Stock car racing is a form of
automobile racing found mainly in the
United States,
Canada,
New Zealand,
Great Britain,
Brazil and
Argentina. Traditionally, races are run on
oval tracks measuring approximately 0.25 to 2.66 miles in length.
NASCAR is the world's largest governing body for stock car racing, and its
Sprint Cup Series is the
de facto premier series of stock car racing. Top level races are 200 to 600 miles in length. Average speeds in the top classes are usually 70–80% of comparable levels of
open wheel racing at the same tracks. Some stock cars may reach speeds in excess of 200 mph at tracks such as
Daytona International Speedway and
Talladega Superspeedway. These tracks have come to be known as "restrictor plate tracks", a name that is derived from the "restrictor plate," device that was designed to limit top speeds to approximately 192 mph on such tracks.