Drag racing

Drag racing is a competition in which vehicles compete to be the first to cross a set finish line, usually from a standing start, and in a straight line. First gaining popularity in the USA after World War II, the sport steadily grew in popularity and spread across the globe. By 2009, there were hundreds of dragstrips in operation, mainly in developed countries. Most drag races begin with a standing (stationary) start and are just 1/4 mile long (1,320 ft (400 m)). Races last between 3.9 and 17 seconds, with finishing speeds ranging from 80 to over 330 mph (530 km/h), depending upon the type of vehicle being used. The faster vehicles then need a parachute to slow down, an innovation credited (indirectly) to cartoonist Tom Medley.

Basics of drag racing
Before each drag race (also known as a pass), each driver is allowed to perform a burnout (which heats the tires and lays rubber down at the beginning of the track, improving traction). Each driver then lines up (or stages) at the starting line. Informal drag races can be started by any means, including flag-waving and arm-dropping. These methods are more likely to be seen in an un-professional setting, being most popular with illegal street racing. Professional drag races are started electronically, with a series of vertically-arranged lights known as a "Christmas tree" or just "tree". A "Christmas tree" consists of a column of lights for each driver/lane. In each column, the top two lights are small amber lights connected to light beams on the track, which when broken by the vehicle's front tire(s) indicate that the driver has pre-staged (approximately 7 in from the starting line) and then staged (at the starting line).

Below the staging lights are three 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 .4 seconds later by the green light (a pro tree), or the ambers light in sequence from top to bottom, .5 seconds apart, followed .5 seconds later by the green light (a sportsman tree, or full tree). If the driver breaks the starting line beam before the green light illuminates, the red light for that driver's lane illuminates instead, indicating disqualification.

Some cars rely on traction bars to prevent the torque from twisting the axles under heavy acceleration, transferring the torque onto the whole body. Also, some cars rely on wheelie bars to keep the front end from lifting too far off the pavement and wasting energy that would otherwise propel the car forward. On front-wheel-drive cars, these are used not to prevent wheelstanding, but to pre-load more weight onto the front wheels, increasing traction.

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. Top Fuel Dragsters and Funny Cars are now running 330 mph (530 km/h) in a quarter-mile [1,320-foot (400 m)] race.

The winner is the first vehicle to cross the finish line (and therefore the driver with the lowest total reaction time + elapsed time) without breaking out (going faster than a dial-in) or redlighting. 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. 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. 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, having left later. 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 has 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 equipment (turbocharger, supercharger, or nitrous oxide) are employed, vehicle type (such as car, truck, or motorcycle), 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 apply at once.)

North America
The National Hot Rod Association (NHRA) oversees the majority of drag racing events in North America. The next largest organization, Feld Entertainment'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, 1/4-mile nationally-recognized tracks (although the two fuel classes have 304.8-metre (1,000 ft) races because of safety issues), while the IHRA is a favorite of smaller 1/8-mile [201.2-metre (660 ft)] local tracks (and offers selected races on their national tour under the 1/8-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 500-cubic-inch (8.2 L) restriction in the IHRA's Pro Stock category) and less expensive to be associated.

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).

United Kingdom
The British Hot Rod Association (BHRA) was established in 1960, with the intent of unifying local clubs and holding organised Drag Races at disused airfields like Duxford and Graveley.

Australia
The first Australian Nationals event was run in 1965 at Riverside raceway, near Melbourne. The Australian National Drag Racing Association (ANDRA) was established in 1973, and today they claim they are the “best in the world outside the United States”.

Europe
Drag racing was imported to Europe by American NATO troops during the Cold War. Races were held in West Germany beginning in the 1960′s at the airbases at Ramstein and Sembach.

Other nations
Organized drag racing is rapidly growing in India. Autocar India organised the country’s first drag race meet in Mumbai in 2002.

Drag racing is gaining popularity in Pakistan too, with private organizations organizing such events. Bahria Town housing project organized drag race event in Rawalpindi very recently.

Organized drag racing in Colombia is Club G3's responsibility, which is a private organization. The events take part on Autódromo de Tocancipá.

Classes
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 solely 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 typically 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. The major difference is the nitro-class distance, which is 300 meters at some tracks, although the NHRA and FIA are likely to discuss the distance change in the future.

