Form of motor racing in which two contestants race side by side from a standing start over a straight quarter-mile strip of pavement. Winners go on to compete against others in their class until only one is left undefeated. There are three main classes of vehicle: (1) the Top Fuel Eliminator (called a “rail” or “slingshot”), a lightweight, long-chassied vehicle with wide rear tires that is fueled by a special mixture, such as methanol and nitromethane; (2) the “funny car,” a high-performance copy of a late-model production car that uses special fuel; and (3) the standard production car, a modified version of a gasoline-powered production car. The Top Fuel class is the fastest, followed by the funny car. Drag racing is most popular in the U.S.
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Drag racing is a competition in which objects compete to be the first to cross a set finish mark, usually from a dead stop, and in a straight line. The sport is primarily practiced by automobiles and motorcycles. While usually thought of as an American and Canadian pastime, drag racing is also very popular in Australia, New Zealand, Japan, the Caribbean in particular Aruba, Mexico, Greece, Malta, South Africa, the United Kingdom, and Scandinavian countries especially Finland and Sweden.Also in the Netherlands (Drachten) At any given time there are over 325 drag strips operating world-wide.
Below the staging lights are two large amber lights, a green light, and a red light. When both drivers are staged, the tree is activated to start the race, which causes the three large amber lights to illuminate, followed by the green light. There are two standard light sequences: Either the three amber lights flash simultaneously, followed 0.4 seconds later by the green light (a "Pro" tree), or the amber lights light in sequence from top to bottom, 0.5 seconds apart, followed 0.5 seconds later by the green light (a "Sportsman" or full tree). If the driver leaves the starting line before the green light illuminates, the red light for that driver's lane illuminates instead, indicating disqualification should no further infractions occur.
Several measurements are taken for each race: reaction time, elapsed time, and speed. Reaction time is the time from the green light illuminating to the vehicle leaving the starting line. Elapsed time is the time from the vehicle leaving the starting line to crossing the finish line. Speed is measured through a speed trap near the finish line, indicating the approximate maximum speed of the vehicle during the run.
The winner is the first vehicle to cross the finish line (and therefore the driver with the lowest total reaction time + elapsed time). The elapsed time is a measure of performance only; it does not, per se, determine the winner. Because elapsed time does not include reaction time, a car with a faster elapsed time can actually lose the race if the driver does not react to the green light fast enough. In practice, it is advantageous for the driver to "jump the gun" by a fraction of a second, starting the car during the split-second interval between when the yellow light goes out and the green light goes on. However, if the car leaves the front light beam before the green light comes on, the driver has "red-lighted" (because the red light is lit on the Christmas Tree) and should no further fouls happen during the race, is disqualified. Once a driver commits a red-light foul, the other driver can also commit a foul start by leaving the line too early but would win because he or she would leave the line slower. A driver who gets a substantial lead at the start is said to have gotten a "holeshot". A win where a driver wins a race with a higher elapsed time but lower reaction time is known as a "holeshot win".
It is also possible for a driver to be disqualified for other infractions, depending on the rules of the race, including crossing the centerline between lanes, touching a wall, striking a track fixture, failing to stage, failing a tech inspection, or running faster than expected/allowed for the assigned class. In boundary line violations, if the offending driver have made a clean start, and the red-light driver does not commit the violation unless forced by the offending car for safety reasons, the driver who committed a red-light foul wins.
In the common Eliminator racing format, the losing vehicle and driver are removed from the contest, while the winner goes on to race other winners, until only one is left. In cases where a driver has no opponent for a round, the driver makes a solo pass or "bye run" (in order to at least partially eliminate the advantage that would otherwise come from the engine having one less run on it) to advance to the next round. In most Eliminator formats, the bye runs take place only in the first round. On bye runs, some drivers may choose to drive slowly so as not to stress the car unduly, though choice of lane in the each round is often determined by time in the previous round, making this strategy possibly detrimental. Unlike the NHRA, many European events feature a consolation race where the losers of the semifinal rounds race for third place, the final spot on the podium, and standings points.
During drag racing events, vehicles are classified by various criteria that take into account the extent of modifications to the car. These criteria include engine capacity, configuration of cylinders, frame type, vehicle construction materials, wheelbase, horsepower to weight ratio, number of cylinders, whether or not power adding devices such as turbochargers, superchargers or nitrous oxide are employed, vehicle type (such as car, truck, et cetera), or even make and model for limited entry fields. The aforementioned divisions are in place to ensure that the cars are evenly matched during the race. (not all of these can apply)
Drag racing vehicles are special in that they are modified to be lighter and more powerful than in their standard form. A lighter vehicle means that the power-to-weight ratio is increased and hence a greater acceleration will be achieved. Power increases vary depending on the extent of the modifications to the engine.
