Drag Strip Timing and Scoring System Layout

PRE-STAGED BEAM:
An infrared beam sender/receiver connection (per lane) triggers pre-staged lights and signals drivers that they are close to "staging" when this beam is broken by vehicle's front wheel.

STAGED BEAM/STARTING LINE:
This infrared beam sender/receiver connection controls the starting and timing of each race. This beam triggers an independent "lane timer" for elapsed time and will trigger the red foul light if a false start occurs. A race cannot be started until both competitors are fully "staged." The staged beam is 6 inches past the pre-staged beam.

INTERVAL TIMERS:
Time and speed are recorded at five intervals along the track. There are clocking devices at the 60-foot, 330-foot, 1/8-mile, 1,000-foot and 1/4-mile locations.

SPEED TRAPS AND ELAPSED-TIME CLOCK BEAMS:
The first of these infrared beam sender/receiver triggers is located 66 feet before the finish line and is used to start the individual lane top speed clocks. A second beam, located at the finish line, shuts off both the individual lane elapsed-time and top speed clocks, and triggers the win indicator. The 66-foot speed trap com-putes top speed.

The length of the actual racing surface at an NHRA Drag Racing Series event is one-quarter mile, or 1,320 feet. The average width of each lane is 30 feet.