Eighties Eco-Concept Marvels: Number 1 – Citroën ECO 2000

A short series in which we look at three small eco-concept cars from the 1980s and see what became of them.

ECO 2000 in museum context (Source: Auto.cz)

I was an eighties teenager and consider that decade to have been influential on many aspects of the world today. After what seemed to me to have been the grim stagnation, complacency and listlessness of the seventies, the eighties saw the (sometimes painful and tragic) breaking of ties to the past and the search to replace them with future opportunities, especially in technological innovation.

Like myself at that time, I would argue it that was a decade which could be described as naïve, one in which political, economic, cultural and social ideals and principles still meant something. People who believed in those ideals and principles were prepared to stand or fall on experimenting with their trust and belief in them.

I also perceive that the experimental activities of car manufacturers in the 1980s resonated to the drumbeat of those times. Following the second oil-crisis at the end of the 1970s, governments leant on their national manufacturers to develop super-economical cars for the masses. Given that average real wages were still relatively low and credit availability tight at that time, it was no surprise that lower cost, sub-compact and compact cars were most often the subjects for such experimentation.

It was through the pages of Car Magazine that I experienced a quite fantastic and exciting era of innovative and interesting looking small car concepts. I believe this experience nurtured my fascination with small cars, which I still think should, above all, display intelligence in their conception and development, although it’s also handy if they come to production as fun to drive and engaging in character.

A notable differentiator of the times was that, back in the ’80s, ‘eco’ was taken to mean ‘economical’ rather than ‘ecological’ as we would assume today, although there should obviously be a read-across from former to latter. The three eco-concept marvels I have in mind are; the BL ECV 3, the Renault VISTA, and, to get us off to us a brisk start, the Citroën ECO 2000. These contemporaries demonstrated both similar and divergent solutions to the challenge of reducing fuel consumption, solutions which would inform production cars of the future – at least that was the idea.

Rear view – note the shallow dip of the roof (Source: Read Cars)

The ECO 2000 was formally revealed at the 1984 Paris Salon. Like the other cars featured in this mini-series, it was not just a styling exercise, but a true, running experimental prototype. 50% of its cost of development came from French governmental research funds. The funding went to a joint Peugeot-Talbot-Citroën research organisation called DRAS.(1) Possibly because of this, it was clearly felt that its styling should not be attributed solely to Citroën (under Carl Olsen) and so was more anonymously accredited to a joint PSA design team.

DRAS was set a target to produce a car capable of fuel consumption of just 2 litres per 100km. The criteria also stipulated that the car should have enough room for four people to ride in comfort, for there to be adequate performance and roadworthiness, and for the car had to meet all known incoming legal and regulatory requirements.

The DRAS team developed three design proposals(2) before landing on the final version shown in Paris. The first was rear-drive and propelled by an air-cooled twin(3). The second had a three-cylinder in-line diesel and, as such, was deemed too sluggish and uncouth(4). The third prototype, completed in March 1984, possessed the best compromise within the design criteria and was quickly evolved into the definitive version of the ECO 2000, code-named SL 10.

Manufacturer’s fact sheet (Source: Citroenet)

Car Magazine reported that “This FWD four-seater…boasts an exceptional drag coefficient of 0.21, and weighs a mere 1,056lb [about 480kg]. It accelerates from 0 to 60mph in 18sec, tops 88mph and averages an incredible 80.7mpg. Among the car’s more interesting details are its revised Hydropneumatic suspension, a water-cooled 35bhp in-line three-cylinder petrol engine, a hydraulic four-speed gearbox, a tiny four-gallon petrol tank and low profile 140/65R290 TRX tyres with very low rolling resistance.” Note that the overall fuel consumption quoted by the magazine equates to 3.5 litres per 100 km, well shy of the target. However, the car reportedly did manage 2.1 litres per 100 km at a steady 90km/h.

According to further information published on the excellent Citroënët(5) website, the engine was a 750cc version of FIAT’s FIRE engine. The same source informs us that the suspension included electronic control of the ride height depending on the car’s speed. It seems stubborn of Citroën to have insisted on a Hydropneumatic suspension even though that would have come with a weight penalty (and engine efficiency losses depending on how the suspension was pressurised) on a car which was designed to be as light as possible in the name of fuel economy. That said, it sounds like it could have made for a small car that drove like no other.

