A

AAA: American Automobile Association. This is the large nationwide car club that offers services such as travel assistance, roadside service.  AAA was once the organization that sanctioned most of the "legitimate" racing in the United States; its Contest Board sanctioned the Indy 500 and all Indy car racing in the U.S. until 1955 (when the Contest Board was disbanded). AAA is no longer involved in racing, but actions that it took in the '40s and '50s led indirectly to the formation and growth of NASCAR and USAC, and the ramifications of those actions are still with us today.
AARA: Antique Auto Racing Association. Sanctions Vintage Open Wheel exhibition racing. 
ABC: Refers to the progression of a stock car drivers training or career through three specific series, A-ARCA, B-Busch, and C- (Nextel) Cup.
ABC Money: Awards given to drivers or team owners who participate consistently in a series.
Abrasion: The act of or effects from friction or stress between two surfaces.
ABS: Anti-Lock Braking System. Anti-lock brake systems are designed to sense wheel locking before it occurs and then release the brakes so that loss of control does not occur..
ACCUS: Automotive Competition Committee of the United States. This is an umbrella organization, which includes representatives from CART, NASCAR, IMSA, SCCA, NHRA, USAC, and as of November 1997, the IRL. It handles cross licensing between sanctioning bodies in the U.S., and serves as the U.S. representative to FISA, the international auto racing coordination body.
ACES: Atlantic Coast Enduro Series.
Ackerman: The effective change in toe angle as the wheels are turned through their range of steering motion. This value is described in percentages of change. Frequently confused with bump steer.
ACOT: Atlantic Coast Old Timer Racing Club. 
ACRL: American City Racing League.
ACT: American-Canadian Tour, a former rival to ASA. ACT was similar to, but smaller than, ASA; they sanctioned similar classes of cars, mainly in the Upper Plains and central Canada. Tom Curley, the sanctioning body's owner, shut it down at the end of the 1995 season.
Adding Spoiler: Changing the direction of a wing or spoiler to add more downforce.
Adhesion: The amount of stick between two surfaces. Adhesion usually applies to objects at rest where traction applies to objects in motion.
Aero: Abbreviation used when referring to aerodynamics.
Aerodynamic Balance: A state of equilibrium between the front and rear aerodynamic downforce.
Aerodynamics: The science studying the forces exerted on racecars surfaces by air in motion and how it affects downforce, drag, and lift.
Aero Grip: Traction provided by down forces applied to the car’s surfaces and transferred to the tires.
Aero Loose: When two cars are close together and the lead car has less air being applied to its rear spoiler. This causes the car to have less rear downforce, which causes it to be loose in the turns.
Aero Push: When two cars are close together and the trailing car has less air being applied to its nose. This causes the car to have less front downforce, less turning ability, which then causes the car to push up the track.
AFCS: American Funny Car Series. Sanctions Drag Racing in the United States. Formally known as United Drag Racers Association.
After Market: Generally, the replacement parts and high performance products market.
AFR: Abbreviation for Air/Fuel Ratio. The mass of air inducted divided by the mass of fuel inducted.
A-Frame: Either the upper or lower connecting suspension piece locking the frame to the spindle.
Agricultural Racing or Excursion: When a car leaves the track and runs through the grass.
AHDRA: All Harley Drag Racing Association.
AHRA: American Hot Rod Association. Sanctions Drag Racing in the United States.
Air Box: Housing for the air cleaner that connects the air intake to the carburetor.
Air Dam: Used to direct or block airflow. Located on lower front valance. Used in front to prevent airflow to undercarriage, intended to prevent turbulence and lift.
Air Filter: Element used to keep particles from entering the carburetor and engine.
Air Foil: A stabilizer, generally used to create down forces, increase stability, and tire-to-track adherence at high speeds.
Air Pressure: The amount of air inside the tire pressing outward on each square inch of tire; expressed in pounds per square inch (psi) or kilopascals (kPa), the metric designation for air pressure. This should be expressed in "cold" or "hot" values and varies with atmospheric conditions.
Air Wrench: In general, any power wrench powered by compressed air, but often used to refer specifically to the special power wrenches used to change tires during a pit stop. 
AIS: The American Indy car Series, a low-cost series for Indy car racing. This series keeps costs low by using cast-off CART cars and by using an engine equivalence formula allowing teams a wide variety of engine choices. Currently, the series is defunct, but existing cars are still used in vintage competition.
Alcohol: When used to refer to racing car fuel, nearly always means methyl alcohol, or methanol. Ethanol is very seldom used for racecars (it costs too much), and other types are never used.
Alignment: The state in which all wheels on a vehicle are pointed in the optimum direction relative to the chassis.
All Pro: A touring series for Late Model cars, running mostly in the South. Created by super-promoter Bob Harmon, who sold the rights to the series to NASCAR in 1992. All Pro cars are quick and light, and often have much higher cornering speeds than other racecars on the same track. At one time, All Pro cars were notorious for high cornering speeds which resulted in boring, one-groove racing, but in the last few years NASCAR has made rules changes to correct this situation. Series was renamed the Kodak Southeast Tour in 2003.
All-Season Tires: Passenger car tires that are designed for use on dry and wet pavement, and also provide traction in snow and ice. 
Alphanumeric: A term for describing something using both letters of the alphabet and numbers. Used in describing tire sizes.
Altered: A general description of a racing vehicle featuring an open cockpit, tubular frame, center driving position, and altered, cut down body from a passenger vehicle. Popular altered body styles were originally produced overseas including the Anglia, Fiat, and Bantam. Can also refer to a car or portion of a car that has been changed in some way.
Alternate Starter: A practice, which used to be common in oval-track racing but has now just about died out. An alternate starter was the fastest (or sometimes the two or three fastest) among the cars that did not qualify for the race. Many races used to have rules that substitution of cars or drivers after qualifying was not permitted; if a driver crashed his car after qualifying, or were otherwise unable to start the race, that driver and car would have to withdraw. In this event, an alternate starter would be added to the field to take the place of the withdrawn team.
Alternator: A belt-driven device mounted on the front of the engine that recharges the battery while the engine is running.
AMA: American Motorcyclist Association. Sanctions Motorcycle events throughout the United States.
Amateur: A beginner or novice in the sport. It is the opposite of Professional.
Ambient Temperature: The temperature of the surrounding air.
AMRA: (1) American Motor Racing Association. Sanctions Open Wheel Modified racing in the US and Canada. (2) American Motorcycle Racing Association. 
AMSA: American Mini-Sprint Association.
Angle of Attack: The angle of a car or wing relative to the direction of travel.
ANRA: American Nostalgia Racing Association. Sanctions Nostalgia Drag Racing.
Anti-Sway or Anti-Roll Bar: A suspension component that links the left and right side suspension movement together. This is a torsion spring that limits the amount of lean that a vehicle will develop in a turn. It can be used in either the front or rear of a vehicle. It is a primary tuning device for handling characteristics. Also called "sway bar," roll bar, and anti-roll bar.
AOAS: American Outlaw Action Series.
Apex: The point in a turn where the car is turning most sharply. By definition, the apex is usually the slowest part of the turn; the car slows down into the apex, and then accelerates out of it. (However, this rule is sometimes violated by the use of unusual cornering techniques.) See also diamonding. Some turns on road courses may require more than one apex.
A-Post: The post extending from the roofline to the base of the windshield on either side of the car.
Appearance money: A guaranteed payment from the promoter or sanctioning body to a driver or team just for showing up, regardless of how that driver or team does in the race. Programs with names like "Winners' Circle" or "Appearance Plan" which pay per-race bonuses to drivers or teams, which have been regular entrants and have run well in the promoter's events or series.
Apron: An area on the inside of the track for cars that are going slowly. At high-banked tracks, the apron has less banking, so that cars that aren't up to speed won't slide off. The apron is also used as the approach to the pits, and as the merge-in area for cars exiting the pits. See also warm-up lane.
A/R: The size of a turbochargers turbine housing. “A” refers to the area of volute at a specific cross-section; “R” is the radius of the center of that area.
Aramid: A synthetic fabric used in some tires that is (pound-for-pound) stronger than steel. Example: Kevlar
ARCA: Auto Racing Club of America. Sanctions a national Stock car series, and several regional series. Founded in 1953 as the Midwest Auto Racing Club, it has evolved a number of regional racing series in the Midwest and West over the years. Its national series, the ARCA Supercar series, has the distinction of being the only nationwide Stock car racing series today that runs on both paved and dirt tracks. ARCA has a longstanding relationship with NASCAR, and some of its races are run as support events for Winston Cup races. Many up-and-coming drivers use ARCA to get superspeedway experience, since they run more superspeedway events than BGN does.
ARCA Invaders: Derogatory name for NASCAR teams or Drivers that enter in an ARCA Series event.
ARDC: American Racing Drivers Club.
Arm Restraints: Straps that attach to a driver's arms to limit the range of motion of the upper arm and by doing so keep the forearms and hands in the car. Sometimes required in Sprint and Midget racing; these cars are capable of flipping and rolling very violently, and the arm restraints keep the driver's arms from slipping out of the roll cage and getting crushed by the car in a roll. Similar to the purpose served by the window net in a Stock car.
Armco: A brand name for one brand of corrugated steel barrier widely used for guardrails on highways. In the '70s, many racetracks experimented with using Armco instead of concrete for crash walls. In this application, the steel barriers have been largely unsatisfactory, too easily damaged and in need of frequent repair. (Also, they are unsightly when damaged.) For this reason, most tracks are now phasing Armco out, in favor of concrete walls.
ARPI: Auto Racing Promotions.
ASA: American Speed Association. Sanctions a Stock car series (the ASA Racing Series) that operates mostly in the Midwest and Southeast, although they have enough dates in other parts of the country that their series is usually considered national. Since 1992, this series has been an innovator in reducing the cost of participation, and many regard it as being the prototype for the future of Late Model type racing. In addition, ASA sanctions weekly racing at tracks mainly in the Midwest. Founder Rex Robbins sold ASA to Georgia businessman Steve Dale in 2003.
ASCA: Arizona Sprint Car Association.  
ASCC: Atlantic Sports Car Club.
ASCoC: All Star Circuit of Champions. Sanctions Sprint car racing in the United States.
ASCS: American Sprint Car Series. Sanctions Sprint Car racing in the United States.
ASCT: Alaska Sprint Tour. 
ASM: All Star Midgets. Sanctions Midget and Dwarf car and Modified Lite Racing.
Aspect Ratio: Tire size term used to compare the tire width to the sidewall height. It is a percentage of the sidewall height compared to the tire width.
ASRTS: All Star Race Truck Series.
ASSC: Alaska Sports Car Club.
Assembly: Typical description of a wheel and tire unit. This can include a tube or liner as well.
Associate: A sponsor that puts up a small amount of money for a race team, and consequently gets its name on a less visible area of the car (such as the rear bumper, or the B-pillar between the side windows).
Atmo Engine: Engines, which use natural or atmospheric airflow as opposed to forced induction. NASCAR, Formula One and NHRA Pro Stock cars use "atmo" engines while Indy and NHRA Top Fuel and Funny Car engines use forced induction engines.
ATQMRA: American TQ Midget Racing Association.
Attenuator: A device mounted at the rear of an IRL car to absorb impacts to the rear end. The IRL new cars originally had a problem with the rear of the car being very stiff and transmitting rear-end impacts to the driver, and the attenuator (which is a large block of neoprene rubber) was an attempt to alleviate the problem. The rear-end stiffness problem has since been solved, but the attenuator remains as an additional safety device.
Attrition: The rate at which cars drop out of a race, due to mechanical failure or wrecks. Attrition is said to be high when few of the cars that start a race finish it.
Australian Pursuit: An odd form of racing which was popular in the early days of stock car racing, but has just about disappeared now. In Australian pursuit, each car that is passed by any other car during the race is black-flagged and eliminated from the race. The winner is the last car left on the track (or the first car to finish out of those remaining after a certain number of laps). Australian pursuit is usually considered to be a novelty event.
Autoclave: A complex oven for curing parts made of carbon fiber.
Axle: The pole or shaft on which a wheel turns. Rotating shafts connecting the rear differential gears to the rear wheels. Drive unit connecting the transmission to the front hubs on front drive vehicles
Back to top

