Requirements For DPi and LM P2 Detailed In RegulationsThe 2017 IMSA WeatherTech SportsCar Championship will usher in a bold new era for professional sports car racing in North America led by all-new race cars in the series’ top Prototype (P) class.IMSA officials today released Technical Regulations for all four classes heading into the upcoming season, which opens on Jan. 28-29, 2017 with the 55th Rolex 24 At Daytona. The Prototype class will see a major technical shift in 2017, as two different types of race cars, Daytona Prototype international (DPi) and Le Mans Prototype 2 (LM P2), are introduced and will compete together for overall race victories. All Prototype cars, regardless of type, will use chassis built by one of four chassis constructors approved by IMSA, the Federation Internationale de l’Automobile (FIA) and the Automobile Club de l’Ouest (ACO): Dallara, Multimatic Riley, Onroak Automotive (Ligier) and ORECA.The technical differences between LM P2 and DPi are in the engines and bodywork. LM P2 cars will use constructor-specific bodywork and “spec” Gibson V8 engines. DPi cars are manufacturer-based, and require brand-specific bodywork and engines. DPi manufacturers for 2017 include Cadillac, Mazda and Nissan, with additional manufacturers showing strong interest in future participation.All LM P2 cars will compete in the WeatherTech Championship as homologated by the ACO/FIA. In contrast, DPi cars are homologated by IMSA. As part of the IMSA homologation process, DPi manufacturers/constructors may select an alternative specification for certain components such as brakes, shocks and wheels.Once declared and approved by IMSA, these alternative components – referenced in the IMSA Technical Regulations – become part of the overall homologation specification and required for use by each individual manufacturer-branded DPi car model. The DPi homologation process is scheduled to be completed prior to the Roar Before the Rolex 24 test on Jan. 6-8, 2017.The GT Le Mans (GTLM) and GT Daytona (GTD) classes utilize homologations and technical regulations established by the ACO and FIA, respectively.The Prototype Challenge (PC) class – which embarks on its final WeatherTech Championship season in 2017 – will continue to use the same IMSA Technical Regulations as in past seasons.