Prerace preparations Before each race (commonly known as a pass), each driver is allowed to perform a burnout, which heats the driving tires and lays rubber down at the beginning of the track, improving traction. The cars run through a "water box" (formerly a "bleach box", before bleach was replaced by flammable traction compound, which produced spectacular, and dangerous, flame burnouts; the hazard led NHRA to mandate use of water in the 1970s).
Prerace preparations Before each race (commonly known as a pass), each driver is allowed to perform a burnout which heats the driving tires and lays rubber down at the beginning of the track improving traction. The cars run through a "water box" (formerly a "bleach box", before bleach was replaced by flammable traction compound, which produced spectacular, and dangerous flame burnouts; the hazard led NHRA to mandate use of water in the 1970s)