The Citroen SM
The best of two worlds
The people behind the design and construction of Citroën cars are seldom, if ever, referred to by name, and in their own publicity material Citroën refer to "engineers in Citroën's research division". Little is heard about the research and development department of Citroën cars, and even less about the design department. The whole firm must be chock-ablock with brilliant designers and engineers, for Citroën cars have stood out on their own in the world of automobile design for as long as one can remember. You either believe in Citroën engineering or you are content with the standards of Dagenham, Luton or Detroit. If you believe in Citroën you will have accepted the "Traction Avant" in the mid-thirties, the DS series in the mid-fifties and you will certainly believe in the SM, which is, surely going to carry Citroën through to the mid-eighties. When the DS appeared in 1955 there were those who detested its looks, were nervous about its road-ability, frightened of its apparent complication and refused to adapt their conventional driving style to the new-style demanded by the DS. These people shied away from the new Citroën and kept other, more mundane car manufacturers in business. Those who believed in Citroën approached the DS with an open mind, like I did at the time, and were truly staggered by what they discovered. Here was a car that was way ahead of all its competitors in the saloon car category and had remarkable powers of cornering, ride and average speed when driven enthusiastically. It was a triumph of production engineering, apart from a triumph of design, and some years later when testing another make of large front-wheel-drive family saloon I began to enthuse about it with the Editor when we stopped short and realised we had said it all in 1955, nearly ten years before, and all this new model was doing was catching up to where Citroën had started.
Not being a "family motorist" I never had any desire to own a DS Citroën, but always appreciated those who did, in all countries throughout Europe, and enjoyed many happy "dices" with enthusiastically driven ones in France or Italy. Over the years, when talking about cars and car design the DS Citroën would invariably crop up and we would try to visualize what Citroëns' replacement would be. Even in 1965, ten years after the introduction of the DS, we could not see any signs of what the next Citroën was going to be like, but having faith in Citroën engineering we were sure it was not only going to be exceptional, but as far in advance on engineering as the "Traction Avant" was and the DS was. As the decade of the seventies began the Citroën SM appeared and to Citroën believers it was no disappointment. An inkling had been given by the fact that Citroën had bought the firm of Maserati at the beginning of 1968, and though a certain amount of noise had been made about Wankel engine research, Maserati enthusiasts in Modena could be heard muttering about "French engineers crawling about all over the place" and some hardened Maserati workers left the firm as they could not stand the pressures being exerted by the French engineers. The Citroën for the seventies was powered by a Maserati engine which put the French firm in the high-performance category for the first time, for until then engines were not the most exciting thing about Citroën cars.
For the past two years I have been wandering about Europe "drooling" over the SM Citroën, at first only catching the odd glimpse of one now and then, and later as production got under way I was able to get closer to them. I can recall the first time I saw one parked by the roadside; I stopped and went back to enjoy being in the presence of such a beautiful looking piece of machinery. It was only recently that I was able to fulfil a great desire to drive one, and the two years of waiting have been more than worthwhile. In Great Britain Maserati cars are handled by Citroën at Slough, not far from London Airport, and last year I went there to borrow a Maserati Indy and the poor man who was lending me the car had an awful job getting me into the Indy, for on the other side of the garage was a Citroën SM. I just felt that one car was the end of an era and the other the beginning of a new era, and I had no regrets for the passing of the old and could not wait to experience the new.
Even in the exotic automobile surroundings of Monte Carlo and Nice the Citroën was beginning to make everything else look obsolete or peculiar and when I saw one among Lamborghinis and Ferraris I had to tell myself that it was not a one-off "dream car" or small production model, like the Italian cars, but was in mass-production. Last year, in a Letter from Europe, I mentioned how I had a little dust-up at 125 m.p.h. in my E-type Jaguar with a Citroën SM on a French Autoroute, and how it impressed me; that was the first time, and there have been others since. This year Mike Hailwood has been using a Citroën SM for motoring about Europe, he being one of the rare breed of Grand Prix drivers, like Niki Lauda and Ickx, who enjoy motoring for its own sake. The fact that Hailwood was still using his SM at the end of the season spoke volumes for the car, for he is not one to tolerate something he does not like and can afford to have any car he wants. The aura of the Citroën SM was growing all around me and when Citroën finally let us have one on loan for two weeks I could hardly wait to get in it. In spite of the glowing things that knowledgable colleagues said of it, I was fully prepared to be bitterly disappointed, especially when other people said how they did not like it. To say that the SM lived up to all my expectations, and more, is to understate the case. It rates at the very top of my list of desirable cars, even above the Dino Ferrari, which I rated as the ultimate in sports cars. The SM is even more than that, it is the ultimate in serious motoring, and by that I do not mean a dash up the road and back, or making a high average from A to B, or extracting the maximum enjoyment from driving. It is all of those things, but above all a car to live with, day in and day out, a car to use all day and everyday, under every type of going, fast or slow, but essentially for motoring with a capital M.
