The Plymouth Superbird is a highly modified, short-lived version of the Plymouth Road Runner with applied graphic images as well as a distinctive horn sound both referencing the popular Looney Tunes cartoon character the Road Runner. It was the factory's follow-up stock car racing design, for the 1970 season, to the Dodge Charger Daytona of 1969, and incorporated many engineering changes and modifications garnered from the Daytona's season in competition.

Stock car racing is a form of automobile racing run on oval tracks and road courses measuring approximately 0.25 to 2.66 miles. It originally used production-model cars, hence the name "stock car", but is now run using cars specifically built for racing. It originated in the southern United States; its largest governing body is NASCAR. Its NASCAR Cup Series is the premier top-level series of professional stock car racing. Australia, Canada, New Zealand, Mexico, Brazil, Argentina, and the United Kingdom also have forms of stock car racing. Top-level races typically range between 200 and 600 miles in length.