When following another vehicle closely, the airflow off the lead vehicle does not travel across the following one(s) in a normal manner. Therefore, downforce on the front of the trailing vehicle(s) is decreased and it does not turn in the corners as well, resulting in an aero push. This condition is more apparent on the exit of the turns.
A number that is a coefficient of several factors that indicates how well a race vehicle will travel through the air and how much resistance it offers. Crewmen work to get the best “drag horsepower” rating they can, determining how much horsepower it will take to move a vehicle through the air at a certain mile-per-hour rate. At faster speedways teams strive to get the lowest drag number possible for higher straightaway speeds.
A strip that hangs under the front grill, very close to the ground. It helps provide downforce at the front of the car.
With the advent of radial tires with stiffer sidewalls, changing air pressure in the tires is used as another setup tool akin to adjusting spring rates in the vehicle’s suspension. An increase in air pressure raises the “spring rate” in the tire itself and changes the vehicle’s handling characteristics. If his race vehicle was “tight” coming off a corner, a driver might request a slight air pressure increase in the right rear tire to “loosen it up.”
Back Marker (top)
A car running off the pace near the rear of the field.
When a car doesn’t tend to oversteer or understeer, but goes around the racetrack as if its on rails, it’s said to be in balance.
The sloping of a racetrack, particularly at a curve or a corner, from the apron to the outside wall. Degree of banking refers to the height of a racetrack’s slope at the outside edge.
Camber addresses the angle at which a tire makes contact with the track surface. “Positive camber” indicates the angle of the tire is tilted away from the vehicle’s centerline while “negative camber” indicates the tire is tilted toward the centerline. A typical oval track setup would have positive camber in the left front and negative camber in the right front to help the vehicle make left-hand turns.
A rotating shaft within the engine that opens and closes the intake and exhaust valves in the engine.
The combination of a car’s floorboard, interior, and roll cage.
The up-and-down movement caused when a car travels around corners at high speeds. The side of the car facing the turn becomes lighter while the extra weight goes toward the outside of the turn.
The part of the tire actually touching the road.
Dirty Air (top)
The air used and discarded by the lead car.
The air pressure traveling over the surfaces of a race vehicle creates “downforce” or weight on that area. To increase corner speeds teams strive to create downforce that increases tire grip. The tradeoff for increased corner speeds derived from greater downforce is increased drag that slows straightaway speeds.
The aerodynamic effect that allows two or more cars traveling nose-to-tail to run faster than a single car. When one car follows closely, the one in front cuts through the air, providing less resistance for the car in back.
The practice of two or more cars, while racing, to run nose-to-tail, almost touching. The lead car, by displacing the air in front of it, creates a vacuum between its rear end and the nose of the following car, actually pulling the second car along with it.
The resistance a car experiences when passing through air at high speeds. A resisting force exerted on a car parallel to its air stream and opposite in direction to its motion.
Engine Block (top)
An iron casting from the manufacturer that envelopes the crankshaft, connecting rods, and pistons.
A person who specializes in creating the sheet metal body of a stock car. Most teams employ two or more.
A solid metal plate that separates the engine compartment from the driver’s compartment of a race car.
The front-most part of the race car, starting with the firewall.
A holding tank for a race car’s supply of gasoline. Consists of a metal box that contains a flexible, tear-resistant bladder, and foam baffling. A product of aerospace technology, it’s designed to eliminate or minimize fuel spillage.
Slang term for the best route around a racetrack; the most efficient or quickest way around the track for a particular driver. The “high groove” takes a car closer to the outside wall for most of a lap, while the “Low groove” takes a car closer to the apron than the outside wall. Road racers use the term “line.” Drivers search for a fast groove, and that has been known to change depending on track and weather conditions.
Slang term for the last official practice session held before an event. Usually takes place the day before the race and after all qualifying and support races have been staged.
Generally, a race car’s performance while racing, qualifying, or practicing. How a car handles is determined by its tires, suspension geometry, aerodynamics, and other factors.
The time-distance between two cars. Referred to roughly in car lengths or precisely in seconds.
Lapped Traffic (top)
Cars that have completed at least one full lap less than the race leader.
Also referred to as “free” or “oversteer.” A condition created when the back end of the vehicle wants to overtake the front end when it is either entering or exiting a turn. In qualifying mode, teams walk a fine line creating a setup that “frees the vehicle up” as much as possible without causing the driver to lose control.
