NASCAR Glossary
Aeropush
When following another vehicle closely, the airflow off the lead vehicle does not travel across the following one(s) in a normal manner. Therefore, downforce on the front of the trailing vehicle(s) is decreased and it does not turn in the corners as well, resulting in an "aero push." This condition is more apparent on the exit of the turns.
Aerodynamics
Refers to the way air flows over the surfaces of a race car, over and under the body or through the engine and radiator. It also includes the wake of turbulent air left behind a car as it travels.
Aerodynamic Drag
A number that is a coefficient of several factors that indicates how well a race vehicle will travel through the air and how much resistance it offers. Crewmen work to get the best "drag horsepower" rating they can, determining how much horsepower it will take to move a vehicle through the air at a certain mile-per-hour rate. At faster speedways teams strive to get the lowest drag number possible for higher straightaway speeds.
Air Pressure
With the advent of radial tires with stiffer sidewalls, changing air pressure in the tires is used as another setup tool that is akin to adjusting spring rates in the vehicle's suspension. An increase in air pressure raises the "spring rate" in the tire itself and changes the vehicle's Hankling characteristics. If his race vehicle was "tight" coming off a corner, a driver might request a slight air pressure increase in the right rear tire to "loosen it up."
Apron
The paved portion of the racetrack that separates the racing surface from the (usually unpaved) infield. It is usually flat in comparison to the racing surface. If a car has a problem, the driver goes there to get out of the way.
ARCA
Automobile Racing Club of America. The organization that governs and makes rules for ARCA racing. Many of ARCA's stock cars are hand-me-downs from NASCAR's Nextel Cup and many ARCA drivers go on to race in the Nextel Cup.
Backstretch
The section of the track located on the opposite side of the track of the start/finish line. On an oval track, it is between the second and third turns.
Bubble
A driver who is sitting "on the bubble" is the slowest driver of the top 25 during first-round qualifying. The driver can be knocked off the bubble, meaning bumped out of the field until second-round qualifying.
Camber
Camber addresses the angle at which a tire makes contact with the track surface. "Positive camber" indicates the angle of the tire is tilted away from the vehicle's centerline while "negative camber" indicates the tire is tilted toward the centerline. A typical oval track setup would have positive camber in the left front and negative camber in the right front to help the vehicle make left-Hank turns.
Carburetor Restrictor Plate
A thin metal plate with four holes that restricts the flow of air into and engine’s carburetor, thus reducing horsepower and speed. It is used to slow down the race cars at the superspeedways, Daytona and Talladega.
Check Valve
A safety valve that prevents fuel spills if the car turns over.
Dirty Air
The turbulence created in the air flow behind a race car. This occurs a little further back behind the car than the vacuum created during drafting
Downforce
The air pressure traveling over the surfaces of a race vehicle creates "downforce" or weight on that area. In order to increase corner speeds teams strive to create downforce that increases tire grip. The tradeoff for increased corner speeds derived from greater downforce is increased drag that slows straightaway speeds.
DNF
Did not finish.
DNQ
Did not qualify.
DNS
Did not start.
|
