The IMSA Continental Tire SportsCar Challenge is a grand touring and touring car racing series run by the International Motor Sports Association. Originating from the Canadian Motorola Cup, the series was taken over by Grand-Am in 2001 to become the Grand-Am Cup following the demise of rival IMSA's Firehawk series of similar rules in the US. KONI became series sponsor for the start of the 2007 season when the series became known as the KONI Challenge Series, before renaming once more prior to the start of the 2009 season as the KONI Sports Car Challenge. The series name was once again changed for the 2010 season.
The Continental Challenge was the support series for Grand-Am's premier offering, the Rolex Sports Car Series. In 2014, the series became the support series for the United SportsCar Championship upon the merger of the Rolex Series and the American Le Mans Series. The series was renamed the IMSA Continental Tire Sports Car Challenge.
In traditional sports car racing format, the races are often run with both GS and ST classes on track simultaneously, which is known as a "combined" race. Occasionally the races will be run in "split classes", with separate races for both classes. This is especially common for shorter venues such as Lime Rock Park. Currently the races are 2 hours 30 minutes in length with a required driver change.
- All telecasts are exclusive to Fox Sports 1, formerly Speed Channel. All telecasts are uploaded to the series website after their initial airing.
The series uses two classes in each race:
- The Grand Sport (GS) class features large-displacement 6-cylinder, 8-cylinder, 10-cylinder or 12-cylinder sports cars as well as small displacement 4-cylinder forced induction sports cars.
- The Street Tuner (ST) class is for smaller 4-cylinder, 5-cylinder or 6-cylinder sedans, hatchbacks, coupes or convertibles.
All vehicles have fewer modifications than most series, using a "showroom stock" format.
The format is reminiscent of the original Trans-Am Series, combining conventional sports cars and touring cars, though the Trans-Am Series usually had a single driver per car, unlike the Continental Challenge, which has two drivers per car. Some vehicles in the Continental Challenge have actually been painted to resemble the original Trans Am cars, such as the Boss 302 Mustangs of George Follmer and Parnelli Jones or the original Sunoco Camaro. Several vehicles in ST have also competed in the SCCA's Pirelli World Challenge touring car class.
- The Bimmerworld 328i of Bill Heumann and Seth Thomas and the Compass360 Civic of Thilenius and Aschenbach finished the 2010 season tied in ST points. As both teams had the same number of wins and second-place finishes, Thilenius and Aschenbach won the title by virtue of having more third-place finishes.
- Matt Plumb was victorious in the final race and was the presumed champion, but upon official review he was determined to have been illegally entered in multiple cars, and thus received no points, handing the championship to Farano and Empringham.