B

Back Gate: Literally, the gate on the back stretch at a short track where car trailers or transporters are let into the pits or garage area, but the term is used by promoters to mean the number of cars and teams that actually show up and attempt to qualify for a race. It's an axiom in the racing industry that the back gate (number of participating cars) has a direct effect on the front gate (number of paying spectators), and so good promoters work hard at keeping their back gate as high as possible.
Backing It In:  Term used to describe a non-wing sprint car's entry into a corner. The car enters the turn in a slide with the rear of the car leading the front of the car. Also refers to a crash involving the car going back first into the wall.
Back Pedaling: Most commonly used in drag racing, the magical art of a driver easing out of the throttle to regain traction and avoid or stop tire shake. Difficult to achieve, the driver must anticipate the problem and pedal before the car is too far out of shape, all in less than 1/2 of a second.
Back Marker: A car that is many laps behind in a race. Also used as a derisive term to refer to drivers who are consistently slower then the majority of the field.
Back Out or Back Off: When a driver takes his foot off the gas pedal and slows down.
Back Stretch: The straightaway on a common oval track found between turns 2 and 3 on the opposite side from the start/finish line.
Backup Car: A complete second car used if a team’s first car is damaged.
BADGER: Badger sanctions Midget racing.
Bag Tank: Deformable fuel tank made from high strength rubber that is designed to flex and not rupture during an accident.
Balaclava: See head sock. Nomex or fireproof fabric for head and face protection
Balanced: The state in which a tire and wheel spin with all their weight distributed equally. Also refers to a cars setup being correct.
Ballast: A controlled amount of weight, functionally positioned, used to help car meet class weight requirements.
Ball Joint: A component of the front suspension consisting of a ball mounted in a socket that allows steering control in a stock car.
Bank/Banking: As applied to racetracks, the angle from the horizontal at which a corner or straight is tilted. Banking a corner increases cornering speed by converting some of the sideways centrifugal force to downward force, in much the same way that an airplane banks to make a turn. (It also improves drainage.) Bank is measured in angular degrees from the horizontal. The highest-banked track in the U.S. currently being used for racing is in Bristol, TN; it has 36-degree banking in the corners. The highest-banked superspeedway is Talladega, with 33-degree banking. Daytona has 31-degree banking. (By comparison, Indianapolis has only 9-degree banking, so it is not true that "superspeedway" is synonymous with high banks.)
Barge Board: Aerodynamic device placed in front of the sidepods or a suspension piece to smooth the airflow.
Barnstorming: Staging of an informal series of races by a touring group, often on temporary or jury-rigged racetracks. Many barnstormers engaged in hippodroming. A popular form of racing in the '30s and '40s when race cars were rare and sanctioning bodies were rarer, barnstorming has just about died out now in the U.S., although there are still some touring groups staging events such as stunt shows and demolition derbies.
BCRA: Bay Cities Racing Association.
BDC: Abbreviation for Bottom Dead Center. The position of the piston at the bottom of its stroke.
Bead: A round hoop of steel wires, wrapped or reinforced by ply cords, that is shaped to fit the rim; holds the tire onto the rim.
Bead Lock: A device used on some short-track racing cars to positively fasten the tire bead to the wheel rim. Particularly with low-pressure tires often used on dirt tracks, a bead lock keeps the tire on the wheel, and prevents the tire from slip rotating around the wheel, which can cause the bead to break.
Bead Wire: The steel wire wrap that is used to construct the bead package.
Beauty Bar: Design treatment that typically separates the sidewall from the shoulder of a tire.
Behind the Wall: Referring to taking a car into the garage area behind the pit wall to do major repairs.
Bell Housing: A cover shaped like a bell that surrounds the flywheel and clutch that connects the engine to the transmission.
Belly Pan: Generally, a skin of aluminum or fiberglass used to cover the under carriage of vehicle, assisting in preventing turbulence and air drag.
Belt: A rubber-coated layer of cords that is located between the plies and the tread. Cords may be made from steel, fiberglass, rayon, nylon, polyester or other fabrics.
Belted Bias Tire: A pneumatic tire with a body similar to that of bias tires, but which also includes two or more belts under the tread.
Belt Line: The line running around a cars body formed by the bottom edges of its glass panels.
Belt Package: The entire grouping of belts in a tire.
Bench Racing: Talking about racing; what racers and race fans do in the winter, or any other time when there's no real racing going on.
Bend: A shallow turn in the track.
BGN: The NASCAR Busch Series, previously known as the Busch Grand National. A Stock car series sanctioned by NASCAR. The cars are similar to Winston Cup cars, the main differences being smaller carburetors, less horsepower, and prohibitions on exotic materials.
Bias Ply Tire: Bias Ply tires are constructed of layers of rubber-coated plies composed of textile cords placed upon each other at approximately 30-45 degree angles. These plies are then wrapped around the bead wires. As a result of a tire being bias in design it will have a circumference that varies from tire to tire. Because of its design a bias tire can expand due to increased air pressure or due to heat generated during use. This allows a team to tune their cars setup and stagger in order to help the car handle better. Bias-ply tires have many limitations. Since the plies were placed at angles to each other, the casing is subjected to strong friction due to inter-ply shearing, which builds up heat and increases tread wear due to a higher slip angle. The positioning of the plies also limits the tire’s ability to provide both superior handling and ride comfort. One big advantage of bias tire is the lower tire cost. Bias tires are also much more tolerant of the set up than radial tires. It is easier to set them up and they are typically easier to drive at the limit of traction. Bias ply tires like higher slip angles, in the area of 3°-5° and work best with less than 1 degree of camber.
BIDCA: Badger-Illini Classic Modifieds. 
Big Block: As used today, usually refers to a big-block Chevy engine, although in context it can refer to a big-block engine from any manufacturer. Background: In the 1960, American manufacturers commonly sold all cars except for their economy lines with V-8s; engines of various displacements were created from the same basic engine block by using different bore, stroke, and cylinder head measurements. However, when consumers begin to demand more powerful, larger-displacement engines in the '60s, makers found that there were limits to the displacement that could be gained by adjusting bore and stroke, and so they each designed a second, larger block design for these larger-displacement engines. So, racers begin referring to the two V-8 block designs from any particular manufacturer as their "small block" and "big block". Generally, the small block was used for engines ranging from 250 to 400 cubic inches (4.0 to 6.3 liters), and the big block was used for engines of larger than 400 cubic inches. Big blocks are seldom used for production vehicles today (some larger trucks being the main exceptions), but some blocks are still manufactured in low quantities for racing.
Big One, The: Refers to a wreck involving many racecars during a race usually at one of the bigger speedways such as Daytona or Talladega.
Billet: Raw material form of forged metal that can be machined.
Binders: Another name for brakes.
Bite: The amount of grip the tires or car has with the track.
Black and Red Flags together: Indicates the end of a practice or qualifying session. All cars should exit the track and go to the pits or garage area. Checkered and red, or checkered and black, flag combinations may also be used.
Black Box: In car high tech electrical systems. These would control most engine functions. More technically referred to as the Engine Electronic Controls, the Engine Control Unit or the Engine Management System. May also include measure devices to record information during testing.
Black Flag: Report to the pits. Used to call in a car, either because the team is to be penalized, or because the car presents some sort of hazard that must be fixed (e.g., leaking oil, loose bodywork, or going too slow). Generally, the driver has a small number (2-3) of laps to obey the black flag, and a driver who continues after that point will be disqualified. At many tracks, an electric signboard next to the flagman's stand is used to display the number of the car being black-flagged, to avoid confusion.
