Chris Rice on the subject.
When you drive road cars, you will see your gauge that holds a C on the far left and an H on the far right. Ideally, you want the needle to stay in the middle to keep the car running at optimal temperatures.
For NASCAR cars, there are only gauges that tell teams how hot the car is. Rice stated that by adding grill tape, they are optimizing motor temperature, meaning NASCAR teams want a constant temperature in the car during the race, between 230 and 240 degrees.
The 230 to 240-degree temperature allowed the cars’ engines to race fully optimized. However, you may have noticed that at some events, teams used less tape.
Weather plays an important role in NASCAR. In the case of grill tape, teams pay attention to the wind tunnel. Depending on the wind tunnel, teams may place tape only on the left side, or they may completely cover the bottom half of the car with grill tape.
When they placed tape on the left side of the car, they dubbed it maximizing side force. This often occurred at tracks where the weather was cooler, such as during the spring race at Atlanta.
Grill tape was used by NASCAR teams to maximize the aerodynamics of the cars. With the advent of the Next Gen car, things changed, given the vents at the top of the hoods. Grill tape may return in the future, but only if NASCAR does away with the vented hoods.
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