Group 4 Racing refers to a category of motorsport that was popular in the 1970s and 1980s, primarily in Europe. It was established by the Fédération Internationale de l'Automobile (FIA) to allow manufacturers to compete with modified production cars. Vehicles in this category were required to be based on road-going models, which made the races exciting and relatable to fans. The regulations for Group 4 Racing allowed for significant modifications, including changes to the engine, suspension, and bodywork. This led to the development of iconic cars like the Lancia Stratos and Ford Capri. The competition was fierce, and it played a crucial role in the evolution of modern rally and sports car racing.