Black Flag with White “X”: Signals a racer that is ignoring a black flag that if he/she does not come in they will cease scoring that car.
Black Slick: A condition describing a dirt tracks surface when it still has enough moisture to keep the material packed, but has hardened and is taking rubber.
Blade: Term that some drivers use for a rear spoiler. 
Bladder: Device that contains the fuel and keeps it from spilling and catching fire in the case of a rear impact.
Bleach Box: Section of track before the starting line where cars spin the tires in water. In early drag racing, actual chlorine bleach was used in place of water, originating the name.
Bleeder Valve: This is a device mounted in a wheel. It is a valve that is used to keep air pressure constant during a race. Air pressure increases with heat and this valve opens and releases air until the pressure returns to a preset amount.
Blend Line: Line painted on the track near the apron and extending from the pit road exit into the first turn. When leaving the pits, a driver must stay below it to safely "blend" back into traffic.
Blind Rally: A race in which the route is not released until just before the start.
Blip: A short tap on the throttle.
Blistered: Condition where a tire is run at excessive temperatures causing the tread to turn into a semi-liquid state. This is characterized by visible porosity in the tread, and sections of tread separating from the body.
Blower: Another name for a supercharger.
Block: An area of raised (or surrounded by grooves or sipes) tread on a tire.
Blocking: Racing term for changing position on the track to prevent drivers behind from passing. 
Blower Belt: The belt that drives the blower on a dragster. Also see Gilmer Belt.
Blow Over: A drag racing phenomenon where a dragster, most often a Top Fuel car, flips over itself. Excess traction and weight transfer lifts the front wheels, then air pressure under the nose pushes the front end higher until the car eventually topples over itself. Drag racing legend Don Garlits experienced the first "blow over".
Blown Engine: (1) An engine that has suffered a catastrophic bottom-end failure, such as a broken connecting rod. Engines that have blown usually have suffered irreparable block damage and have to be junked. Blowing an engine frequently produces a huge cloud of smoke and leaves oil and pieces of metal all over the track, making a caution flag necessary. (2) An engine equipped with a supercharger.
Blue Oval: Refers to a Ford. The name comes from the shape of its logo.
Blue with Yellow Stripe Flag: A signal to lapped cars to move out of the way of faster cars. The actual rules associated with this flag vary considerably. In some series, a driver can be penalized for ignoring this flag; in others, it is strictly an advisory (and in fact, the flagman might not bother). Often referred to as the "move over" flag.
Blueprinting: The meticulous matching to factory specifications all parts and/or components. Dressing parts to absolute design callout or manufacturer's specifications.
B-Main: A second-chance race sometimes seen at an event that uses heat races to determine qualifying and starting positions for the feature. The B-main includes all cars that failed to finish in a qualifying position in their respective heat races, and a certain number of additional qualifying positions are available to the B-main's top finishers. Also called a "last chance" or "B-heat" race.  
BMARA: Badger Midget Auto Racing Association.
Board Track: An oval track whose surface and foundation are made from wood. Elaborate board tracks were constructed in the 1910's and '20s, mainly on the West Coast, in part because good paving materials for earthen works tracks were not available (modern asphalt having not been invented yet). These tracks, built to lengths as long as a mile, were built for spectacle and often featured banking in the turns exceeding 45 degrees.
BOB: Battle of the Bluegrass Tour.
Bobble: A slight wiggle or a brief lose of control that is recovered by the driver.
Bolt-On Parts: Term used to describe the parts that attach to the car's chassis.
Bomber: A Stock car class where old cars (often retrieved from junkyards) are raced, with few or no modifications allowed. Intended to be the absolute lowest-cost way of going racing at many tracks, but they also have the side benefit of providing a measure of comic relief during a tense night of racing. Also referred to as "Jalopy", "Wrecker", "Thunder Car", "Detroit Iron" "Coyote" etc.
Boost: The amount of pressure generated by a turbocharger or supercharger as it forces the air/fuel mixture into a forced induction engine.
Bore: The diameter of an engine cylinder.
Bottom Dead Center: The position of the piston at the bottom of its stroke.
Bottom End: The reciprocating and rotating parts of an engine that transmit the engine's power, including the pistons, crankshaft, connecting rods, and main bearings. See also top end.
Bow Tie: (1) Chevrolet, from the shape of its logo. (2) A series of cylinder heads made by Chevrolet for racing, mainly for use by Late Models and drag racers.
Box: Slang term for a transmission.
B-Post: Post extending from the roofline to the base of window behind the driver's head.
Brain Bucket: Slang term for a helmet.
Brake Duct: A tube that takes air from the front or side of a car and directs it to the brakes in order to cool them.
Brain Fade: A lack of focus that can lead to making a mistake during a race.
Brake Balance: The difference in braking force between one end or side of the car, and the other. Racing brake systems are usually designed so that the front-rear brake balance can be adjusted, with more force going to one end or the other as desired to improve handling characteristics (side-to-side brake balance adjustment is less common, and not allowed in many series). Sometimes, this is done with a knob in the cockpit that the driver can use to change the balance while driving.
Brake Fade: Condition that occurs when the brakes get so hot they are ineffective and braking power is reduced.
Brake Tuning: Using both braking and steering ability of the car between the turn in point and the apex of a turn.
Breakout: (Run Under) In Drag racing, when your elapsed time is quicker than your dial-in, this causes you to be disqualified.
Break Loose: Describes when the tires are pushed beyond their threshold and they lose traction.
Brickyard: Nickname given to the legendary Indianapolis Motor Speedway, which although paved now, used to have a brick surface.
Buildup: Term use to describe an increase in tire pressure due to the tire heating up (by running and brake heating) and internal humidity turning into steam. To help limit pressure buildup teams use nitrogen dried air, or other gas to lower internal humidity.
Bull Ring: A general term for a short track usually a half-mile or less where local weekly races are held.
Bump Drafting: A drafting technique where a trailing car that is rapidly gaining on a preceding car will actually hit the preceding car in the rear (gently), in order to transfer some momentum to the preceding car and speed it up, which because of the dynamics of drafting, results in both cars gaining speed. A dangerous technique commonly used on superspeedways.
Bump Rubber or Bump Stop: A piece of rubber used to stop the travel of the suspension.
Bump Steer: Un-commanded steering motion in a front wheel, caused by the wheel's changing its toe angle as it moves up and down. Usually considered undesirable. Great effort is made to minimize the condition by changing the geometry between the steering rack and the suspension control arms.
Burn Off: Burning fuel during the course of a race. As fuel is burned, the car becomes lighter and its handling characteristics change, challenging the driver and crew to make adjustments to achieve balance.
Burned Piston: A type of engine failure, which is the result of pre-ignition or excessive heat in a cylinder, usually because the air-fuel mixture has become too lean for some reason. (Alcohol-fueled engines are especially vulnerable to this.) A burned piston has its top surface transformed into something resembling the surface of the moon, and may even have a hole burned all the way through it.
Burnout: Spinning of rear wheels at high RPM to heat and clean drive tire rubber prior to a run, resulting in increased traction.
Busch: The NASCAR Busch Series, previously known as the Busch Grand National. A Stock car series sanctioned by NASCAR. The cars are similar to Winston Cup cars, the main differences being smaller carburetors, less horsepower, and prohibitions on exotic materials.
Busch Whackers: Derogatory name for Nextel Cup teams or Drivers that enter in a Busch Series event.
Bye Run: In Drag racing, a lone run given to a randomly chosen car, because of an unequal number of cars in the round.
Back to top

