Racing 101

The Basics
Timing Method
ET and handicapped racing
Dial-Ins
Reaction Time
Breakouts and other disqualifications
Who can compete

DRAG RACING 101

A drag race is an acceleration contest from a standing start between two vehicles over a measured distance. The accepted standard for that distance is either a quarter mile (1320 feet), or an eight mile ( 660 feet ). A drag racing event is a series of such two car, tournament style eliminations. The losing vehicle in each race is eliminated, and the winning drivers progress into succeeding rounds of competition. This series of races continues until one winning driver remains.These contests are started by means of an electronic device commonly called a “Christmas Tree” because of its multicolored staging lights. On each side of the tree are seven lights; two small amber lights at the top of the fixture, followed in descending order by three larger amber bulbs, a green bulb, and a red bulb.

1. Pre-stage indicator lights: Small amber bulbs warn drivers that they are approaching the starting line and the staged position. These bulbs are illuminated when the front tires of the car interrupt a light beam that crosses the lane.
2. Stage indicator: This signals to the driver that he is on the starting line and ready to run.
3. Three amber starting system: All three large amber lights flash simultaneously before the green light comes on for a Pro start. Racers running in handicap-start categories get a countdown until the green comes on.
4. Green light: Once the green light flashes, the driver is free to make his/her run. Any time that the green light is shown in a racer’s lane indicates that a fair start was accomplished.
5. Red light When the front wheels of the car leave the starting line before the green light flashes, or if a driver stages so deep that he/she crosses the starting line , the red light will shine. It indicates that the driver in that lane is disqualified.

race-tree-281x300

Two light beams cross the starting-line area and connect to trackside photocells, which are wired to the Christmas Tree and the electronic timers in the control tower. When a cars front tire breaks the first light beam, called the pre-stage beam, the pre-stage light is illuminated on the christmas tree to indicate to the racer that he or she is approximately seven inches from the starting line.

When the racer rolls forward into the stage beam, the front tires are exactly positioned on the starting line and the stage bulb is lit on the tree, indicating to both racers and to officials that the car is ready to run. When both cars are fully staged, the starter will activate the tree and the drivers will turn their attention to the three large amber lights that dominate the center of the christmas tree.

Depending on the type of racing, the christmas tree either will flash all three large amber lights simultaneouly, followed four-tenths of second
later by the green light (called a Pro Tree), or will light the three bulbs consecutively five-tenths of a second apart, followed five-tenths of a second later by the green light (a full tree).

If a driver and/or his car react too quickly and the car leaves the starting line before the green light flashes, the red foul light will illuminate, signaling disqualification.

TOP


Timing methods

Two seperate performances are monitered for each run: the elapsed time and the speed. Upon leaving the staging beams, each vehicle activates an elapsed time clock which is stopped when the same vehicle reaches the finish line. The start to finish clocking is the vehicles elapsed time (E.T.), which serves to measure performance. Speed is measured in a 66-foot “speed trap” that ends at the 1/8 mile mark and the finish line. Each lane is timed independently.

1. Pre-staged beam:A light-source-to-photocell connection (one per lane) triggers the prestage beam when the driver is approximately seven inches from the starting line.2. Stage beam: The beam controls the final staging and timing in each lane. A race cannot be started until both racers are fully staged.3. Interval timers:A secondary timing system, with beams located at 60, 330, 660, and 1000 feet, records E.T.s for the racers benefit. A 66-foot speed trap also is set at the 660-foot mark.4. Speed trap and E.T. time-clock beams:The first of these beams is located at 66 feet before the finish line and is used to trigger the speed trap clocks. A second beam, located at the finish line, shuts off both the speed and elapsed time clocks in addition to triggering a win indicator.

TOP

lights


E.T. and handicapped racing

This is where 85% of all racers are now and where 100% started out.Though some racers choose to race vehicles built to certain specifications to fit into a certain NHRA class (outlined in the NHRA rulebook), an evergrowing number of racers chooses to race on a local level in categories (or brackets) divided according to elapsed time , such as 0 to 9.99 seconds, 10.00 to 13.50 seconds, and so on. This form of racing offers a good starting point for the novice. However, thousands of drag racers enjoy E.T. racing so much that they have participated for many years.

Anytime two vehicles of different performance potentials race, they can do so evenly with handicap start. The anticipated elapsed times – referred to as a “dial-in” – for each vehicle are compared and the slower car receives a head start equal to the difference. The winner is the first car to the finish line without exceeding the dial-in.

TOP


Dial-ins

For example, car A has been timed at 15.98, 16.02 and 15.99 seconds for the quarter-mile, and the driver decides that a dial-in of 16.00 is appropriate. Meanwhile, the driver of car B has recorded elapsed times of 13.47, 13.52, and 13.56 on the same track and he has opted for a dial-in of 13.50. Accordingly, car A will get a 2.5 second head start over car B when the christmas tree counts down to each cars starting green light. This puts the emphasis on driver reaction.Because the lanes are timed independantly and the elapsed time clock does not begin ticking until the vehicle moves, if both vehicles should run exactly on their dial-ins, the win will go to the driver who reacted quickest to the starting signal. that reaction to the starting line signal is called reaction time.

TOP


Reaction times

Reaction times are measured in thousandths of a second. The reaction time counter begins when the last yellow flashes on the Christmas Tree and stops when the race car clears the stage beam. (Although some reaction timers begin counting when the green light flashes, this is not the case in the majority of starting systems.) A perfect start – one in which the race car clears the beam at the very instant the green light flashes – will produce a .400 reaction time on a Pre Tree and a .500 on a full tree (the difference is due to the length of time between the final yellow light and the green light in the two sequences.) Reaction time also measure the amount of a red light violation. For example, if a pro Tree car leaves the starting line with a .390 reaction time (or .490 on a full tree), the driver will have fouled by .010 of a second.Technique in staging and starting is one of the most vital skills of a E.T. racer because a majority of races are won or lost on the starting line.

A driver with a quicker reaction time can overcome an opponent’s perfomance advantage – whether it’s in a heads up race or if the opponent runs closer to his/her dial-in – and record the win. Beacause of this the vehicle may sometimes appear to have a mathematical advantage in comparative elapsed times but actually lose the race. This fact makes starting line reflexes extremely important in drag racing. Close observation and lots of practice pays off.

TOP


Breakouts and Other Disqualifications

Should a driver go quicker than their predetermined E.T. dial-in, it’s a breakout, and grounds for disqualification. In the case of both vehicles running under their dial-ins, the win gos to the driver that runs closest to his/her dial-in. If both drivers violate their dial-ins by an equal amount, the winner is the driver who crossed the finish line first, which will also be the driver with the quickest reaction time at this point.Other disqualifications include leaving the lane boundry (either by crossing the centerline, touching the wall or the guardrail or striking a track fixture, such as photocells.), failure to stage, and failure to pass a post-run inspection (in NHRA class racing, usually this consists of a check of vehicle weight and fuel after each run and a complete engine teardown following an event victory).

The NHRA employs a “first or worst” rule for disqualifications. A red light is considered worse than a breakout; crossing a lane boundary is worse than a red light, even though it may have occured after the red light; and all technical disqualifications supersede any on track disqualifications.

TOP


Who can compete?

Virtually anyone can compete in E.T. drag racing. Drivers are required to have valid state drivers license or NHRA competition license, and the vehicle must meet basic saftey criteria (i.e. have good brakes, be equiped with seatbelt and so on). This applies to most street type vehicles.Faster, all-out race cars must meet more stringent requirements as in outlined in the NHRA rulebook.

TOP