IMSA · History

Based in Daytona Beach, Florida, the International Motor Sports Association (IMSA) is the sanctioning body for endurance and sports car racing in the United States. Founded in 1969, it has run the championship that brings prototypes and GT cars to North America's leading circuits since 2014, under the name IMSA WeatherTech SportsCar Championship from 2016. With the merger announced in 2013, it became a wholly owned subsidiary of NASCAR.

Founding and early years

John Bishop, a former executive director of the SCCA, and his wife, Peggy, founded IMSA in 1969 with the backing of NASCAR founder Bill France Sr. The articles of incorporation were filed in Connecticut on June 23, 1969. France held 75 percent of the stock and Bishop the remaining 25 percent. The new body's first event was a Formula Vee and Formula Ford race at Pocono Raceway in October of that year, watched by 328 spectators.

The IMSA GT era

The IMSA GT Championship was launched in 1971, bringing the format of international endurance racing to North America. Camel cigarettes became the series sponsor in 1972, and the championship came to be known as Camel GT. The 12 Hours of Sebring joined the calendar in 1973. Two years later the All American Grand Touring (AAGT) series was created for American cars, and turbocharged engines were allowed from 1977. The Grand Touring Prototype (GTP) category followed in 1981, building on two Jean Rondeau-built Inaltera prototypes that had raced as invited entries in 1977.

Changes of ownership

In January 1989 the Bishops sold the company to Mike Cone and Jeff Parker, owners of the St. Petersburg Grand Prix, and Mark Raffauf succeeded John Bishop as president. In the early 1990s Cone and Parker sold the organization to Charles Slater, who passed it on to Roberto Muller and Andy Evans in 1996. Evans renamed it Professional Sports Car Racing (PSCR). In 2001 Don Panoz bought PSCR and restored the original name.

American Le Mans Series and Grand-Am

Panoz had already teamed up with the Automobile Club de l'Ouest (ACO), the organizer of the 24 Hours of Le Mans, to create Petit Le Mans at Road Atlanta in 1998. The American Le Mans Series (ALMS) followed in 1999 as a full season run under the ACO rulebook. Grand-Am Road Racing, backed by the France family, made its debut in 2000 with lower-cost machinery such as the Daytona Prototypes. The two series ran as rivals until 2012, when Panoz sold the ALMS to NASCAR-owned Grand-Am and helped broker a merger with the Rolex Sports Car Series.

The unified championship

Announced in 2013 as the Tudor United SportsCar Championship, the new series made its debut at the 24 Hours of Daytona on January 25-26, 2014, with four classes: Prototype, Prototype Challenge, GT Le Mans and GT Daytona. The first win went to the No. 5 Action Express Racing Corvette DP of Portugal's João Barbosa, Brazil's Christian Fittipaldi and France's Sébastien Bourdais, by 1.461 seconds. Ed Bennett took over as chief executive in January 2014, and WeatherTech replaced Tudor as title sponsor in 2016. DPi cars arrived in 2017, LMP2 became a separate class in 2019, GTD Pro replaced GTLM in 2022, and in 2023 the new GTP class, with hybrid prototypes built to the LMDh rules agreed with the ACO and the FIA, took over from DPi. In October 2019 John Doonan was named president, succeeding Scott Atherton.

Endurance racing and other series

The Michelin Endurance Cup, created in 2014 as the Tequila Patrón North American Endurance Cup and sponsored by Michelin since 2019, groups events such as the 24 Hours of Daytona, the 12 Hours of Sebring, the Six Hours of Watkins Glen and Petit Le Mans. IMSA also sanctions the Michelin Pilot Challenge, for TCR and GT4 cars, and since 2023 the VP Racing SportsCar Challenge, for LMP3 and GT4 machinery. Among Latin American drivers, Brazil's Felipe Nasr won the top-class title in 2018, 2021 and 2024, and won the 24 Hours of Daytona with Porsche Penske in 2024, 2025 and 2026.