A poor photo of the interior – but note, PRN Lunules! (Source: Citroenet)

Of course, the bits of the ECO 2000 that one can see are rather interesting too. As with the other cars in this series, it looks like aerodynamic work undertaken by at least two of the three manufacturers in question led to production cars of a fundamentally similar profile. The ECO 2000 is a three-door hatch and stands out for its two-box, ‘aero-bread-van’ shape, with a smoothly round-edged but vertical rear and featuring a roofline which slants downwards noticeably just beyond the line of the B pillar. It’s like a wide but shallow ski-slope and is clearly shaped from learnings in the wind-tunnel.

It’s also notable for a its deep and extensive glass-house, with a quite acutely curved screen and shallow window openings cut into the side glass so that the aerodynamics would be less disrupted when occupants open the windows. This latter solution is reminiscent of the Subaru SVX and Toyota Sera. From the leading edge of the door forwards, the car could well be one of Italdesign’s, a thought embellished by the notch along the lower edge of the DLO just at the leading edge of the door’s window opening.

The way in which the tops of the rear arches are flattened off (to align with a feature-line which rises from just aft of the doors and wraps around the lower section of the car) is the only real visual statement that the ECO 2000 is a Citroën. Citroënët attributes the styling to Scott Yu(6). Pictures available on Citroënët show a pleasant interior, with fun orange and grey fabrics on the seats and a dash featuring the delights of PRN-Lunules.

Overall, then, a lot to get excited about in terms of the potential for a production variant of this car.  As Car Magazine noted: “If the ECO 2000 is really the pattern the upcoming AX will follow, the ’86 baby Citroën will undoubtedly set new standards for superminis.”

The production AX – disappointing after the ECO 2000? (Source: Tumblr)

With that in mind, it’s not that surprising that the production AX, when it emerged in 1986, was received with disappointment by many. Apparently, more radical designs that were much closer to the ECO 2000 conceptually were rejected following poor feedback from customer clinics. In its October 1986 edition, Car Magazine reviewed the recently launched AX in a piece titled ‘Citroën’s Peugeot’ and stated that “…big brother Peugeot has quashed any sign of Citroën quirkiness.” At first look at least, the AX appeared utterly conventional and conservative in its styling.

Look a little deeper, though, and the low Cd of 0.31 was very good at the time for such a small hatch, while the car’s weight was exceptionally low at 640Kg for the base 954cc example. Both factors hold true to the objectives and achievements of the ECO 2000. Driven sensibly, the AX was notably more parsimonious than a 205 equipped with the same engine(7).

The AX’s suspension was steel-sprung, but was at least all-independent and possessed of longer wheel travel than was the norm, in the tradition of the 2CV which it was partially designed to replace.  The interior was basic and the lightweight plastics all too evident, as was the absence of lunules.

Overall, the AX was disappointing in the context of the ECO 2000.  As a former owner of an 11RE version, I can say that the AX had a great, zesty character, was excellent fun to drive, very economical, even with only a four-speed gearbox, and so got away with the obvious downsides of its lightweight build, which included poor interior noise insulation, especially from the gargling exhaust pipe. Well, at least it did on my example.

Today, the idea that Stellantis would develop and produce a small, ultra-light, gas/ fluid-suspended car with a semi-automatic gearbox is, of course, impossible on so many levels.  But, that still doesn’t stop me from wishing that it would.

(1) A prize to the person who can discover what DRAS stood for. I’m blowed if I can find it!

(2) Code-named SA 103, SA 109 and SA 117. Interestingly, SA 109 and SA 117 were sold at auction in 2017.

(3) It is unclear as to whether or not this engine was sourced from the 2CV.

(4) As anyone who has ever driven a VW Group car with an engine of similar format, for example, the Audi A2, can attest.

(5) I mean to pay Citroënët the highest of compliments when I describe the site as being to Citroën what AROnline is to British Leyland / Austin Rover / Rover Group and all of its other guises.

(6) I have failed to discover any more about Mr Yu.

(7) PSA’s TU rather than XU unit, and no three-pot version of the FIRE engine in sight. I wonder what happened there?

