Drag racing

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Contents 1 Headline text 2 Basics of drag racing 2.1 Four cylinder vehicles 2.2 Six cylinder vehicles 2.3 Eight cylinder vehicles 2.4 Other engine types 3 Drag racing in the 21st century 4 Racing organization 5 Drag racing performance facts 6 Drag racing strategies and methods 6.1 The burnout 6.2 Staging 6.3 The nitrous purge 6.4 The race 7 Glossary 8 References 9 External links 10 Wikis

[edit] Headline text

Drag racing is a form of auto racing in which any two vehicles (most often two cars or motorcycles) attempt to complete a fairly short, straight and level course in the shortest amount of time, starting from a dead stop. Drag racing originated in the United States and is still the most popular there. The most common distance is one quarter mile (402 m / 1320 ft.), although one-eighth of a mile (201 m / 660 ft.) tracks are also popular. The dragstrip extends well beyond the finish line to allow cars to slow down and return to the pit area.

While usually thought of as an American and Canadian pastime, drag racing is also very popular in Brazil, Australia, New Zealand, Japan, the Caribbean (in particular Aruba, Mexico, Greece, Malta, South Africa and most European and Scandinavian countries especialy Finland and Sweden. At any given time there are over 325 drag strips operating world-wide.

[edit] Basics of drag racing

Drag racing usually involves two cars racing each other over a set distance, usually 1/4 mile. Although distances range from two hundred meters to one kilometer, the four-hundred metre drag race is the most popular. Races of this nature test a vehicle in terms of acceleration and top speed, as well as the driver with regard to skill and concentration. Although the driver does not have any turns to negotiate or opponents to defend against, apart from the competitor in the other lane, he or she must be very accurate with gear shifting and throttle modulation.

During drag racing events, vehicles are classified into different divisions 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.

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 table below illustrates some common outputs for different induction configurations for a typical drag-racing vehicle. Please note that the numbers expressed are not by any means limits for power, but they're rather accurate indications of typical levels of power produced by daily driven drag racing vehicles.

[edit] Four cylinder vehicles

• Normally aspirated 4 cyl. engine* (typical) = 65 horsepower-300 horsepower [50kW-170kW]
• Turbocharged 4 cyl. engine* (typical) = 170 horsepower-400 horsepower [127kW-300kW]
• Supercharged 4 cyl. engine* (typical) = 120 horsepower-270 horsepower [90kW-202kW]
• Nitrous oxide may be added to any one of these engine configurations. Nitrous oxide will produce different levels of added power depending on mechanical considerations. For instance: A nitrous oxide injection setup will add far more power to a vehicle equipped with a turbocharger, but lacking an intercooler/aftercooler, than a vehicle with an intercooler/aftercooler due to adiabatic efficiency considerations. Adding nitrous oxide can produce as little as a ten horsepower addition, or as much as three-hundred to five-hundred horsepower in some high-performance applications.

[edit] Six cylinder vehicles

• Normally aspirated 6 cyl. engine* (typical) = 120hp-300hp [90kW-225kW]
• Turbocharged 6 cyl. engine* (typical) = 220hp-550hp [165kW-410kW]
• Supercharged 6 cyl. engine* (typical) = 145hp-450hp [108kW-335kW]
• Nitrous oxide may be added to any one of these engine configurations. Nitrous oxide will produce different levels of added power depending on mechanical considerations. For instance: A nitrous oxide injection setup will add far more power to a vehicle equipped with a turbocharger, but lacking an intercooler/aftercooler, than a vehicle with an intercooler/aftercooler due to adiabatic efficiency considerations. Adding nitrous oxide can produce as little as a ten horsepower addition, or as much as three-hundred to five-hundred horsepower in some high-performance applications.

[edit] Eight cylinder vehicles

• Normally aspirated 8 cyl. engine* (typical) = 190hp-550hp [140kW-410kW]
• Turbocharged 8 cyl. engine* (typical) = 485hp-1000hp [360kW-746kW]
• Supercharged 8 cyl. engine* (typical) = 350hp-765hp [260kW-570kW]
• "Top Fuel" 8 cyl. engine (typical) = 5,500hp+ (these are 500 cubic inch V8 Hemi Engines running on a mix of 95% Nitro Methane to 5% petrol - they produce phenomenal power and propel the vehicle to speeds of over 300mph (500+kmh) in under 5 seconds.

