It is common to hear the iconic expression citroën… créative technologie, which evokes a fun and memorable image, although it has become the subject of memes. However, upon visiting the Brazilian Citroën website, one observes a portfolio composed of three vehicles: the C3, a compact with mini-SUV characteristics and one of the most affordable cars in Brazil (close to R$ 80,000); the Basalt, which resembles a well-executed Fiat Fastback; and the Aircross, a wider and more functional version of the Basalt. Although these models are competent, they do not reflect the bold and peculiar nature of Citroën of the past.
In the past, owning a Citroën was an act of declaration, indicating that the owner was aware of the complex maintenance and possible chronic problems, but was willing to accept this due to the beauty or driving quality of the vehicle. In Europe, the situation is similar, despite the presence of curious items such as the electric minicar Ami, the C4 X sedan with raised suspension, and the persistent Berlingo. None of these vehicles compares to the Citroën that produced the remarkable C6, often seen as the last truly eccentric model from the brand.
When analyzing the timeline of Citroën, the disparity becomes clearer: the older the model, the stranger, more charming, and more innovative it proves to be. The evolution of the C6 shows its predecessors, such as the elegant XM, known for its angular lines and computer-controlled Hydractive suspension. The XM, in turn, succeeded the CX, famous for its extreme aerodynamics and concave rear window. The CX replaced the legendary DS, which revolutionized the industry with its floating hydropneumatic suspension and directional headlights. Before the DS, there was the Traction Avant, which, in the 1930s, challenged common sense by offering a luxury car with front-wheel drive.
The DS ended up attracting more attention, sharing the focus on innovation with the 2CV, the model most remembered for its contributions. While the DS represented high technology, the 2CV used innovation to promote practicality and low cost, helping France establish itself in the post-war period. All this serves to remind us that the past Citroën was indeed a creative technology manufacturer. Besides successful cars, there were unsuccessful experiments, one of the most interesting being the launch of the Citroën GS Birotor in 1973, in France, when the French opted to replace reciprocating pistons with a more triangular design.
This article addresses the Wankel engine, whose smooth operation (due to the absence of reciprocating motion), high specific power, and shrill roar are appreciated characteristics. Mazda was the only manufacturer to successfully invest in Felix Wankel's invention, using the engine in legendary lines such as the RX-7 and winning the 24 Hours of Le Mans with the 787B. However, other attempts were not as successful. NSU, the precursor to modern Audi, launched the NSU Ro 80, a luxury sedan that became a reliability problem due to premature wear of the rotor seals, leading to the company's bankruptcy.
The fiasco of the Ro 80 affected NSU's reputation, but the German brand joined forces with Citroën in a joint venture called Comotor in the late 1960s to produce rotary engines on a large scale. It was from this collaboration that the Citroën GS Birotor emerged. The Citroën GS, launched in 1970, occupied the intermediate position in the brand's range, situated between the economical 2CV (and the Dyane) and the luxurious SM. Classified as a small family car in Europe, it offered the appearance of a more expensive and faster car, thanks to its long hood, fastback silhouette with a large glazed area, and partially covered fenders.
The GS marked Citroën's entry into the volume segment, aiming to meet the growing European middle class, as the brand only offered very basic or extremely sophisticated options. The goal was to compete with successful models of the time, such as the Renault 12, Peugeot 304, Simca 1100, and Fiat 128. To persuade consumers to switch from more traditional and cheaper rivals, