AT-A-GLANCE: Bigger engine and higher gearing make technically impressive car much more relaxed. Performance and fuel consumption both markedly improved; ride and handling to the same high standard, brakes slightly disappointing. Many detail improvements inside.

TO some extent, we seem now to have become used to the Citroen GS. Judging by the number one sees on Britain's roads, plenty of buyers have accepted its extreme individuality for the sake of its aall-round performance and comfort.
In its original form, the GS had one distinct drawback, and that was the small size of its engine. This was dictated by the French taxman?s interest in puissance fiscal, and the average French owner must have been delighted that the car would do as much as it did on 1,015c.c. capacity. But the British had no advantage to compensate for poor acceleration allied with surprising thirstiness - the latter an invariable sign of a power unit too small for its car.
Even at the time of the GS introduction, Citroen claimed that the air-cooled, flat-four engine was capable of being stretched to give 1,300c.c. capacity. In fact they have not gone quite so far, but have enlarged both the bore and stroke to give 1,22Oc.c. This is still, in conventional terms, a small engine for a car the size of the GS; but it is over 20 per cent bigger than it was, and both power and torque have increased in something like proportion.

Improved performance

On the road, one immediately notices the extra performance of the GS 1220. The bigger engine has more punch, although it is not appreciably more flexible; it is unwilling to pull from much under 20mph in top. Once under way, however, the flat torque curve shows, to good effect. One is much less often reduced to changing down, or to using full throttle to keep up with the rest of the traffic.
Part of the impression of greater relaxation is due to higher gearing. The GS 1220 has two fewer teeth (33 instead of 35) in the crown wheel of its final drive, raising the overall gearing to 15.25 mph per 1,000 rpm. This is still by no means a high figure, but the Citroen engine is a high-revving unit developing its peak power at 6,500 rpm.
In view of this figure, it is perhaps surprising to find the red line on the rev counter at 6,200rpm. When testing the 1015 version-an early car with no rev counter-we admitted to using 8,000 rpm, so clearly the red line does not represent the mechanical .limit. As in several other cases, the red line can be taken as the maximum continuous limit, and we have used 6,500 rpm when computing the maxima in the intermediate gears. These are still relatively low; first will not pull 30mph, nor second 50 mph. Third gear takes one past 70 mph, leaving something of a second/third gap.
The mean maximum speed of the GS 1220 is 94 mph, which is 4mph faster than that of the 1015. With the revised gearing, 94mph corresponds to just under 6,200 rpm, underlining our point about the red line. The car seems happy to cruise at this speed almost indefinitely, though a downward gradient can easily give sufficient help to put the rev counter well into the red.
It is, however, the improved acceleration which is likely to be of more interest to 70-limited British motorists, and here the 1220 scores strongly. Its superiority shows at every speed in every gear, becoming more marked as speed increases. In our standing-start acceleration runs, the time taken to 30mph came down from 5.8 to 4.4sec - explaining perhaps more than any other figure why the 1220 is so much less of a strain to drive in city traffic.
Energetic standing starts provoke the front wheels to hop slightly as they spin, rather in the manner of the big Citroen Ds, though not as violently. Once the 1220 is underway it carves seconds off each of the 1015╒s times, reaching 60mph in 14.9sec as against 18.0, and 80 mph a clear 10sec sooner. In the calm test conditions, we were also able to record a time to 90 mph.
Our comparison tables put the 1220 into perspective, showing it to out-accelerate the Fiat 128 and Peugeot 204, and by no means lagging far behind the higher-powered Renault 12TS and Simca 1100 Special. Its maximum speed, thanks to its good aerodynamic shape, is very much on a par with these last two. In so far as it loses ground at all, it is still in the first few yards away from the rest, and this shows in the relatively slow time to cover the quarter-mile. This is the only respect in which the GS 1220 could be called slower than average, but it does suggest that an even more powerful engine would give it first-class performance.

Gains in economy

There is a good deal of evidence to suggest that the more seriously underpowered a car, the more its fuel consumption suffers. Our results for the 1220 seem to back this up, for it proved more economical than the 1015 both overall and at almost any steady speed. The steady-speed gains were not large except at 30 and 40mph, and decreased steadily until at 80 mph it was actually using slightly more fuel.
In overall terms, the 1220 managed 24.8 mpg compared with 23.3 mpg for the 1015, reflecting as much as anything the far smaller part of the time which the larger-engined car spent with the accelerator pedal flat on the floor. Its best brim-to-brim consumption was a creditable 29.4 mpg, achieved with the sort of driving in which a typical, fairly gentle owner might indulge. On the other hand, the GS is still not as economical as some of its rivals, as our comparisons show, and it may well be that a further increase in engine size would bring a benefit in this direction beyond what has already been achieved.
For a car with a moderate overall fuel consumption, especially one so well suited to motorway cruising, the Citroen?s fuel capacity of under 10 gallons means a rather limited range. The test car used hardly any oil while we were driving it.