• Nitrous oxide may be added to any one of these engine configurations. Nitrous oxide will produce different levels of added power depending on mechanical considerations. For instance: A nitrous oxide injection setup will add far more power to a vehicle equipped with a turbocharger, but lacking an intercooler/aftercooler, than a vehicle with an intercooler/aftercooler due to adiabatic efficiency considerations. Adding nitrous oxide can produce as little as a ten horsepower addition, or as much as three-hundred to five-hundred horsepower in some high-performance applications.

[edit] Other engine types

Ten cylinder, twelve cylinder and Rotary engines are not typically found in drag race settings, and are typically more difficult to modify. Ten and twelve cylinder engines can be found in certain German and British cars but are not common in drag racing. Rotary engines are, however, found in certain Mazda cars and can be heavily modified to produce immense power. In some cases upwards of 1000hp is possible to achieve. As such they have rapidly risen to prominence in some drag racing categories within the Sport Compact classes. Whilst it is impossible to reach the power levels of most types of V8 drag motors when using a rotary engine, the light weight of the rotary helps contribute to a power-to-weight ratio that enables them to compete with cars utilising V8 engines with greater hp. The world record E.T's are in the high sixes for rotary engines.

Some street registered vehicles are eventually capable of six second passes through the quarter-mile (400m). Most daily driven vehicles never get under the ten second time in the quarter-mile (400m). Times are usually taken to an accuracy of one one-thousandth of a second (1 ms) because of the possible closeness of the races.

[edit] Drag racing in the 21st century

Interest in drag racing has increased tremendously in the 21st century^{[citation needed]}. For many, drag racing and modification is just a hobby, but some have turned it into a business. Professional drag racing is a very expensive business in the top ranks. The sport has taken off so much in recent times areas with no drag racing facilities have converted urban roads into drag strips.^{citation needed!} This has been conducted in a safe and professional manner for both spectators and drivers.

Vehicles are separated into different classes according to engine capacity and whether the car is turbocharged/supercharged or naturally aspirated.

The races are often conducted in heats over a distance of 400m (1320ft, ¼mi) where the driver who crosses the finish line first wins and goes on to the next heat. This procedure is conducted until a final winner is achieved in the class. Cash prizes and trophies (as well as points, in pro classes) are awarded to the winners but most compete for the noteriety and the pure thrill of driving at such high speeds.

Many race drivers belong to car clubs that have strict criteria for anyone wanting to join.

People still however race illegally on long stretches of local roads as they say there is a greater thrill to do this than to race on a drag strip. This is street racing. Fans of, and participants in, organized drag racing deplore it.

[edit] Racing organization

The elapsed time from the light turning green to the car's front end passing through the "traps" at the other end ("far end") of the track determines the winner; this is the "E.T." or "time". In practice, it is necessary 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 crosses the electric eye ("the beam") in front of it before the green light comes on, the driver has "red-lighted" and is disqualified. (If both cars redlight, only the first car to cross is disqualified.) A driver who gets a substantial lead at the start is said to have gotten a "holeshot". The driver's reaction time and the car's top speed are also recorded, in addition to the e.t., on the "timeslip". The car that crosses the finish line first wins. A car can actually blow an engine part way down the strip and coast to the end of the track at a (relatively) lower top speed than the competitor, and still win with a lower elapsed time. This is called "heads-up racing", and is used in all professional ("pro") classes.

In the common Eliminator racing format, the losing car and driver are removed from the contest, while the winner goes on to race other winners, until only one is left. There are some instances where there are 3 cars remaining, and in this case one car, either chosen at random or the car with the fastest elapsed time thus far, gets a "bye run" where his or her car goes down the track by itself (in order to at least partially eliminate the advantage that would otherwise come from the engine having one less run on it), and then awaits the winner of the other two for the title. However, in most Eliminator formats, the bye runs take place only in the first round. Drivers are about equally divided between making a nice easy pass on the bye run so as not to stress the car unduly, making a real effort for the benefit of the spectators, or recording a time good enough to earn lane choice.

The National Hot Rod Association (NHRA) oversees the majority of drag racing events in North America. The next largest organization, the International Hot Rod Association (IHRA), is about one-third the size of NHRA. Nearly all drag strips is associated with one sanctioning body or the other. The NHRA is more popular with large, ¼ mile nationally-recognized tracks, while the IHRA is a favorite of smaller 1/8th mile local tracks. One reason for this (among others) is the IHRA is less restrictive in its rules and less expensive to be associated with.

