2000 is the thirtieth anniversary of the launch of the GS and SM 

Thirty years ago, Citroën's range was perceived as being dated.  The 2CV and DS had both been around for what seemed like an eternity.  Despite the introduction of the Ami 6 and later the Ami 8 , there was a yawning chasm in the range where Renault , Peugeot and Simca had the market sown up.  The 2CV had been face-lifted and had acquired more power but was facing stiff competition from the Renault 4 and the Dyane , while being less rustic was still perceived as being little more than a tarted up 2CV.  The DS had also been face-lifted and had also been given more power and although it may seem strange from a modern perspective, was seen at the time as being old fashioned compared with newcomers like the Renault 16.  If the DS21 offered more power than lesser models, it was clear that the chassis could handle considerably more power.  For years rumours had abounded about a high performance variant of the DS - the so-called Véhicule S or D Sport but that was all that they were - rumours.
Both Peugeot and Renault had adopted front wheel drive and their products were seen as being fresh and modern.  The reputation of the DS had received a boost in the 1968 London to Sydney Marathon even if a cruel twist of fate had deprived them of victory.  In 1969, the range was revamped with new dashboards and new names but the marque lacked a truly prestigious "haut de gamme" model.

In 1970, all this was to change.  Citroën launched not one but two new models and re-established its reputation as a manufacturer of technologically advanced motorcars.

Throughout the sixties, Citroën had worked on a mid-range vehicle - and one of the prototypes, the C60 has been preserved by the company.  C60 would have had hydropneumatic suspension, a flat four air-cooled engine and employed a body design by Flaminio Bertoni which drew on both the DS and Ami 6 for its styling.  For reasons that are still not clear, this project was abandoned and a new one, Véhicule F was proposed.  In order to meet the design criteria, two different models were developed - a torsion bar sprung version with a flat two or flat four air-cooled engine and an hydropneumatically-sprung version with a twin rotor Wankel engine.  Both vehicles employed a novel means of attaching the roof to the structure of the car and shortly before launch of the new model; Renault went ahead and patented the system.  There were suspicions of industrial espionage and Véhicule F was abandoned at the very last moment.  The Renault 16 which employed the patented roof structure was launched to widespread acclaim.  Not only did it use the technique developed by Citroën, its styling was also very similar to that of Véhicule F – including the hatchback.  Billions of Francs of development costs were written off and the replacement car, Projet G was designed and built on a very tight budget and in a very short timescale – F was cancelled on 14 April 1967 and the GS was launched on 24 August 1970.

Véhicule S started life as a sports version of the DS.  A number of wildly different prototypes were built although they all shared a common architecture based on that of the DS - front wheel drive employing a mid-mounted engine with the gearbox in front, hydropneumatic suspension and two door body.  Engines were based on the Sainturat design but with five as opposed to three crankshaft bearings and twin carburettors and even a 16 valve version.  Power outputs were in the region of 125 to 130 bhp offering top speeds in the region of 200 kph.  Some of these engines were worked upon by Maserati with whom Citroën had signed a cooperation agreement in 1966.  In 1968 Citroën acquired a controlling interest in Maserati and the Italian firm was instructed to design a sub 15cv engine to power Véhicule S.  A number of prototype D coupes were built, powered by a V6 Maserati engine.  Signor Dottore Alfieri had removed two cylinders from the legendary 4 146 cm3 Maserati Indy V8 and reduced the bore and stroke to achieve a 2 670 cm3 V6. 

With the death of Flaminio Bertoni in 1964 the Bureau d'Etudes was headed by Robert Opron who was tasked with designing the bodywork for both new models.  Opron had been responsible for the design of Véhicule F and many of the styling cues of that model were carried over to the Véhicule S - the kicked up rear wing (also employed in the XM) and the headlamp designs.  Opron was ably assisted by Jean Genet in this endeavour.  For Projet G, Opron was inspired by some Pininfarina designs for a replacement for the BMC 1800 "Land Crab".  Projet G was overseen by Paul Magès - the man responsible for the DS? hydraulic system.

The design specification for Projet G demanded  a 6 or 7cv engine and hydropneumatic suspension.  There was also to be provision for a Wankel-powered version.