C

Calendering: A machine process that combines body-ply rubber and cord fabric together into a specified thickness.
Calipers: A component of the braking system that houses the piston, which hydraulically pushes the brake pad against the rotor.
Camber: One of the three major front suspension geometry adjustments. The camber angle is the angle between the plane of the wheel (think of it as the plane of the hub face, or the brake rotor), and the vertical. Negative camber is when the top of the wheel is leaning toward the car. Positive camber is when the top of the tire is leaning away from the car. This adjustment setting is described in degrees.
Can-Am: Sanctions TQ Midget racing on asphalt oval tracks.
Cantilever: This is a tire designed to increase the tread width when rules restrict the rim width. The most noticeable characteristic is the pronounced sidewall extension. These tires typically present a challenge to the service technicians when mounting and dismounting.
Cap: A metal or plastic screw on cap for the valve stem.
Carbon Black: Ingredient used in the manufacturing of tires. Acts as a filler but also adds strength and color to a compound.
Carbon Monoxide: Colorless, odorless poison gas created by the combustion of carbon-based fuels. 
Carburetor: A device mounted on top of the intake manifold that controls the air-fuel mixture going to the engine.
Carcass: The tire body beneath the tread and sidewalls; also called casing.
CARS: (1) Championship Auto Racing Series. (2) Classic Auto Racing Series.
CART: Championship Auto Racing Teams, one of the two organizations that sanctions Indy car racing.
CASA: California Asphalt Sprint Association.
CASC: Canadian Automobile Sport Clubs.
CASCAR: Canadian Association for Stock Car Auto Racing. 
Casing: The tire body beneath the tread and sidewalls.
Caster: It's the angle between the front wheel kingpin and the vertical when viewed from the side. (Think of it as the "hinge" that the wheel swings on when the steering wheel is turned). All modern suspension designs have the top of the kingpin leaning toward the rear of the car. Higher angles can provide improved cornering traction, but a side effect is that such angles require extreme effort on the part of the driver to turn the steering wheel requiring power steering. The measurement is described in degrees, as in degrees of rotation. In a modern suspension design the "kingpin" is better described as the intersection of the upper and lower ball joints.
Catch Can: A small can that is used to catch fuel that comes out of the fuel cell vent when it overflows (while being filled). Also: Most fuel cells today have a check valve in the vent line that prevents fuel from backing out of the vent line. This valve also prevents air from escaping the cell, which would make it impossible to fill the cell, so the catch can has a protruding snout that is shoved into the vent line, and forces the check valve open so the car can be fueled. This applies mainly to Stockcars; Indy cars use a vent hose instead.
Catch Fence: The fence along the wall that protects spectators from errant cars, parts, etc.
Caution: A period when a race is stopped due to an accident or other dangerous situation (such as rain, debris, or spilled oil) on the track. Indicated by the display of a yellow flag and light. The cars may continue moving around the track behind a pace car and no passing is permitted. In most cases laps run under caution are counted and cars are permitted access to the pits for service.
Caution Lights: At most tracks, a series of signal lights around the perimeter of the track that duplicates the functions of some of the flags. Commonly, old traffic lights containing red, yellow, and green bulbs. Some use strobe or flashing yellow lights in addition to a solid yellow. 
C.C: Cubic Centimeter, a metric unit of volume measurement, equal to approximately 0.061 cubic inch.
CDCRA: California Dwarf Car Racing Association.
Center of Gravity: A measurement used in chassis setup to determine the overall balance of a race vehicle and adjust handling characteristics. The center of gravity is an imaginary point located in the car where if raised by that point, the car would balance perfectly. Center of gravity changes work inversely in dirt and asphalt applications. Raising the C.G. on an asphalt car will reduce traction while the same adjustment increases traction on a dirt vehicle. The opposite is true of lowering the C.G.
Center of Pressure: The point on an Indy car under-wing, which receives the greatest amount of airflow pressure. This measurement is critical to setting front to rear balance, especially on superspeedways.
C.F.M: Cubic Feet per Minute. A measure of airflow.
Chalk Mark: A measurement of the circumference written on the tire. This is usually not a cold circumference but a measurement taken after the tire has been removed from the mold and inflated. This measurement is used a reference point for comparing tire sizes.
Championship Cars or Champ Cars: (1) Refers to front-engine Indy cars that raced at Indianapolis and other Indy car venues until about 1965. See also Silver Crown. (2) The term that CART began using for its cars in 1998 (after it was barred from using "Indycar" as the result of a lawsuit by the IRL).
Chassis: The frame of a racecar that provides a mounting point for the motor, suspension, steering, roll cage, and drive train components.
Checked Out: Expression when the leader drives away from the rest of the field and will seem impossible to catch.
Check Up: To slow down abruptly, either because of a problem with the car, or because of an incident occurring ahead. When a driver checks up, he/she is supposed to hold up their right hand and wave it, as a signal to following cars, but there isn't always time. Sudden checking up is a frequent cause of "secondary accidents" that occur behind an accident or spin.
Checkered Flag (black and white): The race is over. This flag is always shown first to the winner; each car gets to complete the lap that it is on, and then the race ends.
Chicane: An "S" like track configuration generally designed on a fast portion of a track to slow cars. Also referred to as "esses" or a "switchback."
Chili Bowl: A nationally recognized indoor Midgets race in Tulsa, Oklahoma.
Christmas Tree: An electronic starting device used in drag racing that incorporates calibrated lights displaying a visual countdown for each driver, activated by a designated official. See full and pro tree.
Chrome Horn: Bumping into the rear of the car ahead of you, to cause him to get a bit loose (so he'll slow and you can pass him), or just to express dissatisfaction with his driving. The term comes from the early days of Stock car racing, when the racecars were showroom cars of the '40s and '50s with the huge, chromed bumpers that were in style then. The chrome horn is regarded as a dubious technique at best and downright dirty at worst.
Chromoly: Also Chrome Moly. Short for Chromium Molybdenum steel. Very strong and light tubing highly adaptable for racecars.
Chunking: Condition in which rubber comes off a tire in chunks due to the tire being chemically treated or a bad or misused compound.
Chute: (1) Short for parachute or drag chute. Used to assist high-speed braking. (2) A straight away on a track.
C.I.D.: Cubic Inch Displacement. A measure of volume, used to measure cylinder volume.
CIFCA: California Independent Funny Car Association. 
Circuit: Any racetrack. Also refers to the entire slate of races on a season schedule.
Circulating: Driving around a track with a damaged and/or slow car to accumulate laps and, more importantly, points and prize money.
Circular: A track with no straights. There have been such tracks in the past; the old Reading, Pennsylvania track was a well-known example in its day. There are no significant circular tracks existing today. (However, Flemington, New Jersey, is a rectangular track with straights so short that it is driven as a circular track.)
Circumference: The measured distance around the tread portion of a tire.
Claim Rule: A rule that allows parts from one competitors' car to be purchased by other competitors at a set price. Usually applied to engines, claim rules supposedly keep the cost of racing down by making it unprofitable to spend a lot of money on illegal or exotic modifications.
Clean Air: Air without turbulence created in the wake of other racecars. 
Clevor: Name for a Ford production-based small-block V-8, which is the basis for the current Ford NASCAR Winston Cup engine. The engine is an amalgam of the best features from the "Cleveland" and "Windsor" engines of the '70s, and the "Clevor" name is a combination of the two names. Ford is now phasing the engine out of production, and it's unclear how much longer it will continue to race in NASCAR.
Clip: On a tube-frame Stock car, the front and rear sections are designed so that if they are damaged in an accident, they can easily be cut off (with a cutting torch) from the main part of the chassis, and a new section welded on. These replaceable sections are referred to as the "front clip" and "rear clip".
Clipping: (1) Minor contact between racecars. (2) Refers to hitting precisely, or "clipping," the apex of a turn.
CLMA: Colorado Late Model Association.
Closed Wheel: A racecar where the suspension, wheels and tires are mostly covered by the body.
Clutch: The coupling device that when engaged or disengaged connects or disconnects the engine to the transmission.
Clutch Can: Bell housing, the bell-shaped housing used to encase clutch and flywheel.
Clutch Lockup: The progression of the clutch-disc engagement controlled by an air-timer management system.
CMT: Carolina Modified Tour.
CNYMS: Central New York Mini-Sprints.
Cock Pit: Area in a car where driver sits.
Cold Inflation Pressure: The amount of air pressure in a tire, measured in pounds per square inch (psi) before a tire has built up heat from driving.
Cold Pits: When there is no racing activity on the track and the pits are open to people other than team members and racing officials.
Collected: Getting hit by an out-of-control car while trying to pass by or through an accident in progress.
Combinations: A teams groups of engines, gearings, suspensions, aerodynamic parts, and wheel and tire settings that they forecast will work under varying conditions and tracks. These combinations (also known as set-ups) are recorded and used as baseline when teams arrive at a track.
Combustion: The burning of the fuel-air mixture in an engine cylinder.
Combustion Chamber: The part of the cylinder within an engine block where the fuel/air mixture is compressed by the piston and ignited by a spark from the spark plug.
Come In/Coming In: When a tire gets up to temperature and begins gripping. May also be called “fire”. Some rubber compounds will “come in” quicker than others.
Competition Area: The staging lanes and racetrack surface.
Competition Yellow: A scheduled caution period during a race. It has the effect of drawing all the cars together, which can prevent the race from becoming a "runaway"; it also de-emphasizes the importance of pit stops by decreasing the number of pit stops that must be made under the green flag. Commonly used by ASA to reduce costs by making fast pit stops less important. See also halftime.
Compound: This refers to the mixture or durability of the rubber on the tread of the tire. Compounds are usually described as "hard" or "soft". The more abrasive the track is the harder the compound you would want to use.
Compression Ratio: The volume of the combustion chamber and cylinder when the piston is at the bottom of its stroke, divided by the volume of the combustion chamber and cylinder when the piston is at the top of its stroke. Higher compression ratios tend to increase engine efficiency.
Compressor: A machine that pressurizes and regulates airflow for delivery into tools or tires.
Connecting Rod: A metal rod used to connect the piston to the crankshaft.
Consolation Race: Sometimes called the "consy," this is a race for teams who fail to qualify for a feature race or main event. (Some people incorrectly use this term to refer to a B-main.) The consolation typically will come with a small amount of prize money for the top few finishers, or the promoter might offer to cover the day's expenses of the consy winner. The purpose of the consolation race is to encourage the teams that failed to qualify to come back and try again at the promoter's next event. See also back gate.
Constant Radius Corner: A turn that has the same radius throughout the turn.
Contact Patch: The area of a tire that is in contact with the ground.
Contingency Awards: Money or prizes that are awarded to race participants by parties other than the race promoter. The contingency award may be based on performance, on a team's use of a sponsor's product, or any other criteria that the party sponsoring the award feels like imposing. Some contingency awards require that the racecar carry a sponsor's decal.
Cool Down Lap: A lap run after taking the checkered flag in order to slow down before leaving the track.
Co-opertition: Slang term that combines the two words Cooperation and Competition. Describes the act of teams cooperating during competition. The best example is drafting at superspeedways to benefit both cars.
Cord: The strands of material forming the plies or layers of the tire. Cords may be made from fiberglass, rayon, nylon, polyester, steel or other materials.
Core: The mechanism in a tire valve stem that allows one-way passage of air. Also called "valve core".
Cornering Force: The sideways force or lateral gravitational (G’s) forces exerted on a car and driver while going through turns at speed.
Corner Worker: Racetrack or series safety staff that are located in the corners to notify drivers of any dangerous situations in the area.
Cosmetic Damage: A spot or location of damage that is not a structural problem to the operation of the tire.
Cowl: A removable metal scoop at the base of the windshield and rear of the hood that directs air into the air box.
Cowl Induction: Housing for the air cleaner that connects the air intake at the base of the windshield to the carburetor.
C-Post: The post extending from the roofline of a racecar to the base of the rear window to the top of the deck lid.
Crankcase: The area of the engine block that houses the crankshaft.
Crankshaft: The rotating shaft within the engine that delivers the power from the pistons to the flywheel, and from there to the transmission.
Crash: An incident where one or more cars are involved in a wreck.
Crash Clause: A special provision that is included in a racecar rental contract regarding the amount that the renter will pay the owner if the racecar is wrecked.
Crate Motor: In some series such as ASA, a similar motor is supplied to all competitors. This is mainly done to reduce costs and even the competition, similar to a specified tire rule.
Crew Chief: The individual responsible for all mechanical aspects of the racecar and strategic decisions during pit stops and the race.
Cross Weight: The percentage of weight on the right front vs. the left rear wheel.
Crossed Flags: (two flags furled and crossed in an X shape): Indicates that half of the distance of the race has been completed. Usually, in oval-track racing, the rules stipulate that once one-half of the scheduled distance has been completed, if some condition (such as weather) makes it impossible to continue, the race will be called and the current running order becomes the final result. The crossed flags are a signal that this point in the race has been reached. Also, there is sometimes a bonus award for being the leader of the race at the crossed flags.
Cross Thread: Stripping of the wheel stud threads when crewmembers hurriedly refasten lug nuts.
Crush Panel: On a tube-frame Stock car, a sheet metal panel that fills in the gaps between the firewall and the side body panels. If the crush panel gets damaged, engine heat (and frequently exhaust gas) comes into the cockpit, which can make the driver extremely ill.
CTS: Craftsman Truck Series.
Cure: The process of putting a completely assembled green tire in a press and forming into a finished tire.
Cushion: Area of the corner above the farthest outside groove on a dirt track where loose dirt builds up.
Cut: A sharp turn or a racecars ability to negotiate a turn. The car is cutting well means the car is able to turn well.
CVM: Canadian Vintage Modifieds.
CVSCRA: Carolina Vintage Stock Car Racing Association.  
Cylinder: A chamber in the engine in which combustion occurs and drives the piston.
Cylinder Head: The top or lid over the cylinder(s).
Cylinder Liner: A circular housing that the piston moves in when the cylinder is not an integral part of the engine block. Also referred to as a “sleeve”.
Back to top

