Air Dam - A piece of the car body that hangs under the front grill of the race car, very close to the ground. The air dam uses air pressure to force the car down on the ground (called downforce) at the front of the car and to improve handling. NASCAR has rules on the air dam to keep things fair

Air Pressure - Specifically the air pressure of the tires. Changing the air pressure in the tires is a way to alter the setup and handling of a NASCAR race car. Different tires are set to different air pressures to adjust for the conditions of the track. For example, if the race car is tight coming off a corner, a driver might request an increase in air pressure in the right rear tire to "loosen it up."

Apron Synonym: “The Flat” The apron is the asphalt on the bottom of the race track just below the banking marked by a white or yellow line. The apron is primarily there either for cars with issues to get out of the way of traffic to get to pit road, or for cars to speed up coming out of pit road. At most race tracks, drivers may drive onto the apron on the front stretch to make passes, but, advancing position on the apron is ILLEGAL at Daytona, Talladega, and Atlanta (Double Yellow Line).

Banking - The slope of a racetrack specifically at a curve or a corner. The angle of degree of banking refers to the height of a racetrack's slope at the outside edge vs. the inside edge. Steep banking can allow race cars to maintain speed through the turns. A low banking track will require that the cars slow down through the turns. The difference in banking between tracks is yet another challenge for NASCAR drivers and race teams to deal with each week.

Chassis - The shell of the race car itself including the floorboard, interior and roll cage. The chassis is loosely based off of standard manufactured cars. NASCAR has rules that all chassis' must conform to in order to keep the races as even as possible.

Crew Chief -  the head honcho of the race team. They function similarly to a head coach in other sports. A crew chief is responsible for determining the car’s set up, deciding on pit strategy, and getting feedback from the driver on how the car is driving.

Dirty Air - The messed up air created by the lead car. It is generally harder to handle or steer a race car when it's in dirty air. Some race cars will be set up to run good in clean air when in the lead and some will run better in dirty air.

Downforce - The air pressure on the race car that causes it to hold the track of pushes it down on the track giving the car better traction. In order to increase corner speeds, NASCAR racing teams strive to create downforce that increases tire grip.

Drafting - When two or more race cars run closely behind each other, sometimes nearly touching. The front car breaks through the air allowing the car in back to have less air resistance and to gain speed. Often a car will use the draft to gain speed and then use the momentum to pass the car in front of it. This is a major strategy in all races, but especially in restrictor plate NASCAR races.

Drag - This is similar to aerodynamics. Drag is how well a race car travels through the air and how much resistance it offers. NASCAR race teams work to get the lowest drag number possible for higher straightaway speeds.

Fabricator - the person or people who design and build the shell or sheet metal of the race car. Each race car is custom made for a specific type of track or even race.

Firewall - this is a metal plate that sits between the engine area and where the driver sits. It protects the driver from a fire in the case of a wreck. Safety is a major feature in NASCAR race cars and fire is one of the major dangers for drivers during crashes.

Grip - with how well the car sticks to the track. If a driver complains about a lack of grip, it means that the car is unable to stay in one spot and is hard to keep stable. A car that grips well will stay in one line throughout the track, allowing the driver to maximize the speed through the corner.

Groove - Refers to a specific route around a race track. There is often a high groove and a low groove. Teams often tailor the setup of their car for a specific groove.

Happy Hour - the last practice session held before a NASCAR race.

Loose - an undesirable condition of the race car. This is when the car's set up causes the back end of the car to overtake the front end while entering or exiting a turn. NASCAR teams are experts in adjusting the race car quickly during pit stops to make the car tighter or looser depending on the condition of the car. Some cars will get looser as the longer they run without new tires or as the track heats up or cools down.

Pit Road - An area just off the race track where the pit crews service the race cars. NASCAR pit crews are proficient at changing tires, making adjustments, and even fixing major issues with a race car in just a few seconds.

Pole Position - The front position in the start of a race. In NASCAR, the fastest qualifying car gets to start here.

Quarter-Panel: The sheet metal on both sides of the car from the C-post to the rear bumper below the deck lid and above the wheel well.

Restrictor Plate - An aluminum plate designed to reduce the flow of air and fuel into the engine's combustion chamber. This decreases the horsepower and speed of the car and is used on certain NASCAR race tracks to make the races safer (hopefully). It has the negative in that all the cars tend to run the same speed and they tend to bunch up causing massive wrecks in some cases.

