The Grand Touring Prototype (GTP) division will form the top class of the IMSA SportsCar series, which kicks off with the series' marquee event, the Daytona 24 Hours at the end of January. Cadillac and Porsche will also run these cars in the World Endurance Championship, as they chase the biggest sportscar race of all the Le Mans 24 Hours in its centenary year. So what does the future of US ... Keep reading