There are currently only 5 pro classes in North America (4 NHRA, 4 IHRA), which are:
 * Top Fuel Dragster (TF/D) (NHRA and IHRA). The rail dragsters, or "diggers," the fastest class—up to 90% nitromethane fuel is used.
 * Top Fuel Funny Car (TF/FC) (NHRA and IHRA) Nearly as fast as the diggers, the "floppers" (marginally) resemble actual cars. IHRA will be bringing back Top Fuel Funny Car in 2006, and Top Alcohol Funny Car (A/FC) is already a pro category in IHRA.
 * Pro Modified (Pro Mod) Some engine restrictions, very high power. Cars can run superchargers, turbochargers, or nitrous oxide. Cars running blowers are limited to 527-cubic-inch (8.64 L) while cars with nitrous can run up to 740 cubic inches (12.1 L).
 * Pro Stock (NHRA and IHRA) Must maintain a relatively stock appearance. NHRA engines can be no more than 500-cubic-inch (8.2 L) displacement while IHRA cars can run a maximum of 820 cubic inches (13.4 L) (called "Mountain Motors"). Both classes require the motors to be naturally aspirated.
 * Pro Stock Bike (NHRA and ANDRA) Heavily modified motorcycles.

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).
 * Top Alcohol Dragster
 * Competition Eliminator
 * Pro FWD
 * Super Comp/Quick Rod
 * Super Gas/Super Rod
 * Super Street/Hot Rod
 * Super Stock
 * Stock
 * Sport Compact
 * Top Sportsman (NHRA and IHRA)
 * Top Dragster (NHRA and IHRA) In NHRA, these two classes are sometimes run together as Top Comp
 * Top Fuel Funny Bike (high performance 5 second bikes)
 * NHRA and ANDRASummit Racing series Super Pro, Pro, and bike.
 * Junior Dragster (racers between the ages of 8 and 18 may race a half scale version of the sport's fastest car, Top Fuel Dragster. Juniors run as following: 12.90-slower for 8-9 year olds, 10-12 year olds at 8.90, and 13-18 year olds 7.90 and slower at a top speed of 85 mph)
 * NHRA new class for Juniors is JR COMP running 6.90s at a top speed of 110 miles per hour (180 km/h).

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 tree accordingly. The slower car will then get a head start equal to the difference in the two dial-ins, so 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 1/4 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.

Drag racing performance facts
The fastest top fuelers can attain terminal speeds of over 530 km/h (329 mph) while covering the quarter mile (402 m) distance in roughly 4.45 seconds. Top Fuel dragsters are the fastest accelerating manned vehicles on Earth, quicker even than the space shuttle launch vehicle or catapult-assisted jet fighter. A Top Fuel dragster produces 8,000 horsepower (6,000 kW) and can go from 0 to 320 mph (510 km/h) in under 5 seconds and from 0-100 km/h in 0.9 seconds

As of July 2009, the world record for a 1/4 mile pass is 4.428 seconds, set by Tony Schumacher. Schumacher also holds the top speed record for the quarter mile at 336.15 miles per hour (540.98 km/h), set in Hebron, Ohio, that same year. Top Fuel races are now held over a 305 metres (1,001 ft) distance for safety reasons (but still held on 400m lengths in Australia). The record under the new rules is also held by Tony Schumacher at 3.771 seconds, and the top speed record is held by Larry Dixon at 321.58 miles per hour (517.53 km/h).

Drag racing rules require a record run be backed up within one percent at the same meet in order to count as a record; hydrogen peroxide rocket dragsters such as Sammy Miller and Kitty O'Neil's 3.22 ET and 412-mile-per-hour (663 km/h) quarter mile world records set in 1977 are not official because they failed to back up those runs within one percent, per NHRA and FIA rules. .

In fact, a vehicle traveling at a steady 200 miles per hour (320 km/h) as it crosses the starting line will be beaten to the finish line by a top fuel dragster starting from a dead stop at the same moment. Additionally, through the use of large multiple braking parachutes, the astounding performance of 0 to 330 miles per hour (530 km/h) and then back to 0 in 20 seconds can be obtained. Using twin drag parachutes, deceleration of up to 5 G can be attained, enough to cause detached retinae. The legendary Don Garlits, holder of multiple records, had to retire because of a detached retina.

The faster categories of drag racing are an impressive spectacle, with engines of over 8,000 horsepower (6,000 kW) 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 substance to increase traction) to get optimum grip on the all-important launch.

