How NASCAR Pre-race and Post-race Inspection Works

Official NASCAR inspection platform
The car of driver Michael McDowell goes through inspection by NASCAR officials before the NASCAR Sprint Cup Best Buy 400 auto race, June 1, 2008, at Dover International Speedway in Dover, Del. See more pictures of NASCAR.
AP Photo/Nick Wass

­It's 10 a.m. on Sunday at Atlanta Motor Speedway, and the NASCAR garage is bustling with activity. On the south end of the long, steel garage building, four NASCAR inspectors roll car after car through the inspection line for one last look at the sleek machines that will soon turn the peaceful morning into five hours of continuous thunder.

The teams roll the cars onto an elevated platform where two of the inspectors will fit a long aluminum template over the nose, roof and trunk of the car. The inspector at the front end slides a small guide between the template and the hood while the other inspector, the one near the rear of the car, does a final check of the rear wing. Meanwhile, another gentleman places a flat piece of aluminum along the side of the car.


­Before the car rolls off the platform, a team member crawls through the window and pounds on the sheet metal from inside using a heavy rubber mallet. Apparently, something doesn't jibe and the inspectors won't release the car until it does.

Finally, the car rolls off the platform and another takes its place. One by one, each competitor will take their turn on same stage. As the cars roll off, they join the starting grid and soon 100,000 fans will cheer for their favorite driver in the Pep Boys 500, the seventh race in NASCAR's Chase for the championship.

Forty-three cars take the track each NASCAR race day. Before a single lap is turned, every car must pass a series of rigorous inspections under the watchful eye of Sprint Cup director of competition John Darby and his team of skilled watchdogs. The same inspectors serve as referees during the race who scrutinize cars as they come off the track. This article will explain both the pre-race and post-race inspection process as well as give some examples of cars that fail to make the grade.

­What happens when a car doesn't pass inspection? Does the winning driver lose his trophy if NASCAR finds something amiss after the race? These answers and more lie ahead. Let's begin with pre-race inspections in the next section.


Out With the Old, In With the Car of Tomorrow

Bill France Sr. founded NASCAR more than 50 years ago with the idea of having a racing series of stock cars -- cars you could actually go down to your local dealership and buy off the showroom floor. Over the years, technical improvements and years of research and development have changed the game, but the original philosophy remained the same. NASCAR rules required teams to field cars that at least resembled cars found in the manufacturer's product line.

­With the inception of NASCAR's car of tomorrow (COT), Sprint Cup cars have taken on a whole new look and lost the fundamental individuality of cars seen in the past. As a result, the inspection process has evolved to accommodate the new cars. NASCAR still wants the cars to be as evenly matched as possible. In years past, competing manufacturers each gave their teams a different vehicle with different specifications for competition. As a result, NASCAR used several different sets of templates or measuring devices to check different areas of the car's body. But problems -- such as uniformity of aerodynamic characteristics -- often caused teams form one manufacturer or another to call for changes in order to level the perceived playing field. The car of tomorrow, in theory, is the same across the board for every competitor. The only difference in each body is the decals used to identify the manufacturer.


The inspection process really starts at the NASCAR Research and Development Center in Concord, N.C. Teams build chassis within the same set of specifications, regardless of manufacturer. Each chassis is measured using a high-tech computer and robotic measuring arm to verify the tolerances or measurements at specific areas. Once NASCAR is satisfied the chassis meets its specifications, tiny radio frequency identification (RFID) chips are placed in discrete locations and an approval sticker, similar to a vehicle identification number (VIN) sticker is placed on the chassis for future scanning.

As you will see in the next section, NASCAR has tightened its grip on the inspection process. Officials continue to crack down on teams that push the gray areas of the rules in an attempt to give every team an equal chance for success. Read the next page to learn how they check each car at the track before every race.


Initial Inspection

The Claw
NASCAR officials inspect Martin Truex Jr.'s car as some of his crew members look on, July 3, 2008, at Daytona International Speedway in Daytona Beach, Fla. The car was impounded.
AP Photo/Chris O'Meara

­Before the throngs of race fans show up at the track, NASCAR officials are busy looking over each entry with a fine-toothed comb. Actually, they use a set of highly technical templates to determine whether the cars are within predetermined specifications.

