Sprint car racing
Sprint cars are open-wheel race cars, designed primarily for the purpose of running on short oval, circular dirt or paved tracks. Historically known simply as "big cars," distinguishing them from "midget cars," sprint car racing is popular primarily in the United States and Canada, as well as in Australia, New Zealand, and South Africa.
File:DaveDarland2Kokomo.jpg|thumb|right|Dave Darland racing at Kokomo Speedway in 2007
Sprint cars have very high power-to-weight ratios, with weights of approximately and power outputs of over, which give them a power-to-weight ratio besting that of contemporary F1 cars. Typically, they are powered by a naturally aspirated, methanol-injected overhead valve American V8 engine with a displacement of 410 cubic inches and capable of engine speeds of 9000 rpm. Depending on the mechanical setup and the track layout, these cars can achieve speeds in excess of. A lower-budget and very popular class of sprint cars uses 360-cubic-inch engines that produce up to 775 horsepower. Sprint cars do not utilize a transmission but have an in-or-out gearbox and quick-change rear differentials for occasional gearing changes. As a result, they do not have electric starters and require a push to be started. The safety record of sprint car racing in recent years has been greatly improved by the use of roll cages, and, especially on dirt tracks, wings, which increase surface traction to protect the drivers.
File:2013 WoO Sprint Car Champion Daryn Pittman.jpg|thumb|right|Daryn Pittman's 2013 World of Outlaws winged sprint car
Many IndyCar Series and NASCAR drivers used sprint car racing as an intermediate stepping stone on their way to more high-profile divisions, including Indianapolis 500 winners A. J. Foyt, Mario Andretti, Johnny Rutherford, Parnelli Jones, Johnnie Parsons, Al Unser Sr., and Al Unser Jr., as well as NASCAR Cup Series champions Jeff Gordon, Tony Stewart and Kyle Larson.
The National Sprint Car Hall of Fame & Museum, located in Knoxville, Iowa, features exhibits highlighting the history of both winged and wingless sprint cars.
Engine
Wingless sprint cars
There are several sanctioning bodies for wingless sprint cars. The United States Automobile Club became the USAC/California Racing Association after taking over the Sprint Car Racing Association. The USAC/CRA remains popular on the West Coast, East Coast and in Indiana. However, historical lack of leadership in much of the US has resulted in a large number of groups and sanctioning bodies supporting wingless sprint cars.Wingless sprint cars are considered the traditional sprint cars, dating back to the first sprint cars in the 1930s and 1940s. Today, traditional and winged sprint cars are essentially the same vehicle, with many wingless cars having "stub outs" in the frame for attaching wings. They generally use the same and aluminum engines as their winged counterparts; many local tracks have rules mandating steel blocks and some displacements, in order to help control costs. Some newer regional groups, specifically POWRi and Elite have chosen to allow open engines with no limit to engine size. Their tuning and gearing are different for performance at lower RPMs than winged cars. Chassis set ups and tires are also different.
While they do not have the same top speed as a winged car because they lack downforce for improved traction, traditional cars are thought by many to be more entertaining to watch. Their relative lack of grip creates different driving characteristics than their winged counterparts, causing them to be more difficult to control through the corners. This, and the lack of roll-over protection a wing provides, makes them more prone to spectacular accidents.
Winged sprint cars
The world's first small-track winged race car was driven by Jim Cushman at the Columbus Motor Speedway in 1958. Cushman drove with his winged super-modified in several races and even won with it, starting a new trend of winged cars in sprint and super-modified racing. By 1959, up to half of the field was racing with a wing at Columbus Motor Speedway. In the early 1970s, many sprint car drivers began to put wings with sideboards on both the front and top of their cars. The added wings increase the downforce generated on the car, with the opposite direction of the sideboards helping to turn the car in the corners. The increased traction makes the car faster and easier to control.The wing also affects safety. The added downforce lessens the likelihood of going airborne. When cars do go airborne, the wings contact the ground first and break off or crumple upon hitting the ground, lessening the impact on the driver and the car. For these reasons, winged cars are safer to drive. Often teams are able to replace the wing during the ensuing stoppage and are able to continue once the race resumes.
In 1978, Ted Johnson formed the promotional body for winged sprint cars called the World of Outlaws. Racing throughout the United States from February to November, the World of Outlaws is the premier dirt sprint car racing series. Famous tracks featured in the series included the Eldora Speedway in Rossburg, Ohio, the Lernerville Speedway in Sarver, Pennsylvania, the Knoxville Raceway in Knoxville, Iowa and Williams Grove Speedway in Mechanicsburg, Pennsylvania. Each August, the Knoxville Raceway holds the Knoxville Nationals.
In 1987, Australia followed suit with its own national series for winged sprint cars called the World Series Sprintcars, founded by Adelaide based sedan driver and Speedway Park track promoter John Hughes. Famous Australian tracks used in the WSS have included Speedway Park/City in Adelaide, South Australia, Claremont Speedway and later Perth Motorplex in Perth, Western Australia, Valvoline Raceway in Sydney, New South Wales, Archerfield Speedway in Brisbane, Queensland, and the Premier Speedway in Warrnambool, Victoria. There is also a single meeting Australian Sprintcar Championship which has been run since 1963 and has been run under various class names before finally settling on the Australian Sprintcar Championship in 1979. While non-Australian drivers are free to race in the WSS and other meetings including the various state championships, only Australian drivers are permitted in the Australian Championship meeting.
