Automotive Drag Racing

Automotive Drag Racing

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 especially Finland and Sweden. At any given time there are over 325 drag strips operating world-wide.

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.

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.

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]
* Some Dragracing modified 6cylinder cars have reached 1600hp when turbocharged and running 40-50psi.
* 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.

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) = 6,500hp+ (these are 500 cubic inch V8 Hemi Engines running on a mix of 85% Nitromethane to 15% methanol - 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.

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.