The GT Le Mans class in next year's United SportsCar Racing series will remain an open tire formula, despite confirmation that the other three classes will run Continental rubber.
The decision to allow competition between tire manufacturers in GTLM, which as GT is fought out between Chevrolet, BMW, Chrysler/SRT, Ferrari, and Porsche in the American Le Mans Series, reflects a desire to allow the cars to compete in the same specification in which they will go to the Le Mans 24 Hours in June.
ALMS rules boss Scott Elkins, who becomes vice president of competition and technical regulations with USCR sanctioning body IMSA for next season, said: "The GTLM class is based on the same ACO [Automobile Club l'Ouest] specifications as the GTE class internationally. This class is largely home to automotive manufacturer teams who desire flexibility in creating tire partnerships to develop technologies in racing that eventually find their way to the streets."
The factory GT entrants in the ALMS all use Michelins since BMW moved from Dunlops for this season, but they run on so-called "confidential" or development rubber rather than on a control tire. Two privateer teams, Alex Job Racing and Team Falken Tire, run on Yokohamas and Falkens, respectively.
The Prototype, Prototype Challenge and GT Daytona classes in the USCR series, which will kick off with the Daytona 24 Hours next January, will run on spec Continental tires produced by Hoosier.
The Daytona Prototypes that will race alongside LMP2 machinery and potentially DeltaWings in the P class and the GT cars in Grand-Am already run on Continentals, as do the ALMS LMPC ORECA-Chevrolet FLM09s that will form the PC class.
Grand-Am has an on-going contract with Continental, which began supplying the series in 2011.