The National Hot Rod Association (NHRA) oversees the majority of drag racing events in North America. The next largest organization, Live Nation's International Hot Rod Association (IHRA), is about one-third the size of NHRA. Nearly all drag strips are associated with one sanctioning body or the other. The NHRA is more popular with large, 1/4th mile nationally-recognized tracks (although the two fuel classes have 1,000 foot races because of safety issues), while the IHRA is a favorite of smaller 1/8th mile local tracks (and offers selected races on their national tour under the 1/8th mile format. One reason for this (among others) is the IHRA is less restrictive in its rules, such as rules on nitrous oxide (legal in Pro Modified) and oversized engines (no 8.2 liter / 500cid engine restriction in the IHRA's Pro Stock category) and less expensive to be associated, as the IHRA is part of a publicly traded company.
Prior to the founding of the NHRA and IHRA, smaller organizations sanctioned drag racing in the early years. The first commercially sanctioned drag race on the East coast was reputed to have been held at Longview Speedway (now Old Dominion Speedway) in Manassas, VA. Old Dominion Speedway is currently sanctioned by the SBRA (Southern Bracket Racing Association).
There are literally hundreds of different classes in drag racing, each with different requirements and restrictions on things such as weight, engine size, body style, modifications, and many others. NHRA and IHRA share some of these classes, but many are soley used by one sanctioning body or the other. The NHRA boasts over 200 classes, while the IHRA has fewer. Some IHRA classes have multiple sub-classes in them to differentiate by engine components and other features. There is even a class for aspiring youngsters, Junior Dragster, which uses an eighth-mile, also favored by VW racers.
In 1997, the FIA (cars) and UEM (bikes) began sanctioning drag racing in Europe with a fully established European Drag Racing Championship, in cooperation (and rules compliance) with NHRA. The major European drag strips include Santa Pod Raceway in Podington, England; Alastaro Circuit, Finland; Mantorp Park, Sweden; Gardermoen Raceway, Norway and the Hockenheimring in Germany.
However, there are only 5 pro classes in North America (4 NHRA, 4 IHRA), which are:
In addition to the professional classes, these are some other popular classes:
A complete listing of all classes can be found on the respective NHRA and IHRA official websites (see external links).
In the FIA European Drag Racing Championships a different structure of professional categories is used with Top Fuel Dragster (with a 90% nitromethane mix), Top Methanol (Alcohol) Dragster, Top Methanol (Alcohol) Funny Car, Pro Stock and Pro Modified running as professional championships as well as FIA specifications published for Fuel Funny Car although this does not run as a championship.
The UEM also has a different structure of professional categories with Top Fuel Bike , Super Twin Top Fuel Bike and Pro Stock Bike contested leaving the entire European series with a total of 8 professional categories.
To allow different cars to compete against each other, some competitions are raced on a handicap basis, with faster cars delayed on the start line enough to theoretically even things up with the slower car. This may be based on rule differences between the cars in stock, super stock, and modified classes, or on a competitor's chosen "dial-in" in bracket racing.
A "dial-in" is a time the driver estimates it will take his or her car to cross the finish line, and is generally displayed on one or more windows so the starter can adjust the starting lights on the "Christmas tree" (commonly just "tree") accordingly. The slower car will then get a head start equal to the difference in the two dial-ins, so that if both cars perform perfectly, they would cross the finish line dead even. If either car goes faster than its dial-in (called breaking out),it is disqualified regardless of who has the lowest elapsed time; if both cars break out, the one who breaks out by the smallest amount wins. This eliminates any advantage from putting a slower time on the windshield to get a head start. 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, in that victory goes to the driver able to precisely predict elapsed time, whether it is fast or slow. This in turn makes victory much less dependent on large infusions of money, and more dependent on skill. Therefore, bracket racing is popular with casual weekend racers. Many of these recreational racers will drive their vehicles to the track, race them, and then simply drive them home. Most tracks do not host national events every week, and on the interim weekends host local casual and weekend racers. Organizationally, however, the tracks are run according to the rules of either the NHRA or the IHRA (for the most part). Even street vehicles must pass a safety inspection prior to being allowed to race.
Besides NHRA and IHRA, there are niche organizations for muscle cars and nostalgia vehicles. The National Electric Drag Racing Association (NEDRA) races electric vehicles against high performance gasoline-powered vehicles such as Dodge Vipers or classic muscle cars in ¼ and 1/8 mile races. The current electric drag racing record is 7.824s for a quarter mile. Another niche organisation is the VWDRC which run a VW-only championship with vehicles running under 7 seconds. A top fuel dragster produces 8000 horsepower and can go from 0 to 320 mph in 5 seconds
The faster categories of drag racing are an impressive spectacle, with engines of over five MW (6700 horsepower) and noise outputs to match, cars that look like bizarre parodies of standard street cars (funny cars), and the ritual of burnouts where, prior to the actual timed run, the competitors cause their car's driving wheels to spin while stationary or moving forward slowly, thus heating up the tires to proper working temperature and laying down a sticky coat of rubber on the track surface (which may have been coated with VHT Trackbite or similar to increase traction) to get optimum grip on the all-important launch.