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. There is even a class for aspiring youngsters - Junior Dragster.

In 1997, the FIA 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 (4 NHRA, 4 IHRA), which are:

• Top Fuel Dragster (TF/D) (NHRA and IHRA). The rail dragsters, or "diggers", the fastest class. There are also a Top Alcohol(TA/D) and Top Gas Dragster (TG/D).
• 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 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 or nitrous oxide. Cars running blowers are limited to 8.6 L (527 cubic inches) while cars with nitrous oxide can run up to 12.1 L (740 cubic inches).
• Pro Stock (NHRA and IHRA) Must maintain stock appearance. NHRA cars can run no more than 8.2 L (500 cubic inches) while IHRA cars can run a maximum of 13.1 L (820 cubic inches) ("Mountain Motors").
• Pro Stock Bike (NHRA only) Heavily modified motorcycles.

In addition to the above professional classes, these are some other popular classes:

• Top Alcohol Dragster
• Top Alcohol Funny Car
• Super Comp/Quick Rod
• Super Gas/Super Rod
• Super Street/Hot Rod
• Super Stock
• Stock
• Sport Compact (Smaller cars, with smaller engines)
• Top Sportsman (IHRA only, but at NHRA Divisional Races)
• Top Dragster (IHRA only)

A complete listing of all classes can be found on the respective NHRA and IHRA official websites (see external links).

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 8.801s for a quarter mile.

[edit] Drag racing performance facts

The fastest top fuelers can attain terminal speeds of over 530 km/h (330 mph) while covering the quarter mile (402 m) distance in roughly 4.45 seconds. It is often related that Top Fuel dragsters are the fastest accelerating vehicles on Earth; quicker even than the space shuttle launch vehicle or catapult-assisted jet fighter (however this ignores the hydrogen peroxide rocket dragsters such as Sammy Miller and Kitty O'Neil's 3.22 ET and 663 km/h (412 MPH) quarter mile world records set in 1977). In fact, a vehicle traveling at a steady 200 mph (322 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 531 km/h (0 to 330 mph) and then back to 0 in 20 seconds can be obtained. Deceleration of up to 5 G can be attained, enough to cause separated retinae in TF drivers, thanks to twin drag parachutes, a legacy from military aviation^[1].

The faster categories of drag racing are an impressive spectacle, with engines of over 5 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 210mph (340kph). 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 180mph (290kph) 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.

Drag racing has traditionally been the domain of big - usually American - cars with high capacity engines. However, the power to weight ratio of lighter, usually imported, cars has allowed them to be successful when their engines are modified and bodies lightened. The FIAT Topolino was the first to be exploited this way, in the notorious AA/FA, or Fuel Altered, followed by the more conventional modified VW Beetle. Recently there has been an increase in Sport Compact racing. Where smaller, especially Japanese and recently some European, cars, are raced, 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 10 second quarter miles. A database of several thousand ¼ mile timeslips can be viewed at www.dragtimes.com.

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 DaimlerChrysler 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.

One of the negative side-effects^{[citation needed]} of sport compact drag racing is the cheaper cars involved are often raced (illegally) on the street, where they cause trouble, with many drivers making a public nuisance of themselves. Illegal street racing was glamorised in the movie The Fast and the Furious. This phenomenon is just a resurgence of a problem which has existed ever since there have been cars and "hot rodders" (cf. American Graffiti, Rebel Without a Cause, etc.). However, cars are faster than they were 50 years ago and now many more innocent people are involved in street racing accidents. Closure of many dragstrips has also contributed to its resurgence; many drag racers and fans consider street racing a plague.

[edit] 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 turbos, superchargers, and nitrous oxide, specialized fuels (higher octane gas, methanol, etc...), improved suspensions, and a multitude of others.

[edit] The burnout

When approaching the starting line (also known as the staging area), most racers will apply water (formerly bleach) to the driven tires either by backing into a small puddle (the "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 burn-out. 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.

[edit] Staging

After the burn-out comes the "staging phase", 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 "pre-staged" 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 inches). Then the cars will nudge forward until the second (staged) light is lit. This indicates they are at the starting line. When both cars have lit both bulbs, the starter will engage the Christmas tree. If the racer moves too far the top 2 bulbs will go out and the driver is said to have "deep staged". While some drivers prefer this technique, some tracks and classes prohibit it.