D

DAARA: Daytona Antique Auto Racing Association.
Damper: Device used to restrict the travel of a part usually a spring.
Darlington Stripe: A streak of scraped-off paint that appears on the right side of a car, from having made light contact with the outside wall. The term originated at Darlington back in the '60s, when the track had Armco for its retaining walls.
Dash: An event that is usually six to eight laps in length. Starting lineup of this event is usually determined by combination of Qualifying and Heat Race results. The finishing order of this event usually determines starting order of the first three or four rows of the Feature event.
Date TIN: The alphanumeric mark located above the tire bead on the reverse sidewall. The actual "Date" portion of the TIN is only visible on DOT type tires.
Dead Pedal: A footrest found to the left of the operating pedals to give the driver a place to put his left foot during hard cornering.
De-Beading: This is when a tire dismounts from a rim. This is normally caused from low air pressure.
Decals: A tradition as old as Stock car racing itself. Decals are a low-budget form of advertising that sometimes provides rewards that are small, yet important to struggling teams. Contingency awards are sometimes tied to the display of decals.
Deck Lid: The trunk lid. On most Stock cars, the trunk is vestigial, but the lid remains for access to the fuel cell, oil tank, battery, and other things that might be stashed away in that space.
Decreasing Radius Corner: A turn that has a smaller radius during the last half of the corner.
Deep Staging: In drag racing, when the racer inches his car forward, not completely passed the starting line (staging line) so much as to turn off the pre-stage light. This technique is often used to break the concentration of your opponent at the line. Deep staging increases E.T. but lowers your reaction time.
Defect: A general description of a manufacturing flaw. This could be cosmetic or structural in nature.
Delamination: Visible circumferential lines that occur when spiral tread wraps open up. This condition is usually cosmetic but in extreme conditions can be a performance problem.
Depth Holes: Cavities located in the tread surface that enables wear measurements.
Detroit Locker: A brand name of a ratcheting (limited slip) rear end commonly used in Winston Cup.
Dialed In: When a cars setup is in an ideal state.
Dialing In: The driver and crew making setup adjustments to for better handling. 
Dialing Under: Allows competitors in Stock and Super Stock the option of selecting a time faster than the National Index. Applied in handicap elimination racing where breakout is in effect.
Dial-ins: Driver's predictions of E.T.'s their cars will run in their first eliminations.
Diameter: The height of the tire (usually unloaded). 
Diamonding: Taking corners by driving into the corner fairly straight, making a sharp turn in the middle of the corner, and then driving out fairly straight (such that, as the car goes through the corner, it moves from the inside to the outside and then back to the inside). On an oval, this causes the car to describe a diamond-shaped trajectory around the track, hence the term. This is, in a way, the opposite of the standard technique for taking a corner, and often results in slower lap times, but it may produce faster times from a car that is severely pushing, or on a very slick track.
Diaper: A blanket made from ballistic and absorbent material, often Kevlar, which surrounds the oil pan and serves as a containment device during engine explosions. Also used to prevent fluid leaks from damaging racing surface during indoor racing events.
Dicing: Close, exciting driving between 2 or more racers. Positions are exchanged frequently.  
Direct Drive: When a drive train is directly connected between the engine/crankshaft and the axle without a clutch.
Directional: Usually refers to a tire that is only to be run one way and not reversed. Indicated by directional arrows. This is due to the construction of the tire. Running a directional tire the wrong way can result in its destruction.
Dirt Track: A track, which is not paved, but rather has a dirt (usually red clay, or some mixture including clay) surface. Dirt tracks host mainly Late Model, Midget, and Modified classes in weekly racing and some touring series. Dirt tracks are nearly always short tracks; most range from 1/8 to 1/2 mile.
Dirty Air: An aerodynamic term for turbulent air currents caused by fast-moving cars. Can cause a trailing car to lose control.
Dismount: Removing a tire from a wheel.
Displacement: In an engine, the total volume of air/fuel mixture an engine is theoretically capable of drawing into all cylinders during one operating cycle. Described in cubic inches or cubic centimeters.
Disqualification: The most severe during-race punishment that a sanctioning body can impose. Disqualification is imposed only for the most severe infractions, such as ignoring a black flag or deliberately wrecking another car. It may also be imposed after the fact for severe technical violations, which may not be discovered until after the race, such as having an engine that is too large or carrying illegal equipment. Note that disqualification does not necessarily mean that the disqualified car finishes last; usually for a during-race infraction the scoring simply stops counting that car's laps at the time that the infraction is committed. A disqualification will nearly always bring about some other penalty, such as a monetary fine, a point's fine, probation, or suspension.
Dive: The amount the front end of the car lowers during deceleration or braking. Usually before entering a turn.
DNF: Acronym for "did not finish". The opposite of running at finish. Most racing box scores will list, for each car, either "running" or a very brief reason why the car DNF'ed, such as "engine" or "accident".
DNQ: Acronym for "did not qualify".
DNS: Acronym for "did not start". See also alternate starter.
DOHC: Dual Overhead Cam. Engine with two camshafts over a bank of cylinders; generally one cam operates the intake valves, and the other the exhaust valves.
Door Bars: Term used to describe the side protection bars built into most full-bodied racecar roll cages. Often, 3 or 4 horizontal bars are joined to the front and rear upright support bars to form the door bar structure.
Door Car: As the name implies, any drag racing vehicle with functioning doors. Although they resemble passenger vehicles, Funny Cars are not door cars, as their doors do not function.
Dope: (1) Slang term for the homebrew fuel mixtures that were used in Indy car racing in the '20s and '30s. In the days when available gasoline was very low in octane, teams often mixed their own gas so that they could run higher compression ratios. (2) Refers to the practice of treating tires with chemicals to alter their thermal and traction capabilities. Practice is illegal and dangerous.
DOT: Department of Transportation. Governing body that establishes regulations including tire labeling and performance standards of tires that are run inside the United States on public roads and highways.
DOT Markings: A code molded into the sidewall of a tire signifying that the tire complies with U.S. Department of Transportation motor vehicle safety standards. The DOT code includes an alphanumeric designator, which can also identify the tire's manufacturer, production plant, and date of production and brand.
DOT Tires: Used to refer to street-legal tires that can be purchased by the public, as opposed to racing tires. Many lower-cost forms of racing require use of Department of Transportation (DOT) tires.
Double: Recent term for competing in the Indianapolis 500, and the Coca-Cola World 600 at Charlotte, in the same day ("running the double").
Doughnut/Donut: (1) Circular patterns that are formed on the side of a car when it comes into contact with the front or rear fenders of another car, and that car's tires (perhaps slightly protruding from the fenders) rub off the paint, forming a circular rub pattern. (2) Spinning a vehicle around and around by over-accelerating and turning at the same time, leaving rubber on the track in a circular or donut shape. (3) An extra piece of rubber inserted into a spring.
D-oval: Type of oval track that has a gradually, continuously curving front "straight". Michigan, Fontana, and Richmond are examples.
Downforce: Refers specifically to downward forces generated by aerodynamics, either due to the car's body shape or due to aerodynamic aids such as spoilers and wings (as opposed to downward force resulting from the car's weight or from G-forces). Downforce resulting from aerodynamics greatly increases the traction ability of the tires, but it also increases wind resistance, which is the trade-off for the increased traction.
Downshift: Moving the transmission to a lower gear.
Drafting: An aerodynamic phenomenon that occurs at high-speed tracks. A car following another car runs in a partial vacuum left behind the lead car, which means that it doesn't have to use as much power moving air aside. The lead car also benefits, because the following car is occupying the space where the air would otherwise be trying to flow back in and creating drag. Two cars in a draft can go faster than either of the cars could go by themselves.
Drag: The resistance a car experiences when passing through air at high speeds.
Drag Coefficient: A measured amount of how much drag an object creates while traveling through the air.
Drag Slot: When the starting grid for a race contains an odd number of cars (and assuming that the cars are started two-abreast, which is usually the case in Stock car racing), the last car in the field starts on a row by itself. That car is said to be in the drag slot.
Drift: A controlled slide through a turn or in an open area. Drifting has become a competitive sport.
Drive Line: All parts included in the drive train not including the engine and the transmission.
Drive Plate: A splined metal plate that transmits the rotation of the axle shaft to the hub assembly on solid axle suspensions. Variations of this design allows for 2-3 degrees of camber in the system.
Driver's Meeting: A meeting which usually takes place 10-30 minutes prior to a major race, conducted by race officials, and which all drivers in the race are required to attend. Often, the meeting is merely a formality, but sometimes it is used to discuss unusual conditions, pass on last-minute rules changes, or work out issues between drivers.
Drive Shaft: The shaft mounted between the transmission and the rear end differential.
Drive Shaft Strap: A U-shaped strap that is fastened to the bottom of the car, and passes beneath the drive shaft. Its purpose is to keep the drive shaft in the car if the shaft or one of its U-joints breaks. Use of drive shaft straps is mandatory by most oval track racing divisions. Sometimes referred to as a "Drive shaft hoop".
Drive Train: All parts that supply power to the wheels including the engine, transmission, drive shaft, differential, and hubs.
Driving Away: When a driver is pulling away from the field with little challenge from anyone else in the race.
Droop Limiter: A device that controls downward suspension travel.
Dropping a Cylinder: A generic term for any condition that causes an engine cylinder to stop producing power. In racing engines, this usually results from either an ignition failure, or from a valve failing to open or close properly. (The latter often results in the valve contacting the top of the piston, leading to engine failure.)
Drop the Hammer: When a driver puts the gas pedal to the floor.
Dry Hops: Process of spinning your tires on dry pavement creating off and on contact with the ground.
Dry Line: A clear or dry line on the track that develops after rain because of more frequent use.
Dry Sump: The type of oiling system used on most racing engines. In a dry sump system, oil that isn't being used at the moment is stored in a tank, away from the engine, eliminating the need for the "deep end" on the oil pan. 
Dry-Break Connector: A connector used for fueling apparatus (gas cans or hoses) that can be connected or disconnected under pressure without spilling any fuel.
Dry-Slick: A dry dirt track with little or no moisture or grip. Often associated with a dusty track.
Dry Weight: A car's weight without any liquids such as gas and oil.
Dump Shifting: Skipping gears while downshifting.
Durometer: A device used to measure the hardness of the rubber on the surface of a tire.
Dwarf Car: A racing car, with a vintage-replica body (usually of a car from the '30s or '40s) built on a tube-frame chassis, and usually with some type of 4-cylinder engine. Many dwarf-car divisions are spec series, with all competitors being required to purchase the cars from a specific builder, and with very few or no mods allowed. See also Legends.
Dynamic: Dimensions or descriptions that apply when an object (tire, suspension or car) is in use or in motion. (See "static")
Dynamic Weight Transfer: The transferring of weight from side to side during cornering, from rear to front during deceleration and from front to rear during acceleration.
Dyno: Short for dynamometer. A device used to measure the power output of an engine, in or out of a car, by applying its power to a load. The load is usually some form of brake or friction device (such as a water turbine). The term is often used loosely for any kind of test stand where engines are run out-of-car, whether under load or not. Recently, some people have also began using the term to refer to any piece of testing gear that tests the dynamic performance of a racing component, such as the "shock dyno".
Back to top

