Fuel injection in NASCAR

Fuel injection in NASCAR reflects the technology used by production Toyota, Chevrolet, and Ford vehicles on the road today. Currently, no production automobile manufacturers use carburetors as a part of the fuel delivery system.

Fuel injection technology has been found to be one of the most important technical advances in stock automobiles since NASCAR was founded in 1947. Some find it more significant than the transition from rear-wheel drive vehicles to front-wheel drive vehicles during the late 1980s; which ultimately failed and caused NASCAR to revert to using a cast-iron eight-cylinder rear-wheel drive engines. People who like contemporary NASCAR racing are avid fans of technology; they are curious about how fuel injection affects the outcome of a typical NASCAR race. However, they must also placate the "traditional" NASCAR fan who has been watching NASCAR before the 1980s. While the sale of manual transmission vehicles would start to decline in the 1970s and plummet in the 1980s, NASCAR continued to hold a strict policy of only allowing manual transmission vehicles in the Sprint Cup Series to this very day.

Cars that compete in the NASCAR Xfinity Series (previously known as Nationwide Series) cars are powered by carburetors; in addition to trucks that compete in NASCAR's Camping World Truck Series.

During the 1957 NASCAR Grand National season, president of NASCAR, Bill France, Sr., immediately banned fuel injection from NASCAR. This ruling was in result to the dominance of the 1957 Chevrolet. General Motors did not offer many 1957 Chevrolet stock productions with mechanical fuel injection. However, enough were produced to allow it into NASCAR competition due to homologation rules. This ban on fuel injection would continue into the 21st century.

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