Now that the car of tomorrow (COT) is used exclusively in NASCAR competition, the inspectors use just one template to inspect the cars at the track. As mentioned earlier in this article, NASCAR formerly used several templates to measure the cars. With the COT, NASCAR uses a single template which is actually 19 individual templates welded together into one large template that fits over the entire car. Known by those close to the industry as "the claw," the large template fits over the car and measures everything at once. Like any car that rolls off an assembly line, each stock car that passes through the inspection station must fit within the tolerances of the template. NASCAR officials check each specific point and look for any discrepancies. If they find that a car is not within the claw's grasp, so to speak, they allow the team to take the car back to the garage area and rework the sheet metal on the body until it fits the template. That doesn't mean the teams don't get punished. NASCAR reserves the right to penalize a team if it finds the car to be out of specification. Those penalties usually don't come down until the following week, after the race. In some instances, NASCAR will impound a car and force the team to use its backup or second car.


NASCAR looks for areas where teams may have manipulated the sheet metal or ride height in order to gain an aerodynamic advantage. The claw template is designed to find those areas. As far as mechanical inspections, officials check the fuel tank, engine and suspension in order to search for any areas where the car may be out of specification. NASCAR rules are very clear regarding engine and fuel tank displacement or size. Suspension settings are no different -- NASCAR determines what's allowed and what is not.

Also new with the COT is the presence of a rear wing. If you've ever watched a Sprint Cup race, you may have noticed all the wings are black despite the bright colors each car adorns. That's because NASCAR doesn't allow teams to paint or place decals on the rear wing. In fact, NASCAR is very strict regarding the wing's height and size. In fact, before every racing weekend, NASCAR issues each team a wing to be used during the race. That doesn't mean that teams don't attempt to manipulate the rear wing on the car. The brackets that hold the wing in place are installed by each team at its own discretion so there's still plenty of room for error regarding wing height.

Restrictor plates -- metal plates placed over the air intake to restrict air flow -- are used only at Talladega and Daytona superspeedways and these are also distributed by NASCAR. Officials actually place the plates on top of the manifold and observe the team as they bolt the carburetor on top of the engine. To date, no team has been accused or found guilty of tampering with a restrictor plate. Doing so would certainly bring with it a severe penalty.

With the initial inspection process complete, teams are cleared to practice and qualify. But the inspection process doesn't stop here. In fact, it's just begun. NASCAR officials still have two days of work ahead, and teams still have plenty of time to monkey around with their cars, if they so choose.

Let's move to race day and find out what goes on before and during the race. This is where you'll see that an inspector's job doesn't end until the last car hauler heads back to the shop.


Pre-race Inspection and Officials During the Race

Post-race inspection
Ryan Newman's race car is pushed into post-race inspection following his win in the 50th running of the Daytona 500 at Daytona International Speedway in Daytona Beach, Fla., Sunday, Feb. 17, 2008.
AP Photo/Paul Kizzle

­After each team qualifies, NASCAR conducts a post-qualifying inspection to look at areas such as the fuel tanks and the suspension. NASCAR teams have engineers that are smart enough to develop shocks that can actually adjust during a qualifying run. At times, cars have been found to be either too low in the front, or too high in the rear. A car that is too low in the front allows for more downforce on the nose of the car. In the turns, this characteristic provides better grip. Cars found to be too high in the rear provide drivers with more rear tire grip. This is a result of the rear wing sticking up higher into the oncoming air. Fuel tanks are always inspected to make sure teams comply with the designated fuel cell capacity. Even an additional gallon of gasoline can be the difference between winning a race and finishing one lap down as a result of running out of fuel. Fuel strategy plays a major role on race day. If you'd like to learn more about NASCAR fuel strategy and a technique called hypermiling, then read this article.

On race morning, teams are once again required to roll through the inspection process. As you read earlier, every team shuffles their car (or cars) through the final pre-race inspection station for one last check of everything. The process isn't quite as­ detailed as the initial inspection; however, officials are still paying careful attention to every detail, especially the rear wing. Inspectors slide gauges between the template and the hood to check tolerances. If the gauge doesn't slide freely, the hood is too high and must be fixed. That's why teams bring rubber mallets to the inspection area.


After the cars pass through the inspection line, they go back to the front of the garage and into the shock station. There, teams charge their shocks with the required amount of pressure. Under the watchful eye of NASCAR inspectors, teams install their shocks and are ready to go.

