The Citroën SM, produced from 1970 to 1975, was a luxury sports coupe that pushed the boundaries of automotive engineering and design. It combined Citroën's long-standing commitment to innovation with
the performance prowess of Maserati, resulting in a vehicle that was both technologically sophisticated and visually striking. From its patented hydropneumatic suspension to its unique steering and lighting systems, the SM was a showcase of advanced features that set it apart from its contemporaries and cemented its status as a design icon.
The Hydropneumatic System: A Citroën Hallmark
At the heart of the SM's advanced engineering was an elaborate version of Citroën's patented hydropneumatic system, originally developed for the DS in the 1950s. This complex hydraulic network controlled not only the suspension but also the steering, clutch, and brakes. The system provided an exceptionally smooth and comfortable ride, allowing the car to maintain a consistent ride height regardless of load. This self-leveling capability was a significant advantage, contributing to both comfort and handling stability. The green suspension spheres, characteristic of Citroën's hydropneumatic cars, were a visible indicator of this sophisticated technology.The braking system was also integrated into this hydraulic network, featuring disc brakes on all four wheels, including the rear. The front disc brakes were mounted directly on the differential output shafts, an unusual design choice that helped minimize unsprung weight and allowed for a smaller scrub radius. The brake pedal itself was distinctive: small, round, and often referred to as a