Having rated the SM that high I should now justify it, which will not be difficult, especially as I have long been Citroën biased as far as design and engineering are concerned. As regards the looks of the SM our full-page colour photograph in the October issue will determine whether you like it or not. Citroën say "The bodywork has been designed in a wind tunnel and has literally been sculpted by airflow. Its profile of glass and steel has been freed of sharp edges and flat and angled surfaces which are important contributory factors of resistance to forward movement". They go on to say "Conceived by the styling department of Citroën's research division from functional data, the shape of SM makes no concession to fashion. Its aesthetics have been rationalised and are the direct result of study of logic and reason." Some people "nit-pick" about this detail or that detail, others compare it to a Dino Ferrari or a Jaguar, but I think this is pointless. There are many very beautiful looking cars and for me the SM is one of them. Mechanically you either look upon the SM as a nightmare, and drive off in your Crootmobile, confident in its sound and proven engineering," or you open up all the apertures and regard the engineering with a glow of satisfaction. Everything that Citroën pioneered and developed on the DS has gone into the design of the SM, and more besides. Needless to say all four wheels are independently sprung, on a trailing-link geometry, and suspension is by the proven hydra-pneumatic, self-levelling, constant ride-height system perfected on the DS. Brakes are power-operated discs all-round, the front ones being mounted "inboard" on each side of the 5-speed gearbox, for the SM is front-wheel-drive, as all Citroën's have been since the mid-thirties. The power-operated brakes have two independent circuits and braking effort distribution according to the load carried. Steering is also power-controlled and the self-centering action is achieved by the same hydraulic power source, and this power control varies according to the car's speed. The hydraulic power system also controls the battery of six headlights, keeping them level no matter what the load in the car is, or the attitude angle of the car under braking and acceleration. The heart of the car is the Maserati engine, especially designed and built by Maserati for the SM. It is a V6 of 90-degrees with bore and stroke of 87 x 75 mm. giving a capacity of 2,670 c.c. (French taxation has a savage demarcation line at 2 litres), and it develops 170 b.h.p. DIN at 5,500 r.p.m. and 170.ft./lbs. torque at 4,000 r.p.m., with a usable peak of 6,500 r.p.m. There are four overhead camshafts, chain driven, and a four bearing crankshaft, and with an overall length of 12¼ in. it can be appreciated that the bottom end is rigid. The car on loan had three downdraught Weber 42DCNF carburetters, but fuel injection is also available. All the engine castings are light alloy and the cylinder heads are identical and therefore interchangeable, and this neat and tidy looking power unit is mounted well back from the front wheels, almost under the windscreen. In front of it is the Citroën 5-speed and reverse gearbox, with very large disc brakes on each side, with additional calipers for the handbrake and above it an open jack-shaft from the front of the engine drives the power pump for the hydraulic systems, and the alternator. The oil reservoir for the hydraulics is on the left of the engine compartment and this supplies the self-levelling suspension, the steering, the brakes and the headlight control.
