The IMSA WeatherTech SportsCar Championship is a sports car racing series based in the United States and Canada organized by the International Motor Sports Association (IMSA).
The WeatherTech Championship, like the 24 Hours of Le Mans, features multiple classes of awe-inspiring sports cars racing on the track at the same time, making for seemingly endless passing throughout the race.
The WeatherTech Championship competes at North America’s premier sports car venues, including Daytona, Sebring, Watkins Glen, Road America and Road Atlanta. The majority of the races are timed races of 2 hours and 40 minutes, but the schedule includes iconic endurance races, such as the 12 Hours of Sebring, the 24 Hours of Daytona, and Petit Le Mans (10 hours).
The WeatherTech Championship has four classes of competition: Prototype (P), Prototype Challenge (PC), GT Le Mans (GTLM) and GT Daytona (GTD).
The Prototype (P) class features the fastest and most technologically advanced cars in North America. They are specifically designed and engineered for the race track and look drastically different than a typical street car. With the 2017 introduction of the Daytona Prototype (DPi), the class has seen new and renewed manufacturer involvement from Cadillac, Honda, and Mazda.
The Prototype Challenge (PC) class is a spec class featuring open-cockpit race cars and technology such as a carbon fiber chassis, carbon brakes and sequential gearbox.
The GT Le Mans (GTLM) cars are the most elite and fastest GT cars on the track. They are based on production models and are engineered to extract the maximum performance possible. The GTLM class is often heralded as one of the most competitive classes of racing, worldwide, and is where manufacturers such as BMW, Ferrari, Ford, GM (Corvette), and Porsche run their factory teams in North America.
The GT Daytona cars are enhanced (not defined by) technology. They are also based on production model cars but do not feature the same level of aerodynamics and power as the GTLM class cars.
Each car has two drivers (sometimes three or more for longer endurance races) who switch during the course of the race.
The GTLM class is the only class in the IMSA WeatherTech SportsCar Championship allowing open tire competition, with Michelin having been chosen as the technical partner from the leading automobile manufacturers in the world including BMW, Chevrolet (Corvette), Ferrari, Ford and Porsche. The GTLM class serves as a true proving ground for these leading manufacturers.