The imperious Citroën SM is celebrating its fiftieth anniversary in March 2020 and the magnetic automotive creation remains as seductive and desirable than ever before.
The avant-garde thinking behind this magnificent creation was a major example of collaboration between iconic French and Italian manufacturers.
The DS was already a legend when Project ‘S’ was launched in the 1960s. The aim was to take advantage of the DS’s technological lead and image to produce a sports vehicle that would be in the same vein. Jacques Né, the engineer in charge of the project, initially had the 24 Hours of Le Mans in his sights, but Managing Director Pierre Bercot quickly redirected his research towards a prestige car, one to be placed above the DS, which was still in production at the time.
Sharing components was essential during development. The new creation was to be based on the chassis of a DS and assembled on the same assembly lines at the Quai de Javel, in Paris.
Under the direction of Robert Opron, a team led by Jean Giret and Jacques Charreton finalised the design of what would become the SM. A 1:1 scale model was produced in the Rue du Théâtre workshops. The arrival of Maserati in Citroën’s fold opened up new prospects and an Italian workshop launched a study into a small, modern V6…
Unveiled at the 1970 Geneva Motor Show, the SM emerged as the worthy heir to the powerful DS. The Grand Tourisme had many strengths: a line that was as fluid as it was aggressive, a chassis based on the famous hydraulic suspension, a futuristic interior with egg-shaped dials and a Maserati V6 engine. The DS’s DNA was amplified.
Under the long bonnet, the 90° V6 acquired two overhead camshafts per cylinder bank. The cylinder capacity was deliberately limited to 2,670cc to remain under the very penalising barrier in France of 16 fiscal horsepower. Particularly compact (31 cm in length) and very light (140 kgs), the alloy block is initially fed by three dual-body Weber carburettors for 170 hp at 5,500rpm before receiving electronic fuel injection developed with Bosch to increase the power to 178hp while gaining flexibility of use.
The SM took over the central hydraulic system that made the DS a success. Green LHM fluid fed and supported some of the main functions: suspension, braking (controlled by a mushroom-shaped pedal), steering and vertical adjustment of the headlights. Special attention was paid to studying the suspension to give the SM the fastest traction in the world with a notable difference compared to the DS – a tie-rod front axle.
Citroën SM – Continued Innovation
Steering was just one of the SM’s great innovations. Called DIRAVI, for DIrection à RAppel asserVI (memory power-assisted steering), it had the special feature that it hardens with speed, thanks to a hydraulic governor mounted at the end of the gearbox. This steering was particularly light and direct in town and more stable at high speeds.
A new dimension was added to automatic headlight correction. Like the DS, the SM benefited from two rotating external long-range headlights. The six halogen headlights, designed by Cibié behind their Saint-Gobain shop front, also acquired plates that automatically adjusted height according to the car’s attitude.
The stamping and fitting of the bodies were performed in the Chausson de Gennevilliers factory. Everything was then transported by lorry to the Quai de Javel for final assembly on the same assembly lines as the DS.
Fifty years on, and the Citroën SM is a symbol. Comfort and road handling make it a very modern car. Its lines, both inside and out, remain at the forefront with its mushroom pedal, the whispering hydraulic system and variable assisted steering. And although popular thinking credits the end of its marketing to the sudden increase in petrol prices with the oil crisis, the SM remains one of the most efficient GTs of the era. DS Automobiles was born out of the same desire to bring avant-gardism, refinement and advanced technologies to its contemporary creations.
Georges Pompidou, President of the French Republic at the time of its launch, but also Leonid Brezhnev, the Shah of Iran, Haïlé Sélassié, Burt Reynolds, John Williams, Johan Cruyff, Bernard Pivot, Line Renaud or Jay Leno had or still have a Citroën SM. And Daniel Craig admits that it has always been the car of his dreams…
An annual meet-up for car enthusiasts, Rétromobile, will once again this year spread over 72,000 m² at Paris Expo, Porte de Versailles. The Show will be open to the public from Wednesday 5 February to Sunday 9 February from 10 am to 7 pm (Wednesday and Friday evenings until 10 pm).
Did you know?
- Jacques Né’s first ‘S’ project was to devise a vehicle that could be entered in the 24-Hour Le Mans race.
- The first new model from the Robert Opron era after the death of Flaminio Bertoni, the SM was also the last creation designed at the Rue du Théâtre in Paris, before the style department moved to Vélizy.
- At the time of marketing in June 1970, the price for the SM was 46,000 FF (French Francs equivalent to €46,400 today). The SM Injection was sold for 84,000 FF in April 1975 (equivalent to €54,000 today).
- The colour Brun scarabée (Beetle Brown) was the best-selling shade. Feuille dorée (Gold Leaf) and Sable métallisé (Metallic Sand) also marked the beginning of the SM’s career.
- 12,920 cars were produced at the Quai de Javel plant in Paris between 1970 and 1975.
- Henri Chapron Bodywork built seven Mylords (convertible), two Elysées (convertible for official ceremonies) and seven Operas (four-door). Heuliez designed two SM Espaces.