Now, you may think an inspector's job is done once the cars make it through the inspection lines. It's time to go watch the race, right? That sounds like a pretty good job perk. While they do get to watch the race, it's from the team's pit boxes. That's because an inspector doesn't actually get to rest during the four to six hours of a typical race. On the contrary, inspectors are NASCAR officials first and foremost. That means they have to serve as referees during the race. Each inspector is assigned a driver and it's their responsibility to make sure the teams are adhering to NASCAR rules throughout the entire race. Part of that responsibility is watching closely as crews change tires and fuel the cars during pit stops. For instance, it's the NASCAR officials' job to make sure all the lug nuts are on the wheel studs after each pit stop as well monitoring the actions of the crew members. Officials make judgment calls every single race that can penalize a driver with a time penalty, or worse. It all depends on the severity of the infraction.

­After the race is completed, NASCAR officials still have work to do. It's up to them to conduct the post-race inspection. Typically the top five cars are brought through this final inspection and checked for measurements one more time. It's here where some big-time infractions are often found. Let's go to the next section and learn about this final piece to the inspection puzzle. We'll also shed some light on how penalties can affect a team's position in the point standings.



Post-race Inspection and Penalties

When conducting a post-race inspection, NASCAR investigates several things. First and foremost, inspectors measure the height of the rear wing. NASCAR gives teams the benefit of the doubt during these inspections. In other words, it takes in account race damage as possible reasons for a car not coming in at the mandated measurements. In fact, there's usually a range the car must fall into. Officials measure the height of the rear wing and front splitter from the ground. If the car is outside of the tolerance area, the car is subject to an infraction.

­From time to time, NASCAR randomly selects race engines to run through a dynamometer for inspection purposes. This process happens in Concord at the Research and Development Center. Usually, teams don't sweat these inspections, but on occasion, red flags have been raised. NASCAR is mainly concerned with horsepower output during these dyno inspections.


Every so often, inspectors do find infractions during a post-race inspection. Sometimes these violations are attributed to racing damage while other times, NASCAR deems them as intentional attempts to circumvent the rules. One of the frustrating aspects of the NASCAR rules is the notion of intent. NASCAR must make a judgment and handle each situation according to what it finds. By building the car of tomorrow (COT) and revamping the inspection process, NASCAR was able to change its outlook on infractions and subsequent penalties.

NASCAR typically waits until the Tuesday after race day to issue penalties. And as you read earlier, Hendrick Motorsports learned first hand that NASCAR would be firm when it comes to penalizing teams that are found guilty of breaking the rules with the COT. NASCAR continues to have as close to a no-tolerance policy as it ever has. Penalties are strict and crew chiefs and other team members have lost jobs in the wake of them. In 2007, Michael Waltrip Racing fired the crew chief of the #55 Toyota driven by Waltrip himself after NASCAR found an illegal substance in the fuel system. More recently, Red Bull Racing fired the team members responsible for the illegal sheet metal found on the #83 Toyota driven by Brian Vickers.

Since the COT's launch, the penalties have been very costly, both for the driver who suffers point losses, and the teams which pay fines -- in some cases, up to $150,000.

­For more information about NASCAR and other NASCAR-related topics, follow the links on the next page.


Lots More Information

Related HowStuffWorks Articles

  • Associated Press. "NASCAR's Carl Edwards docked 100 points, plus 10 bonus points for failed inspection after win." March 6, 2008. (Dec. 5, 2008)
  • Aumann, Mark. "Chassis inspection system a state-of-the-art process." May 23, 2008. (Dec. 4, 2008)
  • Coble, Don. "NASCAR officials welcome controversies." The Times-Union. April 10, 2003. (Dec. 6, 2008)
  • Mejia, Diego. "Stewart wins controversial l." Oct. 6, 2008. (Dec. 5, 2008)
  • "Gordon, Johnson Docked 100 points for violations." June 26, 2007. (Dec. 5, 2008)
  • Rodman, David. "Still more to learn about new car after first full year." Dec. 12, 2008. (Dec. 5, 2008)
  • Utter, Jim. "Red Bull fires worker after Vickers' team gets busted." The Charlotte Observer. Oct. 24, 2008. (Dec. 6, 2008)