1974 Citroen SM

Citroen acquired Maserati in 1968, giving them access to a high-performance engine for its 'Project S,' in many ways the last of the DS concept. Unveiled at the 1970 Geneva Salon, the new Citroen was considered the ultimate 'gentleman's GT.' With the powerful and smooth Maserati Quad OHC V6 engine, it was the fastest front-wheel drive in the world for the following ten years. The elegant and sculpted shape was penned by Robert Opron and boasted an incredible aerodynamic efficiency (initially published as having a drag coefficient of 0.26 but later revised to 0.339) that surpassed most road-going vehicles of the era. Its teardrop styling included a Kamm tail and fender skirts at the rear, ventilation intakes on the hood, and a wide front track tapering to a narrow rear track.

The Citroen SM went on sale in France in September of its introductory year in left-hand drive only, although right-hand drive conversions were later offered in the UK and Australia. It was Citroen's flagship vehicle that would demonstrate just how much power and performance could be accommodated in a front-wheel drive design. During its production lifespan, lasting from 1970 to 1975, a total of 12,920 examples were built with approximately 2,400 sent to the United States. In 1972, it won Motor Trend's Car of the Year award in the United States.

Project S began as a sports variant of the Citroen DS, a front-wheel drive executive car manufactured from 1955 to 1975. Named the 'SM,' this may have been the combination of the 'Project S' designation for 'S' and the 'M' for 'Maserati.' Thus, it is assumed that 'SM' represents 'Serie Maserati,' 'Systeme Maserati' or 'Sports Maserati.'

Mechanical Specification

Engine

The Maserati high-performance, four-cam, 90-degree V6 engine displaced 2,670cc and delivered 170 horsepower at 6,250 RPM with three Weber carburetors. By 1973, output had risen to 180 horsepower when displacement increased to 2,965cc. The lightweight, all-aluminum engine, positioned behind the front axle, was designed by Giulio Alfieri and had an unusual 90-degree angle between cylinder banks, giving it the flexibility of being assembled on existing V8 tooling. Bosch D-Jetronic electronic fuel injection, first offered in 1972, delivered 168 hp. A singular example was fitted with a Maserati V8 engine with 260 hp and another example had a turbocharged version of the V6 engine for setting land speed records at the Bonneville Salt Flats.

Transmission

Most of the Citroen SM vehicles receive a five-speed manual transmission, with a few fitted with a three-speed Borg-Warner automatic transmission that was optional in North America in 1972 and 1973, and in Europe from 1974 to 1975.

Chassis

The Citroen SM rested on a 114.2-inch wheelbase platform with an overall length of 192.6 inches, a width of 72.3 inches, and stood 52.1 inches tall. Like the DS, it had a hydro-pneumatic suspension with front parallel control arms, rear trailing arms, and front and rear anti-roll bars. Disc brakes with hydraulic assist at all four corners provided the stopping power. The front brakes were inboard and cooled via large ducts on the front underside of the car. The hydraulic system adjusted pressure front to rear according to the weight in the rear of the car.

There were self-leveling lights that swiveled with the steering, but since this technology was not legal in the United States, U.S.-destined cars were devoid of this technology.

A variable assist power steering combated torque steer common to high-performance, front-wheel drive vehicles, and adjusted hydraulic pressure on the steering centering cam according to vehicle speed, allowing a consistent steering feel at any speed. The steering was responsive, could turn easily at low speeds, and had two turns lock-to-lock. If the driver let go of the steering wheel, the steering would return back to center, to a straight-ahead position. Additionally, the height and reach of the steering column could be adjusted.

When the wipers were on the 'low speed' setting, the system monitored the current needed to drive the wiper motor. When it rained, the current's need was higher, and the system would adjust accordingly.

The standard wheels were steel with stainless trims. A factory-fitted option was the Michelin-developed lightweight caron-reinforced resin wheels intended for off-road racing, and weighed less than half the standard weight.

The hood (bonnet) was comprised of aircraft-grade aluminum, and the brightwork was made from stainless steel. Chrome was used for the 'plastichrome' 'SM' trim at the rear base of the rain gutter.

Interior

The Citroen SM had a small oval steering wheel, oval gauges, and adjustable bucket seats with center padding composed of many individual 'rolls.' When equipped with a manual transmission, the shift lever 'boot' had a highly stylized chrome gate.

Performance

The factory-quoted top speed of the Citroen SM in 1970 was 137 mph (220 km/h), with independent testing later revealing speeds of as much as 146 mph (235 km/h). The special V6 Citroen SM with a turbocharger developed by Jerry Hathaway (SM World) achieved a top speed of 202 mph (325 km/h) at the Bonneville Salt Flats in 1987, setting a land speed record for production vehicles in its class.

Production

Most of the Citroen SM vehicles were built in 1971 and 1972, with 4,988 in the former and 4,036 in the latter. The final two years saw the lowest levels of production, with 294 examples built in 1974 and 115 in 1975. 868 examples were built in 1970 and 2,619 examples in 1973. 1,250 examples were sent to the North American market in 1972 and 1,150 in 1973.

by Dan Vaughan

Since its founding in 1919, Citroen has consistently produced some of the most innovative cars in the world. From the diminutive Deux Chevaux to the smooth and regal DS, the French carmaker's history is filled with avant-garde designs and adventurous engineering forays. Some of Citroen's innovations caught on, such as the manufacturer's early adoption of front-wheel-drive and aerodynamic body styling. Other hallmark features of the carmaker's products, though, remained idiosyncratic novelties. Apparently, nobody else understood the benefit of a central hydropneumatic system that controlled the power steering, power brakes, and height-adjustable suspension all at the same time…

But while many of Citroen's signature engineering touches were too complicated and risky for other carmakers to adopt, they endowed Citroen's products with a mechanical finesse and individuality rarely seen on high-volume automobiles. Citroen developed elegant solutions to problems that most manufacturers simply ignored. Knowing that people drove their cars on all sorts of roads, Citroen created an ultra-smooth suspension that was height-adjustable so drivers could cope with various road surface qualities. The real-world advantages of front-wheel-drive and aerodynamic bodies were being discovered by more and more carmakers and buyers.

