E.T. bracket race

Bracket racing is a form of drag racing that allows for a handicap between predicted elapsed time of the two cars over a standard distance, typically within the three standard distances (1/8 mile, 1,000 foot, or 1/4 mile) of drag racing.

The effect of the bracket racing rules is to place a premium on consistency of performance of the driver and car rather than on raw speed, which in turn makes victory much less dependent on large infusions of money, and more dependent on mechanical and driving skill, such as reaction times, shifting abilities, and ability to control the car. Therefore, bracket racing (using the aforementioned handicapping system) is popular with casual weekend racers. Some will even drive their vehicles to the track, race them, and then simply drive them home.

This format allows for a wide variety of cars racing against each other. While traditional drag racing separates cars into a wide variety of classes based on power and weight, bracket racing classes can be simpler, and can accommodate any vehicle with basic technical/safety inspection. Race events organized in this way are sometimes called "run-what-ya-brung".

Each car chooses a dial-in time before the race, predicting the elapsed time the driver estimates it will take his or her car to cross the finish line. This is usually displayed on one or more windows so the starter can adjust the "christmas tree" starting lights accordingly. The slower car in the race is given the green light before the faster car by a margin of the difference between their two dial-in times.

In principle, if both drivers have equal reaction times and their cars run exactly their posted dial-ins, both cars should cross the finish line at precisely the same time. In reality, this is an extremely rare occurrence. Measuring devices both at the start and at the end of the track post times down to 1/100000 of a second (0.00001s precision), which makes tied races almost impossible.

Some forms of bracket racing (NHRA Competition Eliminator, NHRA Stock groups) have cars classified by type, and the dial-in time is based on the type of car that is entered.

When a car leaves the starting line, a timer is started for that car. The difference between when the green light comes on and when the car actually leaves the starting line is called the reaction time. If a driver leaves before the light turns green, he is automatically red-lighted and disqualified for that round unless the opponent commits a more serious violation (crossing a track boundary line, timing block, or touching the barrier). In a drag race event with a heads-up situation, when the first driver commits a red light foul, the green light automatically turns on for the other driver. In a handicap start, if both drivers leave ahead of the green light, the driver with the worse aggravation will have the lane subsequently charged with the foul. The winner by default is the one who performed the lesser aggravation (-0.003 wins over -0.009, for example).

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Wikipedia