Also referred to as “loose stuff.” Bits of rubber that have been shaved off tires and dirt and gravel blown to the outside of a corner by the wind created by passing vehicles comprise the “marbles” often blamed by drivers for causing them to lose control.
A term drivers use when referring to how their car is handling. When a car is neither loose nor pushing (tight).
Pit Road (top)
The area where pit crews service the cars. Generally located along the front straightaway, but because of space limitations, some racetracks sport pit roads on the front and back straightaways.
The area along pit road designated for a particular team’s use during pit stops. Each car stops in the team’s stall before being serviced.
The foremost position on the starting grid, awarded to the fastest qualifier.
Also referred to as “tight” or “understeer.” A condition that occurs when the front tires of a vehicle will not turn crisply in a corner. When this condition occurs, the driver must release the throttle until the front tires again grip the track.
The sheet metal on both sides of the car from the C-post to the rear bumper below the deck lid and above the wheel well.
The section of a race car that begins at the base of the rear windshield and extends to the rear bumper. Contains the car’s fuel cell and rear suspension components.
An aluminum plate with four holes drilled in it placed between the base of the carburetor and the engine’s intake manifold. The plate is designed to reduce the flow of air and fuel into the engine’s combustion chamber, thereby decreasing horsepower and speed.
Flaps sections at the rear of a race vehicle’s roof designed to activate, or flip up, if the air pressure flowing across them decreases. A vehicle spun backwards creates an uninterrupted airflow that causes lift. Roof flaps are designed to disrupt that airflow and keep the vehicle on the ground.
Making chassis adjustments utilizing the race car’s springs. A wrench is inserted in a jack bolt attached to the springs, and is used to tighten or loosen the amount of play in the spring. This in turn can loosen or tighten the handling of a race car.
Tuning and adjustments made to a car’s suspension before and during a race.
Racetracks less than one mile in length.
The period that begins during the latter part of the current season, wherein some teams announce driver, crew, and/or sponsor changes.
Also referred to as a “blade.” The spoiler is a strip of aluminum that stretches across the width of a race vehicle’s rear decklid. It is designed to create downforce on the rear of the vehicle, thereby increasing traction. The tradeoff is more downforce equals more aerodynamic drag, so teams attempt, particularly on qualifying runs, to lay the spoiler at as low an angle as possible to “free up” their vehicles for more straightaway speed.
Stagger is a concept that has largely been eliminated with the use of radial tires. It refers to the difference in tire circumference between the left- and right-side tires on the vehicle. Typically, the left-side tires would be a smaller circumference than the right-side tires to “help” the vehicle make left-hand turns.
New tires. The name is derived from the manufacturer’s stickers that are affixed to each new tire’s contact surface.
A penalty usually assessed for speeding on pit road at the appropriate speed and stopped for one full second in the team’s pit stall before returning to the track.
A racetrack of one mile or more in length.
Sometimes called an “antiroll bar.” Used to resist or counteract the rolling force of the car body through the turns.
A device used to check the body shape and size to ensure compliance with the rules. The template closely resembles the shape of the factory version of the car.
Also known as “understeer.” A car is said to be tight if the front wheels lose traction before the rear wheels do. A tight race car doesn’t seem able to steer sharply enough through the turns. Instead, the front end continues through the wall.
Looking at the car from the front, the amount the tires are turned in or out. Imagine your feet to be the two front tires of a racecar. Standing with your toes together would represent toe-in. Standing with your heels together would represent toe-out.
Also referred to as a “Panhard bar.” This bar locates the vehicle’s rear end housing from left to right under it. In calibrating the vehicle’s “suspension geometry,” raising or lowering the track bar changes the rear roll center and determines how well it will travel through the corners. During races, this adjustment is done through the rear window using an extended ratchet. Typically, lowering the track bar will “tighten” the vehicle and raising the track bar will “loosen” it.
A rear suspension piece holding the rear axle firmly fore and aft yet allowing it to travel up and down.
A racetrack that has a “hump” or “fifth turn” in addition to the standard four corners. Not to be confused with a triangle-shaped speedway, which only has three distinct corners.
Air that trails behind a race car and disrupts the flow of air to the cars behind it.
