NHRA DRAG RACING 411
Drag Racing Jargon I Fun Facts I Cars of Drag Racing
Drag Racing Jargon
Breakout: Used only in handicap racing, "breakout" refers to a race car running quicker than the driver has predicted. The driver's prediction is called the dial-in and is posted on the race car. The driver who breaks out loses the race unless his or her opponent has committed a more serious foul, such as a red-light or crossing the centerline of the drag strip.
Burnout: Spinning the rear tires in water to heat and clean them before a run for better traction. In most classes, a burnout precedes every run down the dragstrip.
Christmas Tree: The noticeable electronic starting device between the lanes on the starting line. It displays a calibrated-light countdown for each driver.
Elapsed Time (e.t.): The time it takes a drag-race vehicle to travel from the starting line to the finish line.
Funny Car: With aerodynamically enhanced carbon-fiber bodies that loosely resemble the production cars on which they are based, these supercharged, fuel-injected, nitromethane-burning machines travel the quarter-mile in 4.6 seconds at more than 330 mph, slightly slower than a Top Fuel dragster. Most teams use an aluminum version of the 426 Chrysler Hemi engine that produces an estimated 7,000 horsepower.
Jr. Dragster: A half-scale version of a Top Fuel dragster designed to be driven by kids ages 8-17 in the NHRA Jr. Drag Racing League. Using a five-horsepower, single-cylinder engine, a Jr. Dragster can go as fast as 80 mph in as few as 7.90 seconds on the eighth-mile.
Methanol: Pure methyl alcohol used as fuel in Top Alcohol Dragsters, Top Alcohol Funny Cars, and even some Jr. Dragsters.
Nitromethane ("nitro") : Made specifically as a fuel for drag racing, it is the result of a chemical reaction between nitric acid and propane. Top Fuel dragsters and Funny Cars use nitromethane.
Nitrous Oxide ("nitrous," "N2O"): When injected into an engine under pressure, nitrous oxide gives the engine a sudden boost in power by introducing more oxygen into the fuel mixture. Nitrous oxide is not allowed in any NHRA category except Pro Mod (exhibition) and some E.T. bracket classes.
Pro Stock: Pro Stock cars look a lot like street cars, but looks can be deceiving. Extensive modifications to the cylinder heads, manifold, chassis, and suspension thrust them to 6.6-second elapsed times at more than 205 mph. The most popular engine choices for these carbureted, gas-burning vehicles are the GM big-block wedge, the Mopar Hemi, and the Ford wedge.
Pro Stock Motorcycles: Producing more than 300 horsepower, these highly modified motorcycles can cover the quarter-mile in less than 7.0 seconds at more than 195 mph. The chromoly steel chassis is cloaked in a lightweight, aerodynamically enhanced replica of the original motorcycle body, and the carbureted gasoline engine may be a Harley V-twin, a two-valve, or a four-valve.
Reaction Time: The time it takes a driver to react to the green starting light on the Christmas Tree, measured in thousandths of a second. A perfect reaction time is .000.
Red Light: When a race car leaves the starting line too soon — before the green light, or "go" signal — it activates the red light on the Christmas Tree and the driver has automatically lost the race.
Top Fuel Dragsters: The fastest-accelerating vehicles in the world, these are the most recognizable of all drag race cars. The 25-foot-long landlocked missiles can cover the quarter-mile in 4.4 seconds at speeds faster than 335 mph. The engine of choice is an aluminum version of the famous Chrysler Hemi. The supercharged, fuel-injected nitromethane-burning engines produce an estimated 7,000 horsepower.
Did you know …
… that the nitromethane-powered engines of NHRA Top Fuel dragsters and Funny Cars produce approximately 7,000 horsepower, about 37 times that of the average street car?
… that one cylinder of the eight cylinders of a Top Fuel dragster or a Funny Car produces 750 horsepower, equaling the entire horsepower output of a NASCAR engine?
… that the gasoline-powered engines of NHRA Pro Stock cars produce about 1,200 horsepower, about eight times that of the average street car?
… that an NHRA Top Fuel dragster accelerates from 0 to 100 mph in less than .8-second, almost 11 seconds quicker than it takes a production Porsche 911 Turbo to reach the same speed?
… that an NHRA Top Fuel dragster leaves the starting line with a force nearly five times that of gravity, the same force of the space shuttle when it leaves the launching pad at Cape Canaveral?
… that an NHRA Funny Car is slowed by a reverse force more than seven times that of gravity when both parachutes deploy simultaneously?
… that NHRA Top Fuel dragsters and Funny Cars consume between four and five gallons of fuel during a quarter-mile run, which is equivalent to between 16 and 20 gallons per mile?
