The 924 was homologated in Group 4 and Porsche studied a version already prepared for track races and for rally, the Carrera GTR. The car was derived from the 924 Carrera GTP which had raced with the factory team at Le Mans in 1980. On the front of the car there were numerous air intakes for cooling the engine, turbo and brakes. The engine, type M31 / 70, was the well-known 4-cylinder 1984cc, which on this version produced 375 bhp.