Roof Flaps - A key safety feature in NASCAR race cars, the flaps are placed on the roof of the car and pop up when a car is running backwards to keep the car on the ground during wrecks. Prior to roof flaps being a required feature many cars would fly into the air when they spun backwards at high speeds, causing horrible wrecks.

Roll Cage: one of the oldest safety innovations in NASCAR. The roll cage is a series of strong metal pipes throughout the skeleton car that creates a strong “Survival cell” where the driver sits. The goal is to keep the car intact around the driver to prevent injury from the car denting either inwards on the door or from the roof.

Setup - This referes to various adjustments that are made to the race car's suspension for handling at a specific racetrack. It is often changed throughout NASCAR races at pit stops via the track bar or air pressure in order to help the car to handle better through the turns.

Short Track - NASCAR racetracks that are less than one mile long. On the current schedule those are: Bristol Motor Speedway, Dover Motor Speedway, Iowa Speedway, Martinsville Speedway, New Hampshire Motor Speedway, Phoenix Raceway and Richmond Raceway.

Slide Job: (In your best Dale Jr. voice, also referenced in our Lingo Guide!) This is more common in dirt racing but does occur in NASCAR. It is a maneuver where one car uses the low line around the turn and allows their car to slide up in front of the car taking the high line while completing the pass and blocking the car in the high line from crossing over.

Slingshot: A maneuver in which a car following the leader in a draft suddenly steers around it, breaking the vacuum; this can provide an extra burst of speed that allows the second car to take the lead.

Splitter: Runs the entire width of the car at the front and sometimes appears as if it’s touching the ground. What the spoiler does for downforce in the back of the car, the splitter provides downforce to the front. Damage to the splitter can be difficult to overcome because of the important role it plays in the aerodynamics of the car.

Spotter - a driver’s eye in the sky. Spotters are situated typically on the top of the press box to get a bird’s eye view of the entire track, and their job is to alert the driver of their surroundings. With no ability for the driver to turn around in the car, the spotter tells the driver when cars are near them or trying to make a move.

Stage Lengths: Each race is typically comprised of three stages (Stage 1, Stage 2 and the Final Stage; the Coca-Cola 600 has four stages). Each stage has a length before it ends. Only the Final Stage will see a NASCAR Overtime finish.

Superspeedway - A NASCAR racetrack that is more than 2 miles long. These feature more drafting and pack racing. On the current schedule those are Daytona International Speedway and Talladega Superspeedway. Pocono Raceway is also considered a Superspeedway based on its length, although tighter, flatter corners eliminate pack racing.

Sway Bar - a bar that is used to counteract any rolling force the NASCAR race car encounters during turns.

Template - a standard shape that the race car must comply to be within the NASCAR rules. The template closely resembles the shape of the factory car. All cars must pass the template. NASCAR often checks the template before and after races to make sure that a race team did not try to make changes during or just prior to the race.

Tight - This is an undesirable condition of the race car. A NASCAR race car is tight when the front wheels loose grip before the rear wheels loose grip when going through a turn.

Track Bar - Often used to change the handling during a race. This offers a way to "tighten" or "loosen" the race car by adjusting the cars rear role center.

Turns -  pretty self-explanatory word, NASCAR is a bit confusing about what it defines as a turn. For example, most race tracks are “Tri-ovals” or “D-Shaped Ovals” with two big turns at each end and one gentle curve on the frontstretch called the “Dogleg”. While many would look at it and claim there are three turns, NASCAR tracks officially have four turns with the first half of both bends being turns 1 and 3, and the second half of them being turns 2 and 4. 

Victory Lane - the place where the winner of a NASCAR race goes to celebrate after winning the race.

Wave Around: Lapped cars that do not pit during a regular yellow-flag pit cycle are allowed to take a “wave around” past the pace car once the one-to-go signal is given during that caution period. This procedure ensures that lead-lap cars restart at the front of the field. Wave-around cars restart at the rear of the field, but they are placed in front of cars that have received a penalty. 

Wedge - The wedge can be adjusted during a race to slightly change the handling of the car. Adjusting the wedge changes the relationship of the weight of the race car from one corner to another.