A racing dictionary

By Times staff writer
Published March 30, 2007

Backmarker: A car at or near the back of the field.

Banking: The sloping of the track surface, measured in degrees from horizontal.

Caution: A period of a race when the field is required to slow behind the pace car, and passing is not allowed. Cautions result from an accident, an oil leak, rain or other trouble on the track.

Chassis: The frame and suspension of a car.

Downforce: The aerodynamic pressure pushing the car down on the track.

Drafting: A driver's use of the car ahead of him or her to break wind resistance and gain momentum.

Grip: Tire traction on the track.

Groove: The best route around the racing surface.

HANS: The Head and Neck Safety device, which became famous after Dale Earnhardt's death at Daytona. The brace fits around the shoulders and attaches to a driver's helmet, limiting neck movement during a crash to help minimize whiplash.

Happy hour: The final hour of practice during which faster laps often occur because the track is cooler.

Loose: A car is loose when the rear is unstable because of improper rear tire grip. Also known as oversteer.

Marbles: Small pieces of tire rubber that build up above the racing groove.

Pushing: The car resists turning because of a lack of grip. Also known as understeer.

Slick: A condition in which tires have trouble gripping the track, but is not limited to oil or water. Also refers to a grooveless tire.