High-Pressure Hydraulics by Citro?n

Starting from the DS Prestige, Henri Chapron could install all what the customer wanted in board of his car. Above a special DS 21 Prestige 1971 for the french radio station RTL. This prestigious model is intended for Jean Ferniot, the star journalist of the station. He had a true travelling office, a rare vehicle at this age.



Only 500 DS Prestige were made, the last a long time after DS stopping, 1977 or 78.


The appearance of the CX was a very bad news for Henri Chapron. Indeed there was a Prestige model, a longer CX, but it was made at Citroën Aulnay sous Bois. Anyway, this new model will never have the prestigious image of the DS, too many plastic inside and maybe too low also.

CX Landaulet, one of the last Citroën created by Chapron in 1978. Chapron was the very last prestigious bodyworker in France. Citroën DS and SM allowed him to work 20 or 30 years after Franay, Saoutchik, Antem, Weymann, Letourneur et Marchand, Figoni-Falaschi... It was one of the greatest. The factory closed in 1985.

8 years after the autonomy record (1050 km, see #84), the speed record for the CX Diesel


Atmospheric CX Diesel




The turbo brings 45 HP to the 2500 Diesel Citroën and the consumption is still lower. Great end of career for this old model in 1987.

Every years in sixties-seventies, about one month before Paris Motorshow, Citroën presented his new range in exclusivity to automobile-medias only.
This exposition was at Pré-Catelan, an upper class restaurant of the "Bois de Boulogne" at Paris.


1965 - DS 21

1971 - GS Estate

Ami 6 estate, Ami 8 estate, GS saloon and many other models were presented for the first time at this restaurant.

Andre Lefebvre, spiritual son of Gabriel Voisin


Left, Gabriel Voisin, aviation pioneer in 1908.
Right, Andre Lefebvre, began his career at Voisin then, after working only 2 years at Renault, entered at Citroën in 1933 to design the Traction.
He created also TUB, 2CV and DS.

A drawing of Gabriel Voisin who saw car like plane without wings.
The gravity center must be in any case in front of aerodynamical pressure center. Easy to understand when you look at a plane that is landing. The gravity center must be also as low as possible.





In 1923, there is already something of the DS in the race car Voisin Laboratoire.

After a long interruption because of the quarantine, Citroën Hachette Collection 1/24 is going on. Last model n° 21 : GS saloon 1015 cm3, maybe for the 50 th anniversary.

Hachette is working with some antique doents of the constructor as you can see above.



GS saloon and estate, GSA estate were the only cars to have their rear bumper directly fastened to the trunk door of the vehicle. The loading of luggage was more easy. Hydropneumatic suspension with constant height was also an advantage, especially for the estate version.

My CX is gone for the break today. For me, it was too much work (and money) for repairing hydraulics in my small garage. Among the four cars shoted in winter 2006-2007 there is no more only one on the road today !

lpsg is absolute shit

Around flat four GS engines (air cooled boxer motors)



Ami Super

Take an Ami 8 and a GS, shake a lot and you get an Ami Super !
In 70s the constructor was become master for recycling old models as 2CV, Ami, DS.

With 2 cylinders and 67% power in more, no more problem for overtaking trucks seems to tell Citroën marketing.

Plateform of Ami Super was the reinforced frame of Ami 8 that was itself the reinforced frame of 2 CV. We were at the end of a development.

Even the caravan ! :thumbs up:

Oltcit or Axel



Y model was a Citroën project for replacing Ami 8. To bad, in 1974 Peugeot took the control of the company and imposed the base of his model 104 for this new car. It became the Citroën Visa, first Peugeot-Citroën. Project Y was sold to Romania and Oltcit appeared in 1981 pulled by a flat twin 2 CV type or a flat four GS type.

Above, Citroën Visa assembled on a Peugeot 104 base.
Below, Romanian Oltcit


Oltcit came back in France and in Western Europe in 1984 under the name Citroën Axel and available only with 1100 or 1300 GS engines.
Today a lot of people think it is the last true Citroën model.

MEP X27






MEP for Maurice-Emile Pezous the dynamical Citroën dealership owner from Albi (Tarn-France)
He realized a small monoplace around flat twin Panhard 24 for beginning (MEP X2) then with GS engine (MEP X27). This economical race car was meant for driving schools.

Motorbike BFG


Propulsed by a 1300 cm3 GSA

Rotary piston engine adventure (1964 - 1980)

Amazing cinematic and simplicity of the design hide a lot of funtioning problems : gas-tightness, consumption, pollution, weak torque at low regime... This engine needed a torque converter and a specific exhaust.
However, in 1970, a lot of technicians believed in this technology.