In the final event, 1970 saw an impoverished Citroën launch the GS and SM . With the acquisition of Maserati, the decision was taken to redefine the project with the accent being less on sport and more on luxury and prestige and thus the SM was a Grand Tourisme car in the pre-war tradition of marques such as Delahaye, Panhard , Delage and Bentley - a comfortable, high-speed tourer capable of continent-devouring journeys.  With the demise of Facel , France had no prestigious car to compete with the likes of Mercedes or Jaguar.  As the world's most powerful front-wheel-drive car, it offered novel solutions to the problems of torque steer.  Unfortunately the SM was compromised by a punitive domestic fiscal régime which meant that instead of the V8 and four litres that it cried out for, it was fitted with a V6 of under 3 litres.  A big, heavy car, it was still capable of spirited performance.  The original intention was for the car to also be fitted with the four cylinder from the D Series and for a four-door version to be built - the intention being to replace the top of the range D models.  Sadly this was not to be - the SM was killed off in 1975 by a combination of escalating fuel prices, the imposition of speed limits and the unimaginative leadership of Peugeot.

The GS on the other hand had a long, distinguished career.  Winner of the Car Of The Year Award, it beat the SM and set the mould for most of today's medium-sized cars.  In an era when the average medium car used rear wheel drive, cart spring rear suspension, drum brakes and had the aerodynamics of a house brick, the GS came as a revelation.  Front wheel drive was of course de rigueur.  Housed in a completely new and modern body with unparalleled aerodynamic efficiency, the GS looked like a hatchback but was in fact a saloon.  The body styling was obviously Citroën and yet it owed nothing to any of its forebears.  It used hydropneumatic suspension and the fully powered braking system of late model IDs but with discs all round.  That beautiful aerodynamic body was not there purely for aesthetic purposes but also served a practical purpose.  With a displacement of just over one litre, this car offered the kind of performance more normally associated with cars with a 50% bigger capacity.  Top speed was 92 mph - not far short of the D Spécial and the 0 to 60 dash took approximately 16 seconds.  The Achilles' heel of the car was its fuel consumption which hovered in the low twenties if driven with enthusiasm.  Once again, the French tax régime was responsible for a small engine working very hard. 

The engine itself was a real jewel - a flat four, air-cooled, twin overhead cam unit, it has been described as a "miniature Porsche" and like the Porsche boxer, it thrived on revs.  The torque curve was almost a straight line with a doubling of revs resulting in a doubling of torque.  This meant that there was a lot of gearchanging required and those who had feared another quirky dash or column or worse still, powered gearchange were delighted to discover "four on the floor" - although a three speed "convertisseur" was available as an option.  The floor mounted change was easily achieved by mounting the gearbox behind the engine in 2CV fashion.  Air-cooled cars are notoriously noisy and special attention was paid to this aspect of the car - to the extent that it actually became quieter the faster it was driven.

Another concession to normality was the brake pedal.  Gone was the mushroom of the DS (although it was retained for the SM) and in its place was a perfectly normal pedal.  The modus operandi was pure D Series - fully powered from the hydraulic system with the pedal merely opening a valve.  Where the shank of the pedal was concealed beneath the floor on the D and SM, on the GS it was visible.  And strangely enough, this made it acceptable to the motoring public - I say "strangely" because I don't know anyone who actually looks at the pedals while driving. 

Front brakes were inboard just like the D, the A series and the SM.  The parking brake operated on the front wheels in time-honoured Citroën fashion and once again, those who had feared another foot-operated "handbrake" were delighted to encounter an easy-to-use handle mounted in the middle of the futuristically sculpted dash .  The dash itself, designed by Michel Harmand, drew on Bertoni's original design for the DS, swooping upwards to encompass the instrument panel which contained a boomerang-shaped tachometer and a digital (but analogue, not electronic) speedo.  Other interior innovations included separate hot and cold air volume controls which permitted hot air on your feet and cold air on the screen (or vice versa or any mixture of the two) and a vertically mounted radio in the centre console which also housed the ride height control.