… that NHRA Top Fuel dragsters and Funny Cars use between 10 and 12 gallons of fuel for a complete pass, including the burnout, backup to the starting line, and quarter-mile run?
… that NHRA Top Fuel dragsters and Funny Cars travel the length of more than four football fields in less than five seconds?
… that NHRA Top Fuel dragsters can exceed 280 mph in just 660 feet?
… that from a standing start, NHRA Top Fuel dragsters accelerate faster than a jumbo jet, a fighter jet, and a Formula One race car?
… that a fuel pump for an NHRA Top Fuel dragster and Funny Car delivers 65 gallons of fuel per minute, equivalent to eight bathroom showers running at the same time?
… that the fuel-line pressure for NHRA Top Fuel dragsters and Funny Cars is between 400 and 500 pounds, about 20 times greater than the pressure on passenger-car fuel pumps?
… that depending on size and angle, the large rear wing on an NHRA Top Fuel dragster develops between 4,000 and 8,000 pounds of downforce?
… that the 17-inch rear tires used on NHRA Top Fuel dragsters and Funny Cars wear out after four to six runs, or about two miles? Some brands of passenger-car tires are guaranteed for 80,000 miles.
… that it takes just 15/100ths of a second for all 7,000 horsepower of an NHRA Top Fuel dragster engine to reach the rear wheels?
… that it's desirable for an NHRA Top Fuel dragster to race with its front wheels inches off the ground for about the first 200 feet of the run? This ensures proper weight transfer to the rear wheels, a crucial part of a good launch and quick run.
… that the nitromethane used to power the engines of NHRA Top Fuel dragsters and Funny Cars costs about $16 per gallon?
Sources: NHRA Communications and Technical Departments, NHRA race teams, motorsports equipment manufacturers
Cars of NHRA
Where to see these classes: NHRA Full Throttle Drag Racing Series
Among the fastest-accelerating machines in the world, 7,000-horsepower Top Fuel dragsters are often referred to as the “kings of the sport,” and with good reason. They are capable of covering a quarter-mile in 4.4 seconds at more than 330 mph. Powered by a supercharged and fuel-injected 500-cubic-inch adaptation of the famed Chrysler Hemi engine, Top Fuel dragsters can burn up to 15 gallons of nitromethane fuel during a single quarter-mile run. Constructed of chromoly steel tubing and carbon-fiber composite, Top Fuel cars are 25 feet long and weigh 2,250 pounds in race-ready trim.
Similar to their Top Fuel counterparts but with a shorter wheelbase and a carbon-fiber body that loosely resembles a production-based automobile, Funny Cars routinely run in the 4.7-second range and are capable of speeds in excess of 330 mph. Funny Cars are powered by the same supercharged and fuel-injected 500-inch engines as Top Fuel dragsters. Funny Cars are also similar to Top Fuel dragsters in that they do not use a transmission but rather transmit power to the huge Goodyear rear slicks through a multistage clutch assembly that is activated by timers.
Often called “factory hot rods” because of their resemblance to production-based automobiles, Pro Stock cars are some of the most technologically advanced machines in drag racing. Built around a sophisticated tube chassis and four-link rear suspension, Pro Stock cars must conform to precise measurements and weigh no less than 2,350 pounds. Pro Stock engines use two carburetors and spec gasoline and are restricted to a maximum of 500 cubic inches. They can rev to more than 10,500 rpm and make in excess of 1,300 horsepower. A competitive Pro Stock car can run in the 6.6s at more than 208 mph.
Pro Stock Motorcycle
These highly modified vehicles, which can run under seven seconds at more than 195 mph, feature a purpose-built tube chassis and a lightweight, aerodynamically enhanced replica of original bodywork. The class features a wide variety of makes, models, and engines, including V-Twin entries from Harley-Davidson and Buell and inline four-cylinder-equipped Suzuki and Kawasaki models. To ensure a level playing field, pushrod-equipped V-Twin engines are limited to 160 cubic inches, and the high-winding four-cylinder engines cannot be larger than 101 cubic inches. Fuel injection is permitted, and spec gasoline is the only fuel allowed.
Top Alcohol Dragster
Top Alcohol Dragsters may look like Top Fuelers, but they have ¬significant differences. Whereas Top Fuelers use supercharged, nitro-burning engines, Top Alcohol Dragsters may use a supercharged methanol-burning engine or an injected nitromethane combination. The injected nitro cars do not use a transmission, and the supercharged cars have three forward speeds. Weights vary according to combination but are generally between 1,975 and 2,050 pounds. Like Top Fuelers, Top Alcohol Dragsters are restricted to a maximum wheelbase of 300 inches. A typical run is in the 5.2s at more than 270 mph.