Maybe they have some beautiful models at Hachette Collection Citroën 1/24 but the magazine that is joined... X_X
How could they confuse the flat-four engine of the GS with the twin-rotor engine of the GS...birotor? We can see this kind of error even in specialized publications. Rotative engines are totally forgotten today and often we see some photos mixed with other CX or GS images. CX because it has the front axle of the GS birotor, GS because of the body. Really to bad !

Some photos of the prototype M35 (1970)

This kind of Ami8 coach is a real laboratory on wheels. Citroën wants to test in real conditions the last version of his single-rotor rotary engine. He expects 500 prototypes made at Heuliez that he will sell to selected customers who will be some voluntary tester-drivers. A revolutionary marketing practice !

At its appearance in January 70, the prototype is tested by magazines like any serie car.


Barely the dashboard of the Ami 8

The reinforced Ami 8 plateform. Citroën don't test only the rotary engine, but also hydraulics of the future GS (suspension spheres, brakes control, high-pressure pump...). Hydropneumatic suspension is adapted to the Ami 8 chassis. GS gearbox is also tested on this prototype.

Seats have already the form of SM seats.




The new mechanical is attentively observed

One restored copy is kept today by Citroën museum

One of 267 tester-drivers. 3 engines in 35000 km, he deserves a citroenist medal . In reality, only 267 cars were assembled and followed directly by Citroën Nanterre manufactory where single-rotor rotary engines were made.

Citroën presented GS Birotor at Frankfurt Motorshow in September 1973.
It is equiped of a new twin-rotor rotary engine Comotor 624 (Citroën-NSU) assembled transversaly.















Brakes and front axle will be kept for the CX

Compact bloc motor-gearbox of GS Birotor

A torque converter is assembled between engine and gearbox (3 speeds only). Traditional clutch with disc. We shall find again this mechanical on the CX CMatic two years later.

What engine for the future CX ?


For who ? For what ? Why ? (notice the "beautiful" post-combustion exhaust on the photo)
Car magazines are not tender with GS Birotor when they can try it in 1974.
What they tolerated on the prototype M35 single-rotor is not accepted on a serie car sold the price of a DS. Citroën put a torque converter on its model but performances are not those of a classic 2 liter saloon and the consumption ... It is a technical and commercial failure. GS Birotor is quickly left in full first oil crash in 1975. But rotary engine searchs are going on and encouraged by the new owner of the firm Peugeot.



As of 1972 the style of the future CX is nearly fixed. 4 motors are expected :
- the old 2 liter of the DS
- 2.4 liter injection of the DS too
- a new Diesel 2.5 liter
- a twin-rotor rotary engine from GS birotor for upperclass. Bigger and with injection, this motor is not still ready when it's time to commercialize the new model in 1974.


In 1979 a modern 2 liter Renault is replacing the old one derived from the DS. CX downscale is modernized this way and, next year, searchs about rotary engine are definitly left. All the efforts are put on the Diesel engine.

Some other cars with rotary engine


Mercedes C111 : Presented at Geneve motorshow in 1970, the powerful central rotary engine is working with 3 rotors then 4. The german constructor left quickly searchs about this technology.


NSU Spider is the first car commercialized with rotary engine single rotor in 1963 (licence Wankel). With its motor assembled at the rear, the Spider is derived from the small coach Prinz in photo above.

NSU RO 80 : this modern saloon appeared in 1967 is a front wheels drive pulled by a twin-rotor rotary engine Comotor 624, a jointventure Citroën-NSU with a manufactory in Sarre at Alfortweiller. Both constructors plunged barely at the same time.

Mazda, champion of the rotary engine



In 1978 seven models of the range Mazda are available with a rotary engine. Customers have the choice between both technologies. At the opposite of Citroën-NSU, Mazda cars don't need torque converter or post-combustion exhaust. It's working fine without these devices. Only the consumption remains a problem. Most of the drivers prefer traditional engines and Mazda will keep only the coach RX7 propulsed by a rotary engine.

Winner of the "24 heures du Mans" 1991 with the 787B, Mazda proves the endurance of his rotary engines.



Mazda RX2 1971


Mazda RX7 1980 (the profil of a Porsche 924)




Mazda RX7 1991. All the Mazda with rotary engine are some rear propulsions

Mazda RX7 1993

2 restored DS19 model 1957, colour : champagne - aubergine (roof)
The first seen at the historic race 1000 Miglia 2020, second made the cover of the magazine "Rétroviseur" in december 1988. Nearly the same !


Only interior seems different