The Grand Annual Sprintcar Classic at Warrnambool is the largest sprint car meeting in the world; in the 2014–15 season, the 2015 Classic race outdrew the Knoxville Nationals in entries.
Until the early 2000s, sprint cars in Australia were restricted to 6200 cc V8 engines as opposed to the 410 cui engines used in the United States and New Zealand. Brian Healey, the Sacramento-based Australian who owned Parramatta City Raceway, pushed for the change in 2003 to follow both nations to 410. Today, Australia follows the standard 410 ci formula, and has both the 410 and 360 cui formulae. Both formulae have separate Australian Championship meetings.
Midget cars
are smaller versions of a full size sprint car, normally non-wing only. Midgets date back to the 1930s as a very common form of sprint car racing, still very popular today and also sanctioned by USAC, POWRI, and others. They are powered by four-cylinder engines developing around 350 horsepower, but are only similar to their larger cousins in appearance.Mini sprint
s are similarly sized to midget cars, but have upright-style chassis and center-mounted, chain-driven four-cylinder motorcycle engines with displacements between 750 and 1200 cc.Micro sprints
Micro sprints are small racecars that are smaller versions of full sprint cars. A starter class for striving sprint car enthusiasts. 250/270cc single-cylinder two-cycle and 600 cc are the most popular micro sprint classes. They run side-mounted 600 cc motorcycle engines developing around 140 hp and are chain driven. They have chassis and bodies styled like those of full-sized sprint cars or midgets. Micro sprints are generally run on small dirt tracks that are usually a fifth of a mile or less in size, though they sometimes run on larger tracks. They can be either raced with or without wings; the latter are sometimes called "micro midgets" or "600 cc sprints". The general minimum weights for the cars to pass tech is 775 lbs for winged and 725 lbs for non-wing. Micro sprints are generally a cheaper alternative than racing mini sprints or midget sprints, but they can be as expensive as full-sized sprint cars.SpeedSTR
The SpeedSTR is a 1,250-pound open wheel car with a 72-inch wheelbase -- essentially a self-starting Midget. Originally powered by a 250 horsepower Dodge Neon engine, the division has transitioned to the K20 C1 Honda Turbo.Outlaw karts
Outlaw karts are go karts with roll cages and wings. They are some of the cheapest race cars that are very competitive, costing around $5,000. Most tracks are one sixth of a mile or less. Outlaw karts run side-mounted engines of various types. The beginner boxstock and boxstock divisions run pull start clone motors and are usually for the younger drivers first getting their start. The intermediate division run 250 cc dirt bike engines with the drivers or teams having the choice of running a four-stroke or a two-stroke. At some tracks, the intermediate division has to run a harder compound of tire. The biggest division in outlaw karts is the open division. The opens can run 450 cc four strokes, 500 cc two strokes, or 550 cc four-strokes. The 450 cc and 500 cc motors are the more popular options because the 550 cc motors are not run at all tracks, and the tracks that do run them make the kart weigh extra. The weight range for the karts is 150 lb to 500 lb.Sanctioning bodies
The NOS Energy Drink World of Outlaws is a division of 410ci winged sprint cars that run all over the United States and have a few events in Canada. The cars have wide right rear tires and 410 cubic inch engines with mechanical fuel injection. These sprint cars have no batteries or starters in them, necessitating push starts by a quad or truck. They also do not have flywheels, clutches or transmissions, but the direct drive systems can be engaged or disengaged from the cockpits. This is done both for weight reasons and tradition. Another tradition the WoO has pertaining their "A-main" is to have the cars line up four wide just before starting the race as a salute to fans in attendance, giving rise to the popular PA message "you want the best, now you have them four abreast".The All Star Circuit of Champions is an American motorsports sanctioning body of winged sprint car racing founded in 1970. The series sanctions 410ci sprint car races in Ohio, Indiana, Pennsylvania, Michigan, Illinois, Wisconsin, New York, and Florida. On average the series runs 40 races per year, starting February and ending in October each year.
The United States Automobile Club National Sprint Car Championship is a division of wingless 410 cubic inch sprint cars that run throughout the United States on asphalt and dirt tracks. The USAC also sanctions regional 360ci wingless sprint car series: the USAC East Coast Sprint Cars, USAC Southwest Sprint Cars, and USAC West Coast Sprint Cars.
The United Racing Company is a division for winged sprint cars that run mainly in the northeastern part of the United States in Pennsylvania, New Jersey, and Delaware. The URC started in 1948 with 11 races in its season. It slowly progressed to 28 races. The URC uses a 360 cubic inch engine which generates approximately. They race with alcohol fuel and use mechanical fuel injection to deliver it into the combustion chamber.
The American Sprint Car Series sanctions both winged and wingless sprint car racing within the United States. ASCS winged cars use a 360 cubic inch engine which lead to fans calling the cars "360s". The series was started by well-known racing promoter Emmett Hahn. The series national headquarters were located in Tulsa, Oklahoma for much of its history, but moved to Concord, North Carolina in 2024 following World Racing Group's purchase of the series. The all-time leader in wins for the series is Texan Gary Wright with 127 A main victories under his belt. Engine rules for the non-wing cars vary by series with some having unlimited displacement engines.
The International Motor Contest Association was organized in 1915, and is currently the oldest active auto racing sanctioning body in the United States. It sanctions traditional 305 non-winged and winged sprint cars under the IMCA RaceSaver Sprint Car class.
In Australia, sprint car racing is controlled by the Sprintcar Control Council of Australia who sanction the Australian Championships and the World Series Sprintcar series as well as the various state championships and other meetings held around the country.