Top Alcohol Funny Car
Similar in physical appearance to their nitro-burning Funny Car counterparts, Top Alcohol Funny Cars are restricted to the use of methanol fuel and have a three-speed transmission. Top Alcohol Funny Cars feature basically the same chromoly steel chassis as the nitro cars and are fitted with the same carbon-fiber replica bodies, though the Top Alcohol Funny Car bodies do not need as much downforce and use a much smaller rear spoiler. Top Alcohol Funny Cars are capable of performances in the 5.5s at more than 260 mph.
No category in NHRA competition features more variety than Comp. Dragsters, altereds, street roadsters, coupes, sedans, front-engine nostalgia dragsters, sport compact cars, and trucks race in 87 classes. The engine combinations are just as diverse as the vehicles, from turbocharged four- and six-cylinder engines to Pro Stock-style ¬V-8s and nitrous-oxide-equipped mountain motors. Most cars are classified using a formula that divides total car weight by cubic inches. Each class is assigned an index based on what a well-built car should run, and races are handicapped according to those indexes.
Super Stock vehicles may look like ordinary passenger vehicles, but they are highly modified race cars. The category features primarily late-model sedans and vintage muscle cars, and entries are classified using a system that divides factory shipping weight by NHRA-factored horsepower. Significant engine modifications are permitted, but the vehicle must retain the correct engine block, cylinder heads, and carburetor. The top class is SS/AH, which is exclusively for '68 Dodge Dart and Plymouth Barracuda factory race cars. Cars are handicapped using an index system, and the breakout rule is enforced.
Stock cars are similar to their big brothers in Super Stock, but the rules regarding everything from engine modifications to body alterations are much stricter. Virtually any car is eligible to compete, and entries are classified using a system that divides factory shipping weight by NHRA-factored horsepower. Bodies must be unaltered and retain a full factory interior. Tires are limited to a maximum nine-inch-wide rear slick. Engines must be correct for the make and model vehicle and must retain stock cylinder heads, intake manifold, and carburetor or fuel injector. Modifications are limited to a basic balancing and rebuild with only a few performance enhancements.
The quickest of the heads-up Super classes (8.90 index), Super Comp is composed primarily of dragsters. Engine, chassis, and body modifications are virtually unlimited, though all entries must adhere to NHRA safety standards. Four- and six-cylinder-powered entries may have a minimum weight of 1,000 pounds; all others cannot weigh less than 1,350 pounds. Most Super Comp cars are capable of running well under the 8.90 index but use a number of electronic aids, including a timer and adjustable throttle, to run close to the index without running quicker than it, or breaking out.
Super Gas entries, which run on a 9.90 index, are primarily full-bodied cars and street roadsters. No dragsters or altereds are permitted. Rules regarding engine and chassis modifications are extremely liberal, though the use of exotic fuels is prohibited. The minimum weight is 2,100 pounds except for four-cylinder-powered cars, which may have a minimum weight of 1,200 pounds. As in Super Comp, competitors use electronic timers and throttle stops to run as close to the class standard without going under. Also as in Super Comp, races are staged using a four-tenths Pro start.
At NHRA Lucas Oil Drag Racing Series races and select NHRA POWERade Drag Racing Series events, Super Street racers compete on a fixed 10.90-second index. All vehicles must be full-bodied cars and weigh no less than 2,800 pounds except for six-cylinder cars, which may have a minimum weight of 2,000 pounds, and four-cylinder- and rotary-powered cars (1,200 pounds). Engine and chassis modifications are virtually unlimited. Racers compete on a five-tenths Pro Tree.
Jr. Dragsters are half-scale versions of a Top Fuel dragster. Featuring a five horsepower engine, a Jr. Dragster can go as quick as 7.90 seconds and as fast as 85 mph on the eighth-mile. NHRA Jr. Drag Racing League competition is held at most of NHRA's 140 member tracks.
Where to see Jr. Dragsters: NHRA Jr. Drag Racing League member tracks
Just about any vehicle, from a dragster to a muscle car to a grocery-getter, can compete in E.T. bracket racing at NHRA's more than 140 member tracks in the United States, Canada, Mexico, and Puerto Rico. Believe it or not, even snowmobiles are welcome.
Where to see E.T. bracket racing: NHRA Summit Racing Series member tracks
Street Legal cars are vehicles that are legal to drive every day on the street with valid registration and insurance. These foreign and domestic vehicles range from late-model passenger cars and trucks to today's sport compacts. These cars typically run at NHRA Drags: Street Legal Style presented by AAA events, but they can also run at the NHRA Summit Racing Series events.
Where to see Street Legal Style racing: NHRA Drags: Street Legal Style presented by AAA member tracks