E

Early Apex: When a driver turns into a corner too soon.
Economy Run: When a driver drives conservatively to save the engine, fuel and tires.
EEC: Electronic Engine Control.
EGT: The Exhaust Gas Temperature. 
EIRI: Except in rare incidents.
EKRL: Endurance Kart Racing League.
Elapsed Time (ET): The total time it takes to get from the starting line to the finish line. Each car must have its number on the side of the car, in the door area, and on the roof. Small numbers can appear on the nose, in the place where the headlights would be on a production car.
Electric Eye: A generic term for any electronic timing device.
Electrical: Sometimes used as an excuse for a car's retirement from a race when revealing the real reason would be embarrassing; for instance, if the engine fails in a race being sponsored by the engine's manufacturer. This type of prevarication isn't very common, fortunately, but it does happen. The reason why "electrical" is often used in these situations comes from an apocryphal story: a team, which had suffered a pyrotechnic engine failure, gave their reason out as "electrical." When an incredulous series official queried, he was told, "a rod that went through the block knocked the alternator out, so it was an electrical problem."
Eliminations: When cars are raced two at a time, resulting in one winner and one loser "eliminated." Winner continues to race in a tournament-style competition.
End Plate: The vertical end portion of a wing.
Enduro: A short-track event, which runs at a longer-than-usual distance and with an abnormally large field. In an enduro, the lead cars start to enter lapped traffic after only a few laps. This makes the event more of a challenge to the driver to be smooth and stay out of trouble, rather than a speed and horsepower contest.
Engine Computer: A microprocessor that controls the functions of the engine, such as fuel delivery and engine timing. Almost universal in passenger car engines since about 1985, and Indy car engines have been using them since the late '70s. However, computer-controlled engines are still not permitted in NASCAR.
Engine Leasing: Process where a race team leases an engine from an engine builder for a specific length of time for a fee. All maintenance, rebuilds, and tuning are handled by the leasing company. Leases usually occur when teams do not have their own engine shop or when their product is inferior to other producers.
Entry: The line or point a vehicle enters into a turn.
Entry Level: A class of racing with a wide range of rules and types of cars that include Street, Pure, Hobby, Super, Factory, Pony, Mini, and Limited Stocks as well as Bombers, Road Hoggs, Thunder Cars, Cruisers, Roadrunners, some Sportsmen, Runabouts, Chargers, Figure 8's and many others.
EOQM: Eastern Outlaw Quarter Midgets. 
ERA: Englewood Supermodified Association.
ESDCA: Empire State Dwarf Car Association.
ESS: Empire Super Sprints 
Esses: An "S" like track configuration generally designed on a fast portion of a track to slow cars.
E.T.: (Elapsed Time). The total time it takes to get from the starting line to the finish line. Each car must have its number on the side of the car, in the door area, and on the roof. Small numbers can appear on the nose, in the place where the headlights would be on a production car.
Equalize: To gradually lose pressure in an inner-liner equipped tire, until the main carcass pressure equals the inner liner pressure. When this happens, the inner liner partially unfolds inside the tire and flops around, which can create a severe vibration.
Equal Loading: When two tires on the same axle have the same amount of weight applied or loaded.
Back to top

F

F1: Abbreviation for Formula One.
F.I.A: International Federation of Automobile Clubs. Sole international body governing motor sports outside the United States.
Fabricator: Team member responsible for the body of the racecar.
Factory Team: A team owned, operated, or sponsored directly by an automobile manufacturer.
Fall Off: Gradual or drastic deterioration of a tires performance during use.
FASCAR: Florida Association of Stock Car Auto Racing.
Feature: The main event at a weekly-racing session or regional (or, less commonly, a national) event. Typically, a short track running weekly racing will have several classes, and each class has a feature (possibly more than one) where most of the money and points for that class are awarded. Starting positions for the feature are often determined by running heat races.
Fence: Term to describe the barrier on the inside or outside of the tracks racing surface. I may be a wall or steel rail but still be referred to as a fence.
Ferrous: Containing iron, as in metals.
Fidgets: Slang for the Ford Focus Midgets.
Field: The group of cars that starts a race or the total number of cars in attendance. May also refer to the group of drivers and teams that competes regularly in a particular racing series.
Field Filler: Cars that enter an event to fill out the field of entrants. This is done in order for the series or promoter to present the advertised car count and the teams to get a guaranteed start and finishing position pay. These cars may start the race, complete a few laps, and then park.
Figure-8 Racing: Races run on a figure-8 shaped track. This is done by paving two lanes in an X shape through the infield of a conventional oval.  In a Figure-8 race, there is an intersection in the middle of the track, which the cars must navigate to avoid wrecks with crossing traffic.
Fill the Mirrors: When a driver is pressuring another driver so feverishly that the rear-view mirror is filled their pursuer.
Finish Line: Line, which determines winner and computes Elapsed Time.
Fire: When a tire gets up to temperature and begins gripping. May also be called “coming in”. Some rubber compounds will “fire” quicker than others.
Fire Bottle: A brand name for a model of fire extinguisher designed to be used in a racecar; sometimes used to refer to a fire extinguisher in general.
Fire Suit: The suit worn by the driver (or others potentially exposed to fire, such as a gas man), consisting of several layers of a fire and heat-resistant fabric such as Nomex or Kevlar. The development of fire suits in the late '60s cut down greatly on burn injuries suffered by drivers.
Fire Wall: A solid metal plate that separates the engine compartment from the driver's compartment of a racecar.
Fishtail: Aft lateral oscillation of a vehicle, generally the result of traction loss.
Flagman: Person who uses flags to signal various conditions to the drivers and teams. At weekly-racing events, the flagman is often the person who has the final say over the starting and stopping of the race, and handing out penalties to drivers who commit infractions. (In professional series, a race director generally has that responsibility.) Generally, the flagman stands on a platform that is elevated over the outside edge of the track, at the start/finish line. (In old films, one can see the flagman standing on the track, but that is rarely done now due to the obvious safety concern.) Also referred to as the starter.
Flags: Used by the flagman to signal various conditions to the drivers and teams. At most tracks, a series of signal lights around the perimeter of the track duplicates the functions of some of the flags.

