iRacing partners with the International Motor Sports Association in a mixed class series featuring both prototype and GT cars, headlined by the GTP and GT3 classes. The performance gap between the divisions challenges every competitor, no matter the car. Just as in iconic sports car events like the Rolex 24, the 12 Hours of Sebring and Petit Le Mans, drivers go head-to-head with their car/class rivals while keeping an eye out for the cars and drivers in the other two classes.