Steering was unassisted but thanks to the inboard front brakes featured "centre point" geometry whereby the pivot point passes through the centre of the tyre footprint.  This allows the car to run true, irrespective of road surface, camber or even a flat tyre and was pioneered in the 2CV and carried forward into the D and SM.

Ride was superb - more heavily damped than the D, it was clearly a second-generation version of the hydropneumatic system since roll was greatly reduced.  Handling in the dry was irreproachable, given the performance envelope and while there was clearly a deterioration in the wet, this was largely to do with shortcomings in the tyres that were then available rather than any flaws in chassis design.  An understeerer in extremis, it was safe and predictable and set new standards in its class. 

By the time the GS made it to these shores, the strange instruments had been replaced by conventional round ones.  In the conversion to right hand drive, the parking brake was left unchanged which resulted in a considerable loss in ergonomic efficiency - the release button which in left hand drive form was operated by the index finger of the right hand fell to the little finger of the left hand or required the hand to be turned palm up to allow the index finger to operate it.  Wipers remained set up for left hand drive too.  The vertically mounted radio was also a disaster; the passenger was faced with an upside down display and when cassettes became popular a few years later, the location guaranteed that dirt would find its way into the mechanism.  Many radio cassette units would not operate vertically either.

But none of these quibbles detracted from the driving experience and it would be ten years before the competition could develop cars that rode or handled as well as the GS - with the exception of the AlfaSud which used a very similar layout, albeit with a water-cooled boxer engine and steel springs.

Only three other body styles were offered - a five door break, a three door panel van and a three door glazed van.  Power was grudgingly increased, first to 1.2 litres and eventually to 1.3 litres.  The original 1.0 litre engine was replaced by a 1.1 litre unit.  These revised engines offered little in the way of extra performance but improved on both emissions and economy.

847 Wankel-powered Birotors were built in 1974 and 1975 but the oil crisis that killed the SM also led to the demise of this car.

Three "sports" versions were introduced - the GS X with initially the 1.0 litre and later the 1.1 litre engine and a close ratio gearbox, tombstone front seats and auxiliary driving lights and painted black bumpers.  The short gearbox made the car marginally more lively but the "tuning" was essentially visual.  Both these cars were fitted with conventional round instruments.

The GS X2 was similarly equipped but had a slightly more powerful version of the 1.2 litre unit and the close ratio gearbox and this was eventually superseded by the GS X3 with 1.3 litre power unit and was the first GS to reach a maximum speed of 100 mph.

The new 1.3 litre engine went on to power the GSA - introduced in 1979, it represented the first major restyle of the car - front and rear bumpers were changed to plastic ones and the car finally became what it had always appeared to be - a five door hatchback.  In X1 and X3 form, the GSA was the most aerodynamic family car of its era with a CDs of 0.30 - a figure eventually matched only by the Audi 100. A five speed gearbox was standard on all but base models.

The GSA was superseded in 1984 by the base model BX but the engines lived on until 1996 in the Oltcit/Oltena Axel .  The GS engine had also been used in the Ami Super , the MEPX racing cars and the BFG Odyssée motor bike.

Although the base BX and bigger engined Visas were meant to fill the gap, it was not until the advent of the ZX that Citroën once again sold a car in this market sector.  Gone was the hydropneumatic suspension and the powered brakes, gone too was the superbly aerodynamic body but on the plus side, the ZX is far quieter, more economical and safer than the GS. 

But if the GS' technology was not adopted by other manufacturers, it is still fair to say that it set the scene for good handling medium-sized cars and all today's hot hatches owe it a debt of gratitude.  Vauxhall/Opel's last Astra but two even borrowed some of the GS' styling.  The SM on the other hand was something of a technological cul de sac although the XM borrowed some of its styling cues and of course its name was reminiscent of its forebear too.

The GS was built in Belgium and under licence by Tomos in Jugoslavija where it was fitted with four round headlamps.

The SM is rightly acknowledged as a classic but the GS has been largely ignored and yet it is this latter car that was the more influential and commercially more successful.  In this, the thirtieth anniversary of its launch, let us hope that the media picks up on it and that it is eventually afforded its rightful place in motoring history.