[edit] The nitrous purge

The drivers push a button that activates a solenoid called a purge valve, which clears the gaseous nitrous oxide in the line out into the atmosphere without entering the motor. This brings the liquid nitrous oxide towards the motor, ensuring a correct mixture of nitrous oxide and fuel when the system is activated. Only cars with a nitrous oxide system installed can perform this action. Motors that utilize nitrous oxide are generally built with stronger internals to facilitate the increased combustion temperatures and pressures seen in a nitrous-Injected (sprayed) powerplant.

[edit] The race

Several things are important on the way down the track in drag racing. The first is not to cross into your 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 at the peak power point. 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, is 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.

If both cars break out, the car closer to their dial-in wins. In NHRA Junior Dragster racing, however, there is a maximum elapsed time where a car which is faster than the maximum permissible time is ejected from the entire race. This is faster than the official break out elapsed time.

[edit] Glossary

• Beam—starting line electric eye controlling "pre-staged" and "staged" lights
• Blow—supercharge; wreck. Said of an engine.
• Blower—supercharger (occasionally turbocharger); in '90s, generally grouped as "power adder" with turbocharger and nitrous
• Blown—supercharged; wrecked. Said of an engine.
• Blowover—flipping of a car, due to air under car lifting front wheels. Commonly suffered by diggers and floppers, not bodied cars.
• Breakout—running quicker than dial-in; also "breaking out". Grounds for disqualification if opponent does not commit a foul start or cross boundary lines.
• Christmas Tree (or tree) —the Chrondek timing lights
• Dial-in—when bracket racing, drivers must estimate or 'dial in' the time in which they expect to run. Therefore two unmatched cars in weight and power can compete, by a handicap system. If one runs a faster time then dialed in, it is a breakout.
• Digger—dragster (as distinct from a bodied car or flopper)
• Doorslammer—Pro Stock, Pro Mod, or other car with doors, from the requirement to have working doors.
• E-town—Oldbridge Township Raceway Park, Englishtown, New Jersey (raceway)
• Flopper—Funny Car, from the flip-up fiberglass bodies; does not apply to the early FCs.
• Fuel—mix of methanol and nitromethane ("pop", nitro); race class using it
• Fueler—any car running fuel or in Fuel class (most often, TFD)
• Holeshot—getting a significant advantage off the starting line. The other driver gets "holeshotted" or "left at the tree"
• Grenade—wreck an engine (the engine "grenaded") due to internal failure. Distinct from "popping a blower".
• Lit the tires—lost traction, causing smoke
• Nitro—nitromethane (sometimes incorrectly used to refer to nitrous oxide)
• Pedalling—working the throttle to avoid lighting the tires; "pedalled" it, had to "pedal" it
• Pop—nitromethane
• Pop a blower—suffer a backfire through the supercharger, causing a spectacular explosion. Usually results in loss of engine and race.
• Pro tree—timing lights which flash all three yellow lights simultaneously, and after four tenths of a second, turn green.
• Put on the trailer—lost (got "put on the trailer") or won (put the other driver on the trailer). From the obvious, losing drivers trailer their cars home.
• Rail—dragster (as distinct from bodied car or flopper). From the exposed frame rails of early cars.
• Redlight(ed) a.k.a. bulb(ed)—jump(ed) the start, left before tree turned green; automatic loss
• Silhouette—car closely resembling street model, but built specially for racing, such as Pro Stock car. Does not include Stock classes.
• Slicks—rear tires with no tread pattern and softer rubber compound, for increased traction
• Slingshot—early front-engined dragster, named for the driving position behind the rear wheels (erroneously attributed to launch speed)
• Standard tree—timing lights which flash in sequence five tenths of a second between each yellow light before turning green. Traditional form, before introduction of Pro tree.
• Top end—finish line of strip; high part of engine's rev band.
• Traction bars—rear struts fixed to rear axle to keep rear axle from twisting, causing wheel-hop and loss of traction; also called slapper bars.
• Trap(s)—timing lights at top end of race track to measure speed & E.T.
• Wheelie bars—rear struts fixed to rear axle, which protrude out to rear of car to help prevent car's front from rasing too high or flipping over on launch.

[edit] References

1. ^ The History of Fuel Dragsters

[edit] External links

• Dragtimes.com- an International Collection of Drag Slips and Drag videos viewable by car or by any 1/4 or 1/8th mile track. The only online Drag Slip Database.

[edit] Wikis

Automowiki