Handling and brakes

Apart from the bigger engine, there have been no fundamental changes to the GS since its introduction was so widely acclaimed; the hydropneumatic suspension, with the front and rear units interconnected to permit self-levelling, remains the same. So does the combination of comfort and handling which it confers.
The first thing noticed by most drivers is the lightness of the steering, which is quite remarkable in a big, front-drive car with all but two-thirds of its weight on the front wheels. Nor is there any sign of its having been achieved at the expense of anything except rather low gearing, with nearly four turns of the wheel between extremes of a 33 ft lock.
This low gearing is only noticeable in town, or where a succession of corners have to be negotiated at low speed. At other times the effect is disguised by the Citroen?s near-neutral handling in gentle driving. This in turn adds to the feeling of precision about the rack and pinion steering, and means that the car responds quickly to any movement of the wheel.
Despite this agility, there is no sign of the car needing to be held on a straight course. Its natural stability is excellent, and is especially welcome on motorways. Sidewinds affect it very little.
When driven hard, the Citroen begins to understeer, running wider and wider of the chosen line as the power and weight bias take charge. It is all very progressive and predictable, and very little untoward happens (other than a slowing-down) if the driver panics and brakes in mid-corner.
The supple suspension keeps all four wheels on the ground more of the time, perhaps, than in any other car, and this shows up in _the truly remarkable road-holding. There is some tyre squeal in extreme situations, but the combination of grip and control enables corners to be taken at speeds which would confound a traditional sports car - more so on mediocre surfaces. Indeed, with its extra power, we had the feeling that the GS showed some potential as a rally car.
The only cautionary note which has to be sounded is that there are limits, even for the GS. It is ultimately dependent on the grip of four patches of rubber, and they will not hang on for ever. When that limit is transgressed, the front wheels let go first and the car ploughs straight ahead, recovering when the accelerator is released.
The brakes take a bit of getting used to, since the movement of the pedal is small and the effort needed is light. A driver coming fresh to the car from something more conventional tends at first to stop too quickly and jerkily; with practice, one realises that a little finesse suffices to bring the car to a stop with excellent and progressive control. On a damp surface, we were unable to match the remarkable ultimate stop achieved by the original 1015 test car, but still managed O.9g before the front wheels firmly locked, for a pedal pressure of 50 lb.
In our fade test, the 1220 fared rather better than the 1015, with a smaller rise in pedal effort required for a O.5g stop. After the fourth stop, the brakes behaved more or less consistently, with no further increase in effort. Despite its peculiar merged with-the-facia handle, the handbrake (which acts on the front discs) works well, giving a good emergency stop on the level and holding either way on the 1 in 3 test slope. Unlike the 1015, the 1220 was able to manage a restart on this gradient, though not without a slight smell of clutch lining.

Fittings and furniture

The front seats look fairly well shaped, but it is not until one actually sits down that their location and support become apparent. The cushions are soft, allowing their occupants to sink an inch or so; the backrests are firmer, relying more on curvature to provide sideways support. Nylon cloth upholstery gives an air of added comfort, and is pleasantly warm in winter.
Though they have no centre armrest, the back seats are almost as comfortable as those in front. The cushions are not quite so deep, presumably in the interests of easier exit. Thanks to the fastback styling, which extends the roofline well back, there is as much headroom as in the front seats. Knee room is also generous, emphasising that the GS is a big car and should be regarded as such, rather than being classified purely by engine size. The back seats are sculptured into two separate places by the shaping of both cushion and backrest, but there is sufficient width for three passengers if they are smaller than average.
The Citroen's ride is above all the things that singles it out from the competition. There would be no point in having the complicated hydropneumatic suspension unless it combined soft springing with superb damping; but this it does, with notable success. On a smooth road, it feels like any car with good, conventional suspension; slightly under-damped, perhaps. In corners, the car rolls no more than its main French rivals.
As the road surface deteriorates, so the Citroen?s advantage becomes greater. It spurns single bumps or potholes, and it is far from easy to get the car into phase with a series of undulations. If one succeeds, the back end of the car can start to bounce higher over each crest. Over really bad, broken surfaces the Citroen is impressive in two ways; for the insulation which it continues to afford its passengers, and for the way it remains controllable and stable.
The steering wheel with its imitation leather rim is quite small, and set at the right height for an average-to-tall driver. For a front-drive car, the gearchange is not at all bad; slightly notchy, but positive, requiring moderate effort and having a reasonable travel between gears. There is a light spring loading towards the third/fourth plane, but not so much as to interfere with down-changes. The pedals are nicely spaced, with a small offset towards the centre of the car. The clutch is light enough to match the brakes, but its take-up is rather abrupt.
Most of the minor controls take the form of short stalks behind the steering wheel, leaving only the push-on switches for the heater blowers and the heated rear screen. Both the ignition lock and the choke are well concealed below the facia. British - market GSs are equipped with proper round instruments, and are apparently the envy of the French, who have to put up with a stylized horror of a facia. In the 1220, the rev counter reads up to 8,000 rpm, but the speedometer to only 100 mph - which, with the instrument's optimism, means that one can end up "off the clock". In the manner of many French cars, the fuel gauge wavers badly when the tank is less than half full.
The heater controls are logical, though not very easy to reach if one is securely strapped in. Two vertical slides control the flow of hot and cold air, and a single horizontal slide takes care of the distribution. It is, however, rather difficult to select exactly the right amount of heat. Ventilation, via face-level fresh air inlets, is good, and the heated rear window works well.
When driven gently, or even when cruising fast, the Citroen is commendably quiet. It is only when accelerating hard, or at the very highest speeds, that the engine starts to thrash and interfere with normal conversation. There is only a little transmission whine, and road noise is good except over some types of bound-gravel surface. Wind noise is well suppressed, and there are no boom periods, though the facia area vibrates slightly when the car is flat out.