Also referred to as “front air dam.” This is the panel that extends below the vehicle’s front bumper. The relation of the bottom of the valance, or its ground clearance, affects the amount of front downforce the vehicle creates. Lowering the valance creates more front downforce.
Sometimes called the “winner’s circle.” The spot on each racetrack’s infield where the race winner parks for the celebration.
Refers to the relationship from corner to corner of the weight of the race vehicle. Increasing the weight on any corner of the vehicle affects the weight of the other three corners in direct proportion. Weight adjustments are made by turning “weight jacking screws” mounted on each corner with a ratchet. A typical adjustment for a “loose” car would be to increase the weight of the left rear corner of the vehicle, which decreases the weight of the left front and right rear corners and increases the weight of the right front. A typical adjustment for a “tight” vehicle would be to increase the weight of the right rear corner, which decreases the weight of the right front and left rear and increases the weight of the left front.
The practice of shifting a car’s weight to favor certain wheels.
A structure used by race teams to determine the aerodynamic efficiency of their vehicles, consisting of a platform on which the vehicle is fixed and a giant fan to create wind currents. Telemetry devices determine the airflow over the vehicle and its coefficient of drag and downforce.
NASCAR Point System (top)
Finishing last in a NASCAR race isn’t as bad as it might seem. Everyone gets a piece of the action. Points are awarded to every driver who competes in a NASCAR race.
The winner of a NASCAR race pockets 175 points. From there the points given decline in five-point increments for places two through six, and points awarded drop four points per driver for positions seven through 11, and three-point increments separate drivers’ points for finishers in 12th place or lower. It goes like this: 2nd place: 170 points; 3rd place: 165 points; 4th: 160 points; 5th: 155 points; 6th: 150 points; 7th: 146 points; and so on.
NASCAR Money (top)
Each race carries a purse figure, or its “posted awards.”
The purse is comprised of a number of segments, including: racing purse; television awards; car owner special award plans, including the Winner’s Circle Program; and a list of qualifying and special awards that may or may not be paid depending on the eligibility of the driver finishing in the appropriate position.
The racing purse breakdown designates a set amount for positions 1-43 that decreases on a sliding scale. “Television Awards” are also posted for each position, using the same sliding scale from first to 43rd.
Most manufacturers’ and special award prizes are contingent on using the products and displaying uniform patches or decals.
At certain events special prizes are awarded to the leader of each lap in the race.
About 75 percent of the posted awards are paid after each event, per the official NASCAR race report. The balance of the posted awards is the “Manufacturer’s Point Fund Awards,” a prorated share of nearly $15 million in manufacturer and sponsor funds distributed at the end of the season. While a certain portion of each purse is guaranteed to be paid after the event, some of the cash is what formerly was referred to as Studebaker money, placed in the purse simply for appearance sake.
The term “Studebaker” refers to money offered on a purse, say “$10,000 to the winner if he is driving a Studebaker.” The $10,000 would be reflected in the total posted awards, making them more impressive, but the chance of a Studebaker winning would be miniscule.
NASCAR trivia (top)
On straight-aways at 200 mph, NASCAR drivers in one second travel 293 feet—almost the length of a football field.
On turns, NASCAR drivers can experience 3 Gs of force against their bodies—comparable to the forces pressing down on shuttle astronauts at liftoff.
Research shows fit drivers are better able to handle G-forces while muscle mass offers more protection in a wreck.
Temperatures in the car often exceed 100 degrees, reaching as much as 170 degrees by the floorboards.
Drivers can lose 5-10 pounds in sweat during a race.
If a driver loses more than 3 percent of his body weight in sweat and doesn’t replace those fluids, focus, and reflexes start declining.
In a race, a NASCAR driver maintains the same heart rate—120-150 beats per minute for 3-plus hours—as a serious marathon runner for about the same length of time.
A study in anticipatory timing found racecar drivers possess the same ability to anticipate what was going to happen as a hockey goalie or a quarterback.
SAFER barriers, which NASCAR has installed at most tracks, reduces crash impacts on drivers by 70 percent or more. SAFER stands for “Steel and Foam Energy Reduction.”
No driver has died in a crash since NASCAR began requiring head-and-neck restraints in 2001.
Jerry Nadeau recorded the hardest crash—128 Gs at Richmond International Speedway in May 2003—since NASCAR began putting black boxes in cars in 2001.