The Blown Alcohol and nitrous oxide-injected Pro Modifieds with their 1500 kW (2012 hp) motors are capable of running in the low six second range at over 370 km/h (230 mph). The IHRA Pro Stocks are just behind, running in the 6.3 second range at over 346 km/h (215 mph), while the NHRA Pro Stocks run in the high sixes at over 322 km/h (200 mph). Top Sportsman and Top Dragster, the two fastest sportsman classes, run a bracket style race and can range from high sevens at over 274 km/h (170 mph) to 6.4s at 210 mph (340 km/h). Super Comp/Quick Rod are either dragsters or doorslammers, but run with a throttle stop. Some cars can run as low as a 7.50 at around 180 mph (290 km/h) without a throttle stop, but use it in order to hit an 8.900 index. Super Gas/Super Rod and Super Street/Hot Rod run with a 9.900 and 10.900 index respectfully, but both run with a throttle stop.
Another class of car is the Sport Compact class that use their power to weight ratio to get performance. The FIAT Topolino was the first to be used this way, in the notorious AA/FA, or Fuel Altered, followed by the more conventional modified VW Beetle. A turbocharger or supercharger is very common, and often necessary to break the 12-second barrier. Cars have progressed rapidly though and can now even run seven second quarter miles.
In 2001, the NHRA bought out NIRA and renamed it the Sport Compact category featuring such cars, and while Toyota, Honda, Nissan, and Subaru are very popular, the NHRA has also permitted General Motors, Ford, and Chrysler cars to participate in Sport Compact.
With NHRA rule changes in recent years making Pro Stock cars more compact, a change from an 8.2 L (500 cubic inch) V-8 engine to a modified factory four or six cylinder double overhead camshaft engine can easily convert a Pro Stock car to Sport Compact Pro Rear Wheel Drive car. The cars are separated by performance, and since 2003 categories have been split based on the car's drive wheels. Ironically, almost all NHRA Sport Compact records for elapsed time and speed are held by General Motors and Ford cars, rather than the imports.
With the decline in sport compact drag racing in the United States, and the demise of the NOPI-NHRA sport compact series in 2008, the NHRA reclassified sport compact racing by classifying the cars within the mainstream categories, allowing the cars to race against traditional domestic cars and street rods in traditional series. Effective July 17, 2008, the NHRA permitted the upper class of sport compact racing -- Pro Rear Wheel Drive, Front Wheel Drive, Modified, and Hot Rod categories to participate in the Competition Eliminator class, while in 2009, "all motor" categories in Sport Compact will have their own class (EX) in Super Stock, allowing the cars to race against traditional drag racing cars.
When approaching the starting line (also known as the staging area), most racers will apply water (formerly thought to be bleach by spectators as it was dispensed from old bleach bottles) to the driven tires either by backing into a small puddle (the "bleach box" or "water box") or having it sprayed on. The car then exits the water and does a burnout to heat the tires, making them even stickier. Some cars have a mandatory "line-lock" which prevents the rear brakes from engaging when the brake pedal is depressed (which can be toggled on and off). This allows the car to remain stationary (with the brakes applied) without burning up the rear brake pads while doing a burnout. Cars in street classes (which must be street legal) are the only exception to this pre-race ritual, as the grooved tires tend to retain some of the water.
Once the competitors have both staged, the starter presses a button to start the race. There are two types of tree used. A sportsman tree, used for bracket and handicap racing, consists of each yellow lighting 0.5 seconds after the one above it. The green comes on 0.5 seconds after the last yellow is lit. If the race is a handicap race each side of the tree will have its own timing. A pro tree consists of all three yellows being illuminated at the same time, followed by the green 0.4 seconds later. This type of tree is used for professional and heads-up racing. It should be noted that some tracks run a Pro-style tree for bracket racing during special "Street Racing" bracket events.
Strategies for crossing the finish line usually only involve bracket racing (see above). If one car has a huge lead, it may slow down before crossing the finish line to prevent a breakout. Especially in bracket racing, it is not uncommon to see the leading vehicle's brake lights come on briefly before the finish line. The term "sandbagging" is used in races where the driver in a bracket race puts a slower "dial in" (the predicted E.T.) that he/she could run and then at the finish line tap the brakes lightly or lift of the gas pedal (also known as pedalling) to reduce the E.T. to run as close as possible to the dial in.
If both cars break out, the car closer to their dial-in wins. In NHRA Junior Dragster racing, however, there is a mimimum elapsed time, quicker than the official break out elapsed time; a car which posts a lower time is ejected from the event.