Typically Citroën, the sporty CitroënSM went its own way in styling and features. Unique oleopneumatic suspension could vary ride height over a towering range.
Citroën, the veteran French automaker, was into "high tech" long before we'd ever heard the term. It pioneered front-wheel drive with its famous Traction Avant sedans of 1934. Next came the futuristic DS19 of 1955, with a high-pressure hydraulic system for powering the brakes as well as a unique oleopneumatic suspension system with integral self-levelling. By the Sixties, Citroën had a reputation for cars engineered like no other, which would later include the Citroën SM.
Though Citroën had been toying with the idea of a fast sporty coupe, its four-cylinder engines just weren't up to the job. But in 1968, Citroën took over Maserati, the famed Italian sports-car builder, and suddenly the idea seemed plausible.
Soon after this merger was formalized, Citroën learned how resourceful, speedy, and efficient Maserati's designers could be. Accordingly, it asked the Italians to develop a new high-performance engine of about 2.7 liters (French car taxes took a vertical leap above 2.8-liters displacement) that might power a sportier Citroën and a new Maserati.
The result was a 90-degree V-6 with twin overhead camshafts per cylinder bank, actually a close relative of Maserati's existing right-angle quad-cam V-8. With 170 bhp in standard form, it was deemed suitable not only for the new Citroën but a downmarket version of Maserati's mid-engine Bora. The latter, called Merak, was tuned initially for 190 horsepower, later 220 bhp.
Citroën, meantime, set about designing its own new GT, which emerged as the Citroën SM (for "Sport Maserati"). Riding a 116.1-inch wheelbase and measuring a grand 192.8 inches long overall, it was a heavy (3200-pound), extravagantly equipped 2 + 2 styled along the lines of the DS sedans, with a low, shapely nose and abbreviated overhangs front and rear. Setting it apart was a sloped roofline ending in a high tail, with a lift-up hatch incorporating a large, curved backlight.
Unusual even for Citroën, the Citroën SM had no fewer than six headlights (basically a conventional quad-lamp system plus auxiliary driving lights), with the inboard units linked to the steering so that they'd turn with the front wheels -- shades of the Tucker! European models mounted this luminary sextet behind a full-width transparent cover, with a center section for the license plate. Both cover and driving lamps were omitted for the American market as not meeting federal regulations.
The Citroën SM's V-6 sat longitudinally behind the front-wheel centerline to drive through a beefy 5-speed gearbox (also used in the Merak as well as the later mid-engine Lotus Esprit and Peugeot's mid-Eighties 205 Turbo 16 Group B rally car). As on the big Citroëns, brakes (here, four-wheel discs) and all-independent suspension continued to be powered hydraulically from engine-driven pumps, but now the steering was too. Lightning quick @ mere 2.0 turns lock-to-lock), it would self-center at rest without any driver assistance -- a bit unnerving to the uninitiated.
As always, Citroën's oleopneumatic suspension breathed a literal sigh of relief after engine shutoff, eventually letting the car settle on its bump stops as internal pressure eased. Conversely, the system could be "pumped up" so as to raise the car to maximum wheel travel in rebound, which made for a very stiff ride but facilitated tire changes (and fording streams). Inside was a typically Citroën dash, with oval instrument dials, unconventional minor controls, and the ever-present floor-mounted brake "button" that had virtually no movement no matter how hard you pressed (the hydraulics did all the work).
Alas, the Citroën SM was knocked for a loop by the 1973-74 energy crisis, which rendered fast tourers like this almost unsaleable for a time and led to big financial trouble for the Citroën/Maserati "marriage," prompting Citroën to withdraw from the U.S. market after 1974. Citroën SM production limped along for about another year, then ceased following Citroën's acquisition by Peugeot. Later Citroën SMs were fitted with fuel injection, raising V-6 output to 178 bhp. There was also a 3.0-liter version (mainly for export) with 180 bhp, offered only with Borg-Warner 3-speed automatic.
Road & Track magazine named the Citroën SM "one of the ten best cars in the world" in 1971, perhaps a dubious accolade in light of subsequent events, though it was easily justified at the time. Even in initial carbureted form, the big fastback Cit could reach 130 mph, and its "magic carpet" ride all but obliterated surface irregularities at such speeds.
For the Citroën SM, Maserati designed SM V-6 and used it to power its own mid-engine Merak two-seater.
Like the DS sedans, of course, the Citroën SM demanded a totally different driving technique. Its steering, for example, is not only super-quick but super-light, so it's easy to turn too sharply into a corner. It's just as easy to stand the car on its nose by being overly enthusiastic with the pressure-sensitive brake button.
But if you could adjust to its idiosyncracies, the Citroën SM was an ideal choice for long, fast journeys across Europe -- which was, after all, what it was designed for. High-speed performance is relaxed, aided by unusually good aerodynamics (long a Citroën passion) and that smooth, supple ride.
Though not a commercial success, the Citroën SM was an interesting departure for Citroën and somewhat influential. Its styling helped shape the DS-series' CX successor, while its engineering continued in the Merak (which also used the complete Citroën SM dash) and Maserati Khamsin even after Citroën and Maserati divorced. Citroën hasn't attempted anything like this since (and may not ever), leaving the weird and wonderful Citroën SM a singular sports coupe of endless "high-tech" fascination.
To learn more about Citroën and other sports cars, see:
To learn more about Citroën and other sports cars, see:
- How Sports Cars Work
- Sports Cars of the 1970s
- New Sports Car Reviews
- Used Sports Car Reviews
- Muscle Cars
- How Ferrari Works
- How the Ford Mustang Works