Although the SM looks like a 2-seater GT car, it is actually a 4-seater with more than room for legless dwarfs in the rear, for having all the mechanism "up front" means plenty of depth in the rear and with the front seats fairly high off the floor pan, there is good leg room in the back. It is not a 4-seater in the saloon car idiom, like the DS, but is a 4-seater in the GT idiom. The front seats adjust in all directions except sideways, and the headrest adjust up and down and fore and aft so that they can be used, and are not just tiresome adornments waiting for the car to have a head-on collision. The scuttle is assymetrical, with all the dials and controls on the driver's side and the small oval steering wheel can be adjusted up or down and in or out. The whole column-surround adjusts with the wheel, so that the disposition of the various column control stalks remains constant to the wheel rim. The left-hand operates two controls, a short one which moves up and down for "winkers" and at the same time can be pushed forward to flash the headlights or pulled backwards to sound the horn. The longer stalk is for the wipers, position one being for intermittent wipe, starting off with 8 or 10 quick wipes and then one every now and then and position two gives continuous wipe, while pulling the stalk towards you actuates the squirts. At the right-hand finger tip is the lamps control, like all Citroëns, switching side, heads, dip and spot lights all on one control. You push the lever forwards for dip and this can be done with the knuckle of the second finger, and returned with the same finger. The driver has a tachometer and speedometer in front of him and slightly to the right is an all important circular dial divided into fourteen segments, thirteen of them indicating that all is well with some auxiliary. These cover oil pressure, alternator output, fuel reserve, headlamps main beam, indicators right and left, front brake pad wear, water temperature, hydraulic brake pressure, handbrake "on", rear window heater, sidelarnps and "hazard" warning. The fourteenth segment is actually a button, which you press to check that all the vital indicating bulbs are alright. In the centre of this dial is a master lamp, that shines bright red with the word STOP in the middle of it if anything is not functioning. When you switch on the ignition this sinister red lamp glowers at you until you start the engine and oil pressure, alternator, and hydraulic pressures start functioning. If it does not go out you switch off and call a Citroën mechanic. Similarly, if it should come on while you are motoring you stop at once because it means something has gone wrong. Having all this lot in one dial makes it very easy to check everything. In the centre of the scuttle is a clock, dials for water temperature, oil temperature and fuel tank contents, and below are simple, but comprehensive heater and cold air controls, while between the seats are the handbrake and controls for the electric windows. Also there is one of the nicest controls in the whole car, the gearlever. It is incredibly rigid and positive and a joy to use, for the five ratios are beautifully matched to each other and to the torque characteristics of the engine. The lever movement is long, but delightful to use and you change gear continuously for the sheer pleasure it gives. The lever is spring-loaded to the centre of the large gate, opposite positions for 3rd and 4th. To the left are 1st and 2nd and to the right are 5th and Reverse, 5th being a proper ratio and not a Motorway overdrive. It's position is to the right and forward, while 4th is central and back, and bearing in mind this is a left-hand drive car, the change from 5th to 4th at any speed under 100 m.p.h. is sheer joy. If the SM is built with right-hand steering this pleasure will be lost. Using 6,500 r.p.m. in the gears the SM gets up and goes in a fashion that caused more than one passenger to say "Citroëns are not supposed to go like this." The Maserati engine is a typical Italian thoroughbred, not smooth and silent, like a V12 Jaguar, but harsh and eager and becomes happier as the r.p.m. rise until it is humming round like a dynamo, like a Dino Ferrari or a Porsche 911. As you change gear at 6,500 r.p.m. the power is right on in the next gear, and so on up into 5th. The gearing is my idea of perfect for road use, for the SM will pull 6,000 r.p.m. in 5th gear (130 m.p.h.) so that you have 500 r.p.m. in reserve for "overwinding" downhill or with a following wind on an Autoroute. Normal relaxed cruising is 5,000 r.p.m. (106 m.p.h.), while high cruising is 5,500 r.p.m. (117 m.p.h.) and Citroën claim an all-out maximum of 220 k.p.h. (136 m.p.h.). It is a car that is just as happy at over 100 m.p.h. as it is at under that figure, and driving hard it gave 19 m.p.g., though less use of the r.p.m. and the gearbox would give 22 m.p.g.
Anyone who would query the "ride" in the SM would show their ignorance of basic design and like the DS, the hydro-pneumatic controlled self-levelling suspension makes you wonder why other designs still mess about with coil-springs, torsion bars, and leaf springs. On the left of the driver's seat is a control for raising and lowering the static setting of the suspension, which is very useful for anyone living in the country up a rough track and this control is also used for lifting the car up onto its jack when changing a wheel. The cornering ability of the SM is incredibly high, aided by 195/70-VR-15X Radial tyres by Michelin, and on dry public roads it was not possible to find the limit of adhesion. In spite of all the mechanism at the front and the wide bonnet, forward vision was terrific,making the car very easy to drive at all speeds, while rear vision in the mirror was remarkable bearing in mind the almost horizontal rear window. A very satisfactory feature was the fact that the rear of the car is eight inches narrower than the front, a very desirable feature if you enjoy driving fast and close. The whole car is so full of interesting features that you could spend an enjoyable morning in it, without even driving it; such things as two-position "keeps" on the long, wide opening doors, the hinged rear-window that gives access to the luggage compartment with its cover to conceal everything when closed, the oddments container in the arm-rests, the warm-air vents to the rear passengers' feet, the swivelling spotlights that turn with the steering, the outer one shining on the centre of the corner and the inner one looking across the apex to the exit of the corner, the warm-air feed to the inside of the perspex box containing the lights, to prevent misting, and many more interesting "engineered" rather than "stylised" features.
