When following another vehicle closely, aerodynamics causes the car(s) behind to lose downforce on the front end causing the car to not turn as well through the corners (push).
AIR PRESSURE
Another way of changing a car's handling is by increasing or decreasing the amount of air in one or more tires. If a car is "tight," adjusting the air pressure up in the right rear tire may help.
CAMBER
The angle at which the tire makes contact with the track.
DOWNFORCE
The aerodynamic pressure traveling over the surfaces of a race vehicle creates weight on that area and makes the tires grip better.
LOOSE
Also known as "free." A condition of the race car where the back tires have a tendency to slide outwards, causing the back end to want to lose traction and hit the wall.
MARBLES
Bits of rubber and other debris which is blown up the racetrack by the wind from the racecars. Causes a car to lose traction if up in the "marbles."
PUSH
Also known as "tight." A condition where the front tires of the racecar lose grip while cornering. This causes the car to try to head up into the wall.
RESTRICTOR PLATE
An aluminum plate placed between the carburetor and intake manifold with four holes drilled in it, designed to reduce horsepower and speed. Used only on superspeedways.
ROOF FLAPS
Sections at the rear of a racecar's roof that flip up if the air pressure flowing across them decreases. Tends to keep the racecar from getting airborne during wrecks.
SPOILER
A strip of aluminum across the rear decklid designed to create downforce on the rear of the vehicle.
TRACK BAR
This locates the vehicle's rear end housing from left-to-right under it. Another way of adjusting the handling.
VALANCE
This is the panel that extends below the vehicle's front bumper. Lowering the valance creates more front downforce.
WEDGE
Refers to the relationship from corner-to-corner of the weight of the race vehicle. Yet another way to adjust a car's handling.
WIND TUNNEL
Used by race teams to determine the aerodynamic efficiency of their vehicles.
What do the flags mean?
Green Flag
Racing has started or restarted.
White Flag
One lap to go in the race.
Checkered Flag
The race is over!
Black Flag
The car this flag is shown to has violated the rules and needs to make a pit stop.
Blue/Yellow Flag
Shown to a car that is being lapped telling them to move over for the leaders. Used more at dirt tracks than in Winston Cup.