In the decades following World War II, Citroen's 2CV and DS proved that innovation could sell. Both of those models realized huge production figures, and both were produced for many years. But when 1970 rolled around, the French brand decided to try something riskier: a sporty Citroen.

The DS and 2CV were both excellent cars exhibiting great attention to detail. Their roles, though, were staid. The DS was a family car. The 2CV was an economy car. So when Citroen decided to challenge the automotive establishment with a sporty car of its own, they had little experience in producing vehicles whose real ambitions were to become heroes of the racetrack or playthings of the rich and famous. The sporty Citroen, the SM, accordingly sold slowly and puzzled potential customers. Why should any car with sporting intentions need a height-adjustable suspension? Why such an unconventional shape? And why front-wheel-drive?

Had the SM been a true sports car, these features may have been a death sentence. In reality, though, the SM was a grand tourer—and Citroen knew that its idiosyncratic design traits had just as much business belonging to a GT car as to a family sedan. The advanced suspension ensured a good ride quality on all road surfaces. The aerodynamics lowered noise levels at high speed and provided better fuel economy, both important characteristics in a vehicle intended to swallow distance in suave comfort. And the front-wheel-drive endowed the SM with great usability, with surefooted road manners and impressive foul-weather capabilities.

Driving enthusiasts often derided front-engined, front-wheel-drive cars for their unwieldy forward weight bias, a feature that tends to result in heavy understeer and sloppy handling. The SM, though, was technically a mid-engined car: its engine fit entirely behind the front axle line. Coupled with an advanced steering system, this front-mid-engined layout enabled the SM to avoid some of the inherently placid handling characteristics of a front-wheel-driver. The Citroen's handling may have even been too lively for some drivers, with its quick steering a copious body roll likely surprising more than a few first-time pilots.

The front-mid placement of the SM's engine accounted for much of the car's character, but the engine itself accounted for far more. The all-aluminum V6 was an advanced motor. With very oversquare bore/stroke dimensions, revs came easily. Dual overhead cams per cylinder bank and three Weber carburetors served as visual indicators of the engine's exotic nature. But, for the uninformed, the real surprise came from the name scrawled on the valve covers: Maserati.

Prior to the SM, Citroen had created marvelous cars with advanced engineering and lovely styling—but the company's engines remained conventional and boring. The SM, then, represented the first (and arguably only) Citroen to have it all: complicated and exquisite engineering, aerodynamic and enticing styling, and finally an engine that deserved to tote the whole package around.

The Maserati motor beneath the SM's hood was no coincidence. Citroen purchased Maserati from the Orsi family in 1968, in a bizarre merger that resulted in some predictably bizarre vehicles. Two of those Franco-Italian oddballs, the Citroen SM and Maserati Merak, were wholly developed under Citroen's ownership of Maserati and intended from the start to share a new, Maserati-developed V6. Surprisingly, this engine ended up in the SM two years before the Merak, as that Maserati did not reach production until 1972.

Citroen knew that its staid engines didn't do justice to its cars' advanced designs. This was less of a problem in a sedan like the DS, but an opulent GT machine like the SM would have made no sense without a suitably charismatic engine. The Maserati V6 helped turn the SM into a world-class grand touring car that supplemented a signature Citroen package with some bought-in Italian charm.

And yet, for all its strengths and innovations, it somehow comes as no surprise that the SM sold poorly. The SM was a great car, but it just wasn't what people wanted. The styling was exciting but not sexy. The performance was competent but not exhilarating. But perhaps the car's biggest shortcoming was no problem of its own. The people who buy, and bought, lavish GT cars want to be seen when they arrive. Competing cars from more prestigious brands like BMW and Mercedes-Benz surely hurt SM sales, particularly in the brand- and image-conscious American market. When a BMW pulled up in front of a restaurant, passers-by saw a successful person. But when a Citroen SM pulled up behind, people only saw a funky car—one that, for many onlookers, probably looked more like a submarine or a humpback whale than a traditional grand tourer.

Even if a large market had existed for a car like the SM, though, the grand touring Citroen still had some unflattering traits. Its hydropneumatic suspension/steering/braking would have been known well to Citroen shops the world over, but the short supply of Citroen mechanics in America ensured that an SM would never be as reliable or affordable to service as its more common competitors. Additionally, many buyers may have scoffed at the Citroen's front-wheel-drive, and still more likely preferred the flatter cornering of more stiffly-suspended competition.

Over a half-decade of production, Citroen produced just under 13,000 examples of the SM. Following the oil crisis of 1973, the carmaker ran into great financial difficulties and in 1974 Peugeot absorbed Citroen. The following year, the new Peugeot-Citroen group sold off Maserati to Alejandro DeTomaso. A strange era had ended, taking with it one of the most exciting and belligerently individualistic Citroens ever created.

Sources:

'Citroen SM Buyers Guide.' Citroen Concours of America. n.d. n. page. Web. 5 Jun. 2012. http://www.citroen-ca.com/SMguide.html.

Koch, Jeff. 'Cammer Chameleons.' Hemmings Sports & Exotic Car. Feb 2012: 18-25. Print.

'Maserati's History.' Maserati. n.d. n. page. Web. 5 Jun. 2012. http://www.maserati.com/maserati/en/en/index/passion/company/history/recent-years.html.

by Evan Acuña