Author: S.V. Robinson

Life long interest in cars and the industry

32 thoughts on “Eighties Eco-Concept Marvels: Number 1 – Citroën ECO 2000”

  1. Recall reading claims the earlier 2-cylinder powered SA 103 version of the ECO 2000 prototype was actually water-cooled, yet for some reason thought it was a development of the 652cc Flat-Twin rather than a Fiat 126-sourced 704cc Twin.

    The French and Italian language versions of the Fiat FIRE engine wiki articles say a joint-venture or cooperation agreement was initially signed between Fiat and Peugeot Citroen in 1979 for the joint study of a brand new economical and ultra-modern engine.

    However the economic difficulties and financial setbacks during faced by the French manufacturer during at the beginning of the 1980s forced them to abandon the project before the start of the studies (not helped by the acquisition of Chrysler Europe), which led to Fiat deciding to study and produce the FIRE engine independently under the direction of engineer Rodolfo Bonetto. Peugeot Citroen in turn would develop the PSA TU from the older PSA-Renault X family aka “Suitcase” engine.

    Despite Peugeot Citroen’s earlier abandonment of the FIRE project, it would appear to have not stopped its pre-existing ties with Fiat if the latter did indeed contribute the 704cc Twin and 750cc 3-cylinder FIRE engines to the Citroen ECO 2000 project. That inevitably leads to the question of Fiat’s involvement and interest in the ECO 2000 project and its contribution towards its own projects ( X1/72 to X1/79) that led to the 1991 Fiat Cinquecento (as well as indirectly via the FSM Beskid to the 1992 Renault Twingo).

    1. The SL 10’s 750cc 35 hp 750cc 3-cylinder FIRE unit does also raise the question of whether the Fiat Panda was originally due to receive it in place of the 34 hp 769cc 4-cylinder FIRE, had PSA remained involved in the project it is easy to see how both it and Fiat viewed a 3-cylinder FIRE as a replacement for both the 500/126 and 2CV/Visa Twins.

  2. Good morning S.V. Like you, I was an avid reader of Car Magazine in the 1980s and vaguely recall the ECO 2000, but was unaware of the context in which it was developed and its influence on the AX.

    Your description of the dismal 1970s resonates very strongly with me, as does your characterisation of the growing sense of optimism and excitement about the possibilities for new technologies in the decade that followed. Looking forward to the next instalment.

  3. There is something anticipatory of the C4 coupe about the sloping roof and vertical tailgate with high-level lights, no?

  4. Interesting story. However, it assumes a certain knowledge from it’s readers. For instance, PRN lunules. Never heard of it and it takes some time to google it for understanding. Same with DLO, sounds like designer terminology to me, and I’m not a designer. A short explanation would have been easier.

    1. Hi Zacharias – good points both. Apologies for slipping into a bit of jargon, I will try to avoid that in the future.

    2. Hi Zacharias, Thanks for your comment and welcome to Driven To Write!

      Apologies for our tendencies to slip into jargon. DLO is indeed designer jargon: it stands for ‘Day-Light Opening’, in other words, the window arrangement on a vehicle.

  5. Good afternoon, all. I remember the Citroën Eco 2000 and Renault Vista. I was and still am very interested in light weight vehicles. Thanks for sharing it here.

    DRAS stands for: la Direction de la Recherche et des Affaires Scientifigues.

    1. You best me to it, Freerk. Mi was guessing something like ‘Department de Recherches Automobiles Specialiste’ or similar (my apologies for mangling the French language).

      I found out more about Mr Yu – he’s done some interesting stuff. One of the many unsung design talents.


    2. That should have read ‘You beat me to it, Freerk. I…’, etc. Further apologies for mangling the English language.

    3. Hi Freerk. Thanks for this. If I had a prize for knowing what DRAS stands for, I would be sending it to you. How did you know, by the way?

  6. Fantastic post, fantastic subject! Thanky you!

    Now, did the 2005 Mercedes Bionic concept copy the Citroën Eco 2000 or, as was
    claimed by MB at the time, the naturally aero- (or better: aqua-)dynamic shape of a guppy?

    1. It is a similar shape – perhaps this is one of the ‘correct’ forms that should be adopted. M-B certainly appear to have put the time in to researching it. We could learn more from the solutions adopted by nature – both in terms of form and construction.

