Stock car racing is a form of automobile racing found mainly in the United States, Canada, New Zealand, Great Britain and Brazil. Traditionally, races are run on oval tracks measuring approximately a quarter mile to 2.66 miles (about 400 meters to 4.2 kilometers) in length, but are also raced on road courses[citation needed]. The National Association for Stock Car Auto Racing (NASCAR) is the world's largest governing body for stock car racing, and its Sprint Cup Series (named for its sponsor, Sprint Nextel Corporation) is the de facto premier series of stock car racing. Top level races are 200 to 600 miles (320-1000 km) in length. Average speeds in the top classes are usually within 70-80% of comparable levels of open wheel racing at the same tracks. Some stock cars may reach speeds of in excess of 200 mph (320 km/h) at tracks such as Indianapolis Motor Speedway and Lowe's Motor Speedway.