I have left until last the Citroën steering, for in their own words "It is at least as big a step forward as the hydropneumatic suspension was when the DS was introduced in 1955." As the SM was designed as a GT car, for covering the ground from A to B very quickly, under all conditions and types of going it was felt desirable to have very high geared rack-and-pinion steering. This was done with a ratio of 9.4:1 (compared to 14.7:1 for the DS) which gives one turn of the wheel from straight-ahead to full lock, and as full-lock gives a turning circle of 34 ft. 6 in. between kerbs, it can he appreciated that steering wheel movements for all normal motoring are very small indeed. With the large Michelin Radial tyres power steering was essential, but Citroën engineers were not prepared to accept power control of the high geared steering for high speeds, so they designed an ingenious hydraulic system that gives full power steering when static, so much so that the wheels return to straight-ahead under their own power, when stationary, to minimal power at high-speed so that the steering is precise and accurate. This control is driven from the front end of the gearbox and varies in relation to the speed of the car. It is interesting to read the Citroën engineers' reasons for high geared steering "greatest ease of manoeuvring on winding roads, or in all instances where it is necessary to avoid an obstacle quickly, or whenever it is necessary to make a rapid correction to the trajectory of the car, as a result of the effect of an external force, such as a gust of wind, passing a large vehicle quickly, or the beginnings of a skid." They go on to say "it is an essential element of safety, for how many accidents have been caused because drivers were not able to exert the necessary effort at the steering wheel, or because they could not turn the wheels quickly enough due to low-geared steering." This is what is called "primary Safety thinking" and you hear similar talk at Porsche and Mercedes-Benz, and it is so much better than the Ralph Nader hysterics.
When stationary or when maneouvring at low speed, such as parking, the steering wheel can be turned with one finger, but the effort to move the wheels increases with the speed of the car and with the steering lock angle, the increase being greater when the wheels start to leave the straight-ahead position, and decreasing towards the end of the lock. The wheel of the SM is essentially something on which to rest your hands, and not something to grasp and wrestle with. Anyone not used to high-geared steering, either from vintage car experience or motor cycle riding, tends to start off in a series of swoops as they hang on to the wheel, but if you relax and let Citroën get on with it the SM steering is superb. The faster you go the more rock-steady it becomes, and like a Porsche 911 or a Dino Ferrari it is so steady and quiet and fuss-free at maximum speed that you feel you could use at least another 50 b.h.p. On very fast curves it really is outstanding for you make no conscious effort to change direction, a slight pressure on one side of the steering wheel is all you need and you "think" it through 100 m.p.h. corners rather than steer it through. Obviously the SM is meant for fast motoring, but equally it is an enjoyable car to drive slowly and dawdle about in, pottering down country lanes or along winding roads. It has that rare quality of being a nice car to be in at any speed, from stationary to its maximum, and the interior fittings and comfort are such that it would be a pleasant car to spend 12 or 15 hours a day in on a long European journey.
If you are not appreciative of Citroën engineering then you could probably find lots of things to complain about on the SM, or if you approached it as a family "fug-box" you'd complain about the glorious noise of the 4-camshaft Maserati engine, or the fact that you had a gear-lever that had to be used, and you would have awful trouble fitting your roof-rack or stowing the pram or the collapsible boat, but if you look upon SM as standing for Serious Motoring, you would enjoy it. Driving the SM I found nothing to complain about, but passengers taken on "demonstration" runs complained about the lack of sideways support afforded by the front seat, the obvious cure being for the driver to corner a bit slower, or alternatively to clamp the passenger in with a full seat-harness. The use of the word Safety-Belt would be a misnomer, for safety is inherent in Citroën designing and part of the basic conception of cars like the SM, in which accidents are of secondary consideration, the primary one being to design a car which is capable of avoiding an accident. I am sure Citroën engineers believe that the way towards safety is to avoid accidents and make sure the car will help the driver to do this at all times. Safety, performance and comfort were the three major aims behind the design of the SM, and there is no doubt that these have been achieved. Such perfection in design does not come easily or cheaply, and in Great Britain, as sold by Citroën Cars Ltd., of the Trading Estate, Slough, Buckinghamshire, the SM costs a minimum of £5,136, and by the time you have added to its "living quarters" with such things as leather upholstery, radio, air conditioning etc., the price could rise to nearer £5,700. On the road, taxed, insured, with all the extras and a full tank of petrol (20 gallons) there would not be much small change left out of £6,000, but you would have the ultimate in Motoring, and a real "Car of the seventies", that will no doubt carry through to the eighties while Citroën engineers work away at the next one and other manufacturers try to keep pace or struggle to catch up. It was one of the few cars I was really reluctant to return to its owners. — D. S. J.