Sprint cars are historically identified simply as "big cars," distinguishing them from smaller midget cars. The earliest sprint cars had no wings at all — wingless competition was the only form of sprint car racing through the first decades of the sport. Winged sprint cars emerged as an innovation starting around 1958, when the first winged car competed at Columbus Motor Speedway in Ohio. By the early 1970s, wings with sideboards had become widespread in sprint car racing, creating the winged class that would go on to dominate the top tiers of the sport.
The wingless cars that persisted after wings became common represent the traditional configuration and are now sanctioned as a distinct class alongside the winged divisions.
Non-wing sprint cars use the same engine displacements as their winged counterparts — typically 410 cubic inch (6.7-liter) or 360 cubic inch (5.9-liter) naturally aspirated V8 engines running on methanol fuel with mechanical fuel injection. Some local and regional tracks impose rules specifying steel engine blocks or 305 cubic inch engines as cost-control measures. Some newer sanctioning bodies, specifically POWRi and Elite, permit fully open engines with no displacement limit.
Without wings, non-wing sprint cars generate significantly less downforce than winged cars. This reduces overall grip and makes the cars more difficult to drive through corners, creating handling characteristics that many in the sport consider more entertaining to observe and more demanding to master. The lack of the roll-over protection a wing provides also contributes to a higher frequency of dramatic accidents when cars go airborne. Chassis setup and tire choices differ from the winged configuration to compensate for the absence of aerodynamic load.
Cars do not use a conventional transmission, instead relying on an in-or-out gearbox and a quick-change rear differential. They have no electric starter and require a push-start before each race. Electrical systems are limited to a magneto for ignition.
The United States Automobile Club (USAC) is the primary sanctioning organization for wingless 410 cubic inch sprint car racing at the national level, running the USAC National Sprint Car Championship on a mix of asphalt and dirt tracks across the United States. Regional USAC wingless divisions — the USAC East Coast Sprint Cars, USAC Southwest Sprint Cars, and USAC West Coast Sprint Cars — extend 360 cubic inch non-wing competition to regional circuits.
The International Motor Contest Association (IMCA), founded in 1915 and the oldest active auto racing sanctioning body in the United States, sanctions the IMCA RaceSaver Sprint Car class, covering both 305 non-wing and winged sprint cars under a budget-oriented rules package designed to keep costs accessible for local competitors.
Historically, the USAC/California Racing Association (USAC/CRA), which formed after USAC absorbed the Sprint Car Racing Association (SCRA), has been a particularly strong presence for wingless sprint cars on the West Coast and in Indiana, as well as maintaining a presence on the East Coast.
Non-wing sprint cars occupy a unique cultural position in American short-track racing. Their proponents argue that the reduced grip from running without wings demands more from drivers, producing overtaking maneuvers and sliding exits from corners that differ markedly from the more planted handling of winged cars. The format has a strong and loyal following, particularly in the Midwest and on the West Coast, where weekly programs at local tracks keep the class active through the racing season.
Many sprint car drivers have crossed between the winged and non-wing formats throughout their careers, with the two disciplines each providing specific technique development. Because the same basic engine and chassis infrastructure underlies both classes, teams can sometimes run in both with modest configuration changes.