  7. A wonderful post which has stirred many thoughts (too many, possibly).

    As a species, we definitely need another ‘Year 2000’ to aim for. I know we have 2050 set as a carbon-neutral target date, but that’s a bit drab and the year 3000 is too far off. We need to get a bit of our optimistic naivety back.

    One of the things that really stood out in the article was the weight of the car – half a tonne, or about the same as an early, original Mini. It can’t be right that current cars weigh four or five times as much. I’ll avoid an anti-EV rant, as I know it’s early days and batteries will get much smaller, lighter and more energy-dense.

    Surely there could be a place for a modern version of this and other, similar concepts, though. With modern materials and technology, it could be staggeringly efficient.

    Anyway, here’s Citroën’s promotional film about the ECO 2000 from 1984.

  8. Great article! In the 80s when the cars were streamlined and aerodynamic, concepts like these were the future to be. Where dit it change path and instead of aerodynamic forms, sculpted designs came along, to be followed by the forms we see today?

  9. Thank you S.V. Robinson for this article. I am already looking forward to the second part.

    Vehicles like the ECO 2000 show quite clearly what has gone wrong with consumer awareness in the last 30 years.
    Even the reinterpretation of the abbreviation “Eco” over time is a clear example. Of course, economic is also ecological. Thirty years ago, this equation was well known and understood. (Today, three and a half tonne electric vehicles are called ecological. Meanwhile it is very difficult to distinguish satire from reality).

    The ECO 2000 has everything you need, what it doesn’t have you don’t need – if you’re honest – and a vehicle of this type would have been perfectly adequate for 90% of all rides for the majority of drivers.

    But thanks to some apostles, we took the wrong exit back then. Which is why the majority of drivers today are on the road with tanks weighing several tonnes – equipped with 23 airbags and 42 electronic assistants so that they can safely surf the internet while driving.

    PSA can be accused of not having made more of the concept. The AX is, especially visually, a boring and very hesitant further development of the ECO 2000.

    1. We need to tax vehicles by weight. That’d concentrate a few minds.

    2. Taxing by weight would also be hard to cheat, other than by filling the tyres with helium.

  10. This car is remarkably consistent with the Citroën design language as it evolved from the trapezoidal Fiore era (Karin concept) through the Bertone era cars, and fits right in as a progression of the Visa (before they ruined it, IMO), the Gandini designed BX. It also leans intuitively toward the future XM (glazing). It’s amazing how robust the brand’s design DNA was, along with the passion for its sanctity, considering how many designers took a turn at the tiller during this era.

    A hydraulically controlled but not fully automatic transmission seems intriguing in this application if it would liberate more efficient packaging and adequate responsiveness, as opposed to a compromised, convoluted mechanical linkage.
    It is an interesting side note that a different solution that eventually entered production: the electro-mechanical dual clutch transmission, was invented by a French engineer (Adolphe Kégresse in 1939) for use in the Traction Avant (but it wasn’t used).

  11. I’ve been reading DTW for a while now, I was afraid that it was some insider site, but I’m glad you understand my comments. Apart from some missing knowledge on my side, I read it almost every day. And please don’t understand me wrong SV, this is a very interesting article about a car I didn’t know. I had a Citroën AX though, long ago.

    1. No offense taken and it very rarely is here, Zacharias. All are welcome and encouraged to view, read, comment and debate. There’s a core of regulars who contribute and comment, but it’s definitely a case of the more the merrier. Your comments are helpful to remind us all to keep the words straightforward and inclusive, and explain technical language/ jargon when it is used.

      I really liked my AX and loved the benefit derived from its low weight, willing engine and superb gearbox. Just a shame its styling inside and out was not more inspired.

    1. Ummm, no. It wasn’t one that either featured in my mind because it was post-eighties, nor caught in my memory for the epilogue. Sorry. Please do bring it in to future comments or by other means.

    2. There’s the rather interesting 2001 Opel Filo by Bertone, too.

  12. The global design isn’t terribly interesting to me, being dictated by the windtunnel, but it’s full of intricate detail. I like how the line for the window openings continues, how the roof line curves and how the rear side window is curved:

    It also has shades of the AR6 to me, but that’s probably because – as you mention – the design thinking was converging on similar themes (image AROnline).


  13. Funny you should mention the AR6, it will be making a guest appearance later in this series…

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