• Black: A flag demanding a car and driver report to the pits either because the team is to be penalized, or because the car presents some sort of hazard that must be fixed. A driver who continues after that point will be disqualified. At many tracks, an electric signboard next to the flagman's stand is used to display the number of the car being black-flagged, to avoid confusion.
• Black and Red together: Flags indicating the end of a practice or qualifying session. All cars should exit the track and go to the pits or garage area. 
• Black with a White “X”: Signals a racer that is ignoring a black flag that if he/she does not come in they will cease scoring that car.
• Blue with Yellow stripe: A signal to lapped cars to move out of the way of faster cars. The actual rules associated with this flag vary considerably. In some series, a driver can be penalized for ignoring this flag; in others, it is strictly an advisory (and in fact, the flagman might not bother).
• Checkered (Black and White): The race is over. This flag is always shown first to the winner; each car gets to complete the lap that it is on, and then the race ends.
• Crossed flags: (two flags furled and crossed in an X shape): Indicates that half of the distance of the race has been completed. Usually, in oval-track racing, the rules stipulate that once one-half of the scheduled distance has been completed, if some condition (such as weather) makes it impossible to continue, the race will be called and the current running order becomes the final result. The crossed flags are a signal that this point in the race has been reached. Also, there is sometimes a bonus award for being the leader of the race at the crossed flags.
• Green and Yellow together: Used to indicate the start of a race, when it is necessary to start the race under caution. This might occur, for example, if it has rained before race time, the track is still damp, and the race needs to start by a certain time in order to meet television commitments.
• Green: Start racing, or resumes racing. The green flag is waved at the start of the race, and at the end of every caution period; it remains out until the next caution period, or the end of the race.
• Red: Race halted; all cars must drive slowly around to the start-finish line (or some other point designated by the officials) and then stop. Used when the track is blocked, or needs repair, or to signal a scheduled break in the race or when weather conditions make it unsafe to continue even at caution speed.
• Red with Yellow "X": Used by NASCAR to indicate that the pits are closed (in all of the NASCAR professional series, when a caution occurs, the pits are closed until the pace car has entered the track and the field is formed up behind it). An official positioned at the pit entrance holds this flag. Any car that passes this flag and enters the pits is subject to a penalty. Some other series use a similar flag to indicate that there is an emergency vehicle on the track.
• White: One more lap remains in the race. In NASCAR, a car may not pit or receive any form of assistance (for instance, a push from another car) after taking the white flag.
• Yellow: Caution period indicates that a wreck has occurred, or some other condition.

Flash Shield: A device to encompass the air inlet of a carburetor's sides, top, rear. To protect driver in case of engine backfire.
Flat: Description of a tire assembly that won't retain pressure.
Flat Out: To run a racecar at maximum speed.
Flat Spot: A portion of a tire worn down excessively due to locking the brakes or spinning the car.
Flip Ups: An aerodynamic device located in front of the rear wheels to direct airflow over the back tires.
Flopper: Slang term in drag racing to describe the Funny Car class. Derived from the fact that modern funny cars use a fiberglass body that "flops" down over the chassis.
Fly by Wire: A term, borrowed from aviation, to describe a control system where the driver, instead of directly controlling something through mechanical linkage, controls it indirectly through electrical actuators. In particular, refers to cars in which the steering, transmission, throttle, or braking is controlled in this matter.
Flywheel: A heavy metal rotating wheel that is part of the race car's clutch system, used to keep the crankshaft turning smoothly.
FMSA: Florida Mini-Sprint Association.
Footprint: The portion or amount of area of the tread that contacts the road.
Force Variation: A process to measure differences in tire/wheel consistency. Determines the highest portion of the tread in order to match it up to the lowest portion of the wheel for best performance and minimize tire/wheel assembly vibration.
Formula One: An open wheel series similar to Indy cars but with more sophisticated computer controls, higher rpm engines, and mostly run on road courses. Considered to be the highest form of motor sports.
Forward Bite: A general term used to describe the amount of force available to move the car forward. In setup, putting more forward bite in usually refers to adding more traction to the rear of the car.
Foul Start: Leaving the stage beam at the starting line before the green bulb illuminates resulting in immediate disqualification. Red lights at the bottom of the Christmas Tree signify a foul start.
Four-Barrel: The type of carburetor used in many types of racing.
Four-Link Suspension: Commonly used racing suspension. Found in all forms of racing, four link is characterized by four individual bars, two on each side of the rear end, used to control rear end movement and traction.
Four-Point, Five-Point: See harness.
Fours: Four-car-wide salute to the fans from the racers. Normally at the start of the night’s main event.
FPRS: Formula Pro Racing Series.
Frame: The main structure or chassis of the car.
Frame Rails: Main lengthwise component beams of the chassis or frame.
Free: The same as loose. A handling condition (known as "over-steer" to road racers) where, when the car goes through a corner, the rear end of the car wants to slide towards the outside of the turn. If the car gets loose enough, it will spin out. Adjustments can be made to “free up the car”.
Freight Train: A group of drafting cars lined up like a train.
Fresh Rubber: New tires.
Friction: Contact between two surfaces. Usually results in heat.
Front Clip: Beginning at the firewall, the front most section of a racecar.
Front Steer: An arrangement of the steering gear where the tie rods connect to the wheel hub at a point forward of the kingpin.  
Front Stretch: Main straightaway between turns 4 and 1 on an oval track.
FSCDRS: Fastest Street Car Drag Racing Series.
Fuel: Flammable liquid used to power internal-combustion engines.
Fuel Cell: A type of fuel tank that has a rubber (or similar) inner lining, to contain the fuel if the outer tank is punctured. Most also contain a foam or metal-mesh filling, which prevents fuel sloshing and keeps the flame out of the tank if a fire occurs.
Fuel Check: An area of technical inspection in which fuel is tested for compliance.
Fuel Injection: (F.I.) A system replacing conventional carburetion, which delivers fuel under pressure directly into the combustion chamber.
Fuel Pump: A device that pumps fuel from the fuel cell through the fuel line into the carburetor.
Fuel Stint: The amount of laps or time run on a full tank of fuel.
Full Bore: Running as fast as possible.
Full-Face: A helmet that covers the entire face and head. When used with a head sock, it provides full-uninterrupted coverage of the driver's upper body against fire, and the enclosure of the mouth prevents the driver from inhaling the flame during a fire. It also provides protection to the forehead and eyes, and makes separate goggles unnecessary.
Full Floater: A type of rear axle where the axle housing extends all the way out to the wheels, and the wheels are held on bearings fastened to the ends of the housing tubes. Works in conjunction with drive plates.
Full Tree: The method used to start cars at the starting line. The method used is one yellow light is used at a time, then the green light. As opposed to all yellow lights are lit at once then the green light (Pro-Tree). The reaction time used in full tree is .500.
Back to top

