At the time, the M1 platform was already gaining recognition as a legitimate challenger to Porsche in international competition. The Sauber-built cars drew attention for their advanced design and performance capabilities, reflecting a shift toward more specialized and purpose-built racing machines. The chassis featured a lightweight tubular steel spaceframe, significantly lighter than its Procar predecessor, paired with aerodynamic carbon fiber bodywork that reduced overall weight. Power came from a 3.5-liter inline six-cylinder engine producing more than 470 horsepower.
The car made its debut in the 1981 World Endurance Championship at the Nürburgring 1000 kilometers, where it showed early promise by running near the front before retiring due to mechanical issues. Its sister car secured victory in the same race. Weeks later, chassis 81.M1R.01 competed at the 24 Hours of Le Mans, demonstrating competitive pace but retiring late in the race after a series of mechanical failures.
Despite setbacks, the car continued racing through 1981 and achieved a notable victory in a Swiss Championship event in 1982. Ownership later passed through several hands, with documented competition activity into the late 1980s. In 1991, Peter Sauber reacquired the car and preserved it for over two decades.
Following a comprehensive restoration completed after 2014, the car returned to operational condition and has since undergone regular track use. As the only surviving purpose-built Group 5 BMW M1, it stands as a rare artifact of endurance racing history, supported by extensive documentation tracing its construction, competition career, and preservation. See it here.