The blown alcohol and nitrous oxide-injected Pro Modifieds (or Pro Mods) with their 1500 kW (2012 hp) engines are capable of running in the low six second range at over 230 miles per hour (370 km/h). IHRA Pro Stocks are just behind, running in the 6.3 second range at over 215 miles per hour (346 km/h), while NHRA Pro Stocks run in the high sixes at over 200 miles per hour (320 km/h). Top Sportsman and Top Dragster, the two fastest sportsman classes, run a bracket style race and can range from high sevens at over 170 miles per hour (270 km/h) to 6.4s at 210 miles per hour (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 miles per hour (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 respectively, both with a throttle stop.

Another class of car is the Sport Compact class that use their power to weight ratio to get performance. 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 clock 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 500 cubic inches (8.2 L) 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 MOPAR (Chrysler, Dodge, Jeep, Plymouth), 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.

Other classes have also declined or disappeared. NHRA has banned the notorious AA/FA, or Fuel Altered, though it continues to be seen in nostalgia racing. The Fiat Topolino was the first to be used this way, in followed by the more conventional modified VW Beetle.

Drag racing strategies and methods
The various strategies used in drag racing begin with the car itself. Performance enhancements must comply both with NHRA/IHRA rules and restrictions based on the class the car is running in. Some common enhancements include the use of slicks (smooth, soft tires that grip the track), methods for introducing more air into the motor such as turbochargers, superchargers, and nitrous oxide, specialized fuels (higher octane gas, methanol, and so on), improved suspensions, and a multitude of others.

The burnout
When approaching the starting line (also known as the staging area), most racers will perform a burnout − that is, apply water 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 utilize a solenoid valve (which can be toggled on and off) called a "line-lock", which is mandatory in many classes. In rear wheel drive operation: the brake pedal is depressed, the line lock is activated, the brake pedal is released and as long as the line lock is depressed brake pressure will remain in only the front brake calipers. This allows the car to remain stationary 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.

Staging
After the burnout comes staging, where the cars pull up to the starting line. Each lane has its own string of lights on the “Christmas tree,” with two small orange lights on top. These are the prestaged and staged lights. The two cars will slowly creep forward until the first (pre-staged) orange light is lit. This means they are very close to the actual starting line (a mere 7 in (18 cm)). Then the cars will nudge forward until the second (staged) light is lit. This indicates they are at the starting line, this is the point where the driver will apply the line-lock to prevent the car from rolling while she/he uses the clutch and gas pedals. When both cars have lit both bulbs, the starter will engage the Christmas tree. If the racer moves too far the top bulb will go out and the driver is said to have deep-staged. While some drivers prefer this technique, some tracks and classes prohibit it. An advantage can be had, by deep-staging, in gaining a quicker reaction time (RT) but at the expense of the elapsed time (ET) and MPH achieved at the top end of the track; there is also a higher risk of "red-lighting." A loose etiquette is followed when staging. The driver to illuminate the first light will wait for the second car to light both bulbs before advancing to the staged light.

The tree
Once the competitors have both staged, the starter presses a button to start the race. Races starts are signaled with a “Christmas tree”, which consists of two columns of lights− one for each racer. There a number of yellow lights, a green light, and a red light. There are two types of tree used. The sequence varies depending on the particular class being raced, but typically, each yellow lights 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.

The race
Several things are important on the way down the track in drag racing. The first is not to cross into the opponent's lane, as this will result in disqualification. In case of a double disqualification in which one driver commits a foul start and the second driver crosses into his opponent's lane, the driver who committed the foul start wins. Another important consideration is when to shift gears. Most drag cars are shifted manually by the driver, and there are optimum times for shifting that vary with each car. Typically, power will increase as the engine RPMs (revolutions per minute) increase, but only up to a point before power begins to taper off. The ideal time to shift is when the descending power curve for the lower gear crosses the ascending power curve for the higher gear. Most drag racers use a tachometer to judge shift points. In Fuel classes especially, "pedalling" the car (adjusting the throttle) to prevent loss of traction is often important and one measure of how good a driver is.

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 minimum elapsed time, quicker than the official break-out elapsed time; a car which posts a lower time is ejected from the event.

Historic cars

 * 1954 — first slingshot, built by Mickey Thompson.
 * 1962 — the Greer-Black-Prudhomme digger, with the best win record in NHRA history.
 * 1966 — Eliminator I, the first true Funny Car, built by the Logge brothers
 * 1971 — Swamp Rat XIV, first rear-engined dragster, built by Don Garlits; Ed Donovan introduces the 417 Donovan hemi, an aluminum copy of the Chrysler
 * 1974 — first tube chassis Pro Stock car, Bill Jenkins' '72 Vega.
 * 1986 — Swamp Rat XXX, first streamlined dragster, built by Don Garlits.