LMDh (Le Mans Daytona h)[1] is a sports prototype category that competes alongside Le Mans Hypercar entries in the Grand Touring Prototype (GTP) class of the IMSA SportsCar Championship from 2023.[2] It also competes in the Hypercar class in the FIA World Endurance Championship.[3]
The LMDh ruleset was created jointly by the International Motor Sports Association (IMSA) and the Automobile Club de l'Ouest (ACO).[4] The cars serve as the successor to the Daytona Prototype International class, utilising regulations that were planned to become the next-generation Daytona Prototype International ruleset, converged with the Le Mans Hypercar ruleset.[5]
The FIA World Motor Sport Council had allowed LMDh cars to participate in the 2022 WEC season on a race-by-race basis, "to ensure the seamless introduction" in 2023; however, no LMDh cars would end up participating at any of the 2022 season races, and they would instead make their debut in the 2023 season.[6]