The IMSA GT Championship was a prominent sports car racing series that captivated audiences from 1971 to 1998. Organized by the International Motor Sports Association, the series primarily held races in the United States, with occasional events in Canada. Over nearly three decades, the championship underwent significant changes, adapting to new technologies and shifting racing landscapes.
The Early Years
The IMSA GT Championship was founded in 1969 by John and Peggy
Bishop, along with Bill France, Sr. Racing officially began in 1971, targeting two of the FIA's stock car categories. The inaugural race at Virginia International Raceway was a surprising success, drawing both drivers and spectators. In the following years, the series expanded, with John Bishop securing sponsorship from R. J. Reynolds and introducing new racing categories.
By 1975, the All American Grand Touring (AAGT) category was introduced, marking a significant shift in the series. The mid-1970s saw the inclusion of turbocharged cars and the introduction of the GTX category, based on Group 5 rules. These changes reflected the series' adaptability and willingness to embrace new technologies and racing formats.
The Rise of GTP
In 1981, the IMSA GT Championship introduced the GTP class for sports prototypes, diverging from the FIA's Group C rules. This era saw the rise of purpose-built GTP cars, which became a defining feature of the series. The GTP class was known for its lack of emphasis on fuel consumption, allowing for more aggressive racing strategies.
Throughout the 1980s, the series was dominated by manufacturers like Porsche, Nissan, and Toyota. The Porsche 962, introduced in 1984, became a dominant force, followed by Nissan's control of the series in 1988. The GTP era was marked by innovation, with advancements in antilock brakes, traction control, and active suspension.
Decline and Transition
Despite its success, the GTP category faced challenges in the early 1990s. Rising costs and the departure of key manufacturers led to a decline in participation. In 1993, the series introduced the World Sports Car (WSC) category, replacing the GTP and Camel Lights classes. The WSC cars featured open-top designs and production engines, marking a new direction for the championship.
The series continued to evolve, with changes in sponsorship and ownership. In 1999, the IMSA GT Championship was rebranded as the American Le Mans Series, aligning with international racing standards. Despite its eventual conclusion, the legacy of the IMSA GT Championship lives on, influencing modern sports car racing and continuing to inspire enthusiasts worldwide.