G

G’s: Gravitational forces exerted on a car and driver under acceleration, braking, and cornering.
Garage Area: A covered or enclosed area, usually in the infield of an oval track, where the racecars are stored and worked in when not on the track. The garage area is the place for performing repairs that are more extensive than possible in the pits. The garage area is protected from the "hot" area of the racetrack, and no fast driving is allowed there. Indy car and road racers sometimes refer to the "paddock" area.
GARRA: (Grand Am) Grand American Road Racing Association. Sanctions Sports Car racing events in the US and Canada.
Gas: Used to mean gasoline (as opposed to alcohol or other fuels). This usage appears more commonly in drag racing, where a division with the word "Gas" in its name means those cars in that division must run on gasoline, but it is also used some in oval track racing.
Gas Catcher: Pit crewmember that is responsible for the catch can. This person may also perform other duties during a pit stop.
Gasket: A thin material, made of paper, metal, silicone, or other synthetic materials, used as a seal between two similar machined metal surfaces such as cylinder heads and the engine block.
Gasman: The member of the pit crew who refuels the car. In stock car racing this person must lift heavy cans of racing gasoline (Usually 22 gallons weighing about 87 lbs. or 40 kg) up to the car's filler inlet. In Indy car racing, this person handles a large hose with a huge stainless-steel connector at the end, which delivers fuel from a tank on a stand behind the pit wall.
Gasoline: see gas
Gasoline Alley: The garage area at Indianapolis Motor Speedway.
Gasser: A dragster or any car that runs on gas.
Gather/Gathered It Up: Regaining control of a racecar after becoming loose or spinning.
Gathered Up: A car becoming involved in a wreck not his/her fault. Being “gathered up” by another car.
Gauge: An instrument, usually mounted on the dashboard, used to monitor engine conditions such as fuel pressure, oil pressure and temperature, water pressure and temperature, and RPM (revolutions per minute).
GCS: Golden State Challenge.
Gearbox: Racing term for a transmission.
Gear Ratio: The ratio of engine RPM’s to rear wheel RPM’s.
Gears: Circular, wheel-shaped parts with teeth along the edges. The interlocking of two of these mechanisms enables one to turn the other.
Gearset: Two or more gears used to transmit power.
Gilmer Belt: Toothed or splined drive belt used with matching pulley, generally a non-slip drive belt.  The large belt used to transfer power from the engine's crankshaft to the input shaft of a supercharger. Most are reinforced and molded to match the teeth of the drive gear.
Give Up: Gradual or drastic deterioration of a tires performance during use.
Glass Transition Point: The temperature that the tread rubber will freeze and crack. This temperature will vary depending on the rubber compound.
GLOSS: Great Lakes Outlaw Sprint Car Series. 
Going up through the Gears: Refers to a driver up-shifting from the lowest to the highest gear.
Gold Crown: The name that USAC used for its Indy car series between about 1970 and 1980. Prior to about 1970 there were few paved-track Indy car races; many races which were part of the "National Championship Trail" (which traces its lineage back to the AAA days) were held on dirt, using cars called Champ cars built for the purpose. By 1970, the Champ cars and the rear-engine Indy cars had diverged wildly, and so USAC decided to separate the dirt track races and form a separate series for them which was named the Silver Crown series.
Got Under: When a car out brakes another going into a turn and passes on the inside.
Graining: A pattern of nearly parallel ridges on a tires tread. Cause by over aggressive driving on a tire that has a compound that is usually too soft or has not been allowed to be brought up to a good operating temperature.
Grand Am: Grand American Road Racing Association. Sanctions Sports Car racing events in the US and Canada.
Grand Marshal: An honorarium, usually reserved for sponsors and celebrities. Feature races often have a grand marshal, whose most visible function is doing the traditional "Gentlemen, start your engines" bit at the beginning of the race.
Grand National: The original name for what is now known as the NASCAR Winston Cup series. The Grand National name was adopted in the early '50s, and persisted until 1971 when the series named was changed to Winston Cup, after its title sponsor. To make things confusing for historians, when the old Late Model Sportsmen series was re-formed into a touring series in 1982, it was given the name Busch Grand National. The Winston Cup name is now used generally to refer to the NASCAR top series, both before and after 1971.
Grand National East: This was a series created by NASCAR in 1972. It consisted of all of the dirt-track races which were removed from the Winston Cup series that year, both to reduce the number of races on the WC schedule and because the dirt races were considered old-fashioned and too stereotypically Southern. (Consequently, this year is generally considered to be the beginning of what is now called the "modern era" of NASCAR racing.) Without the Winston Cup stars, the Grand National East series races drew poorly, and the series died out after two years.
Grand National West: At the time that NASCAR created the Late Model Sportsmen championship for local and regional racers in the South and East in 1948, it recognized that it would be impractical for teams on the West Coast to tow their cars to the other side of the country to participate. Because NASCAR wished to maintain its ties with the West Coast hot rodders, it created a similar but separate series called the Pacific Coast Late Model series. In 1972, when the Grand National East series was created, the PCLM series was renamed Grand National West to be analogous with Grand National East, even though the two series were nothing alike in the cars, the racing, or the participants. Unlike the ill-fated East series, the West series survives today and a vestige of the name change can be seen in its current name, Winston West.
Grand Prix: This French term meaning grand prize is widely used to refer to a race. At one time in racing, it was used exclusively for a series' grand finale, usually the most important race.
Gray: Area on a paved track where nobody runs, particular in the corners. Sometimes it actually is visibly a lighter color than the groove. The gray area is often full of marbles and other loose material that causes a severe loss of traction for any car that goes there.
Green: (1) The state of the track when a green flag is in effect; the opposite of a caution period. (2) A track which is either newly paved, or has experienced heavy rain since the last time the track was raced on, or just hasn't been used in a while. A "green" track lacks the accumulation of tire rubber that builds up when the track is raced on, which changes the handling characteristics of cars that race on the track.
Green and Yellow Flags together: Used to indicate the start of a race, when it is necessary to start the race under caution. This might occur, for example, if it has rained before race time, the track is still damp, and the race needs to start by a certain time in order to meet television commitments.
Green Flag: Start racing, or resumes racing. The green flag is waved at the start of the race, and at the end of every caution period; it remains out until the next caution period, or the end of the race.
Greenhouse: The area inside the racecar, generally referring to the top inside part of the racecar, where the driver sits.  The greenhouse area is basically from the windshield to the back deck lid, and from the doorframes up.
Green Tire: A completely assembled tire that has not yet been cured. Also refers to an environmentally friendly tire that uses less oil.
Green Track: A track which is either newly paved, or has experienced heavy rain since the last time the track was raced on, or just hasn't been used in a while. A "green" track lacks the accumulation of tire rubber that builds up when the track is raced on, which changes the handling characteristics of cars that race on the track.
Green/White/Checkered: When a caution occurs near the end of a race, the series officials may choose to go passed the advertised race length to get the race in under green. They may finish the caution and then go green for one lap, followed by the white flag indicting one lap to go, and then finish with a checkered flag. Basically a 2-lap finish under green instead of finishing a race under a caution.
Grenade: An engine built to go very fast for a few laps, for qualifying. Grenade engines are usually built with lightweight parts and will often blow in spectacular fashion if run for more than a handful of laps.
Grid: The starting order of the field, in the physical positions that they will actually start the race. Also refers to the part of the track where cars are assembled pre-race.
Groove: (1) The line or path through a corner which drivers have found to be the fastest. Where the groove is depends on a huge number of factors, such as the type of paving, the car weight, tires, downforce, driving style, track and weather conditions, etc. It is not uncommon for the groove to change during a long race, particularly on a dirt track. (2) Channels that are cut or molded into the tread portion of the tire. These grooves make up the tread pattern.
Grooving: A term used when a tool with a blade is used to alter the tread pattern of a tire. When using this tool it will create a new groove in the tread surface. The size of the groove varies and depends upon the width of the blade being used. This method is used to increase traction by giving the tires more edges on the tread surface to grip with.
Ground Effects: Use of airflow under the car to create downforce. (The term "ground effects" comes from aviation, but there it means the opposite: the tendency of an airplane near the ground to float on a high-pressure cushion of air.) Most ground effect cars use passive tunnels to create a venturi effect, which draws air from under the car.
Growing: In racing, when tire circumference increases as speeds increase. Tire growth is important in heads-up classes where speed determines the race outcome. Less contact patch on the top end leads to more M.P.H. In oval track racing, when the circumference of a tire increases due to heat and pressure build up. Tire growth alters the stagger, and upsets the handling of the car. One advantage of radial tires is that they don't grow.
GTA: GT American Road Racing Association.
Guard Beam: Light beam positioned 16 inches ahead of the stage beam to prevent racers from using side panels behind the front tires to block the staging beams, thereby gaining a starting line advantage. If the guard beam is reached before the car leaves the staging beam, a red light is given and the car disqualified.
Gurney Flap: A small spoiler-like tab that sticks up (or down) perpendicular to an aerodynamic surface, such as a wing; it has the effect of increasing air pressure on that side of the surface, making it produce more force in one direction or the other. Perfected in the early '70s by legendary Indy car driver and designer Dan Gurney.
Gusset: A reinforcement addition adding web-like or triangulation reinforcement to car structure, usually welded in place.
Back to top

H

Hairpin: A slow, tight 180-turn which exits in the opposite direction a driver enters.
Half-Shaft: In a car with independent suspension on the rear wheels, the part that carries the engine power from the rear end to the wheels. (Or the front wheels on a front-wheel-drive car.) The half shaft must have some kind of mechanism in order to be able to move with an independently-suspended wheel, while still being able to transmit torque to the wheel; universal joints or constant-velocity joints are commonly used. The half shaft is so called because it is "half an axle".
Halftime: A scheduled break in a race that occurs when half of the scheduled laps have been completed. A red flag is flown, and all cars go to the pits for 5-10 minutes, where work can be done. The halftime is used when a racing series wants to de-emphasize the importance of pit stops. The NCTS series dropped it because they found that, eventually, there was little racing taking place in the first half of the race; teams were simply using the first-half laps as a test session in order to put in a finely tuned chassis setup during the halftime. May also refer to a competition yellow.
Halon: Special Freon Fire Extinguisher. Generally a 3% to 5% concentration will extinguish fire.
Hammer Down: The driver has the gas pedal "to the metal"- full throttle. 
Handicap: In bracket racing, when one car is faster than the other, the slower gets a head start. Handicaps are based on previous elapsed times or dial-ins.
Handling: A general term for the racecar's capability to go where the driver wants it to go on the track, and be fast in the process. See loose and push.
Hanford Device: A type of rear wing used by CART on superspeedways. The Hanford device is intentionally designed to produce very high aerodynamic drag, in an effort to slow down the extremely fast CART cars on superspeedways. Results have been mixed; the racing that results is sometimes compared to the effects that restrictor plates have had on Winston Cup.
HANS Device: Head and Neck Restraint System. A driver restraining system that straps over the driver shoulder and securely attaches the helmet to anchors to reduce the snapping motion of the driver's neck during an impact.
Happy Hour: The final hour of practice before an event, usually held the day before the race day and after all qualifying sessions and support races have been staged.
Hard Charger: The driver that has passed the most cars in the race.
Harmonic Balancer: An element used to reduce vibration in the crankshaft.
Harness: The safety belt system worn by a race driver. The basic racing harness is a "four-point" unit; it has four belt lengths that meet in the middle of the driver's pelvis. Two points form a conventional lap belt, same as in a passenger car; the other two go up the chest and over each of the driver's shoulders; unlike a passenger-car shoulder belt, they do not cross over the chest. In cars with a roll cage, they are fastened to a roll cage member behind the driver's seat. (In open-cockpit cars, such as Indy cars not having a roll cage, they are fastened to the part of the chassis structure behind the driver's seat.) The place where the four points meet has a one-lever disconnect that causes all four harnesses segment to unfasten simultaneously, for rapid bailout. Some series require a "five-point" harness, which adds a belt that goes through the crotch and the bottom of the seat; this prevents "submarining" (a term for when the driver slides out from under the lap belt in a high-speed frontal impact). Some shoulder harnesses have a horizontal strap that connects them and crosses the breastbone; this is called the "sternum belt", and it prevents the driver's breastbone from extruding out from between the shoulder belts.
Hat Dance: A routine performed by the winning driver where he is photograph in victory lane with each of the sponsors and sanctioning bodies hats.