The sport of drag racing is an acceleration contest between two vehicles racing from a standing start over a straight quarter- or eighth-mile course. A drag racing event is made up of a series of individual two-vehicle races called eliminations, with competing machines divided into a variety of classes. Class eligibility is governed by criteria that limit engine size, type of fuel, vehicle weight, allowable modifications, and aerodynamics.
THE CHRISTMAS TREE
1. PRE-STAGE INDICATOR LIGHTS: Round amber bulbs warn drivers that they are approaching the starting line and the “staged” position.
2. STAGE INDICATOR LIGHTS: Signal drivers that they are on the starting line and ready for a run. These amber bulbs are turned on when the front wheels of the race vehicle interrupt the beam from a light source to the photo cells that also trigger the timing equipment when the vehicle leaves the light beams.
3. THREE-AMBER STARTING SYSTEM: All three ambers/LED lights in a driver’s lane flash simultaneously before the green light comes on. This is called a Pro start system. Racers running in handicap categories get a countdown of one amber light at a time until the green light comes on. The Pro start system runs with a .4-second difference between the amber and green lights. The handicap system runs with a .5-second difference between bulbs.
4. GREEN LIGHT: This is the one that makes it all happen. Once the green light flashes, the driver in that lane is free to make a run down the track. Anytime a green light is shown in a driver’s lane, it indicates that a fair start was accomplished.
5. RED LIGHT: When the front wheel of a vehicle leaves the starting line before the green light comes on, the red light will flash in that lane to indicate that the driver in that lane has been disqualified. During competition, only one red light will flash, thus eliminating only the first offender.
A set of lights, commonly called a “Christmas Tree,” is used at the starting line. There is a .4-second difference between the flash of all the amber lights and the flash of the green light in the Pro start system. In handicap racing, the amber lights illuminate individually, with a .5-second difference between the last amber and the green. Upon leaving the starting line, each contestant activates a timer, which is then stopped when his or her vehicle reaches the finish line. The start-to-finish clocking is the vehicle’s elapsed time (e.t.), which serves to measure performance and often to determine handicaps during competition.
Virtually anyone can compete in drag racing. Drivers must have a valid state- or government-issued driver’s license beyond a learner’s-permit level or, in some cases, an NHRA competition license and must be capable of the safe operation of the vehicle. The vehicle must meet basic safety criteria (brakes, seat belt, etc.). This applies to most street-type vehicles. Faster, all-out race cars must meet more stringent requirements as outlined throughout the NHRA Rulebook.
While some choose to race vehicles they build to certain specifications to fit into a certain NHRA class (outlined elsewhere in this Rulebook), an ever-growing number of racers choose to compete on a local level in categories divided on the basis of performance, or e.t. (elapsed time), brackets. This form of drag racing offers a good starting point for the novice wishing to become involved in the sport. Thousands of drag racers enjoy E.T. handicap racing, which allows drivers in slower cars to compete on an equal basis with drivers of quicker and faster machines. The performance predictions for all vehicles are compared, and the slower car receives an advantage at the start equal to the difference between the cars’ anticipated e.t.s. For example, a car with a dial-in of 15.75 will have a 2.5-second head start over a car with a dial-in of 13.25.
With this system, virtually any two vehicles can be paired in a competitive drag race. It is designed so that if both vehicles cover the quarter-mile in exactly the predetermined elapsed time, the win will go to the driver who reacted quickest to the starting signal. That reaction to the starting signal is called “reaction time.” Each lane is timed independently, and the clock does not start until the vehicle actually moves. Because of this, a vehicle may sometimes appear to have a mathematical advantage in comparative elapsed times but will actually lose the race. This fact makes starting-line reflexes extremely important in drag racing.
In all cases but one, the car that gets to the finish line first wins. The exception: When both cars run quicker than their dial-ins, known as a “double-breakout race,” the car closest to its dial-in is the winner. For instance, if both cars have a dial-in of 8.90 and one breaks out at 8.854 and the other at 8.864, the car that ran 8.864 wins.
Another form of disqualification is a foul start, or “red-light.” This happens when the driver reacts to the Tree too quickly and drives away from the starting line before the green go signal. Should dual infractions occur —a red-light and a breakout, for example — the driver who red-lights would be classified as committing the worse infraction and lose.
Hence, the start is key, because all races start from a standstill. Today’s modern starting system is a product of continued development, designed to provide each competitor with the fairest start possible. The Christmas Tree system features a vertical series of lights, displaying a visual countdown for each driver. Technique in staging and starting is one of the most vital skills an E.T. handicap drag racer can develop because a majority of races are won or lost at the starting line. Close observation and practice can pay off.
Two performances are monitored for each run: elapsed time and speed. The elapsed time is started when the vehicle first leaves the starting line, breaking the beam that activates the electronic timer. As the vehicle continues down the course, the timer records the elapsed seconds until the car breaks the finish-line beam and stops the timer. Speed is determined by two additional light beams at the finish line.
The wide variety of classifications in NHRA Drag Racing provides a showcase for everyone’s favorite type of car and assures excitement for fans and drivers alike, whether driven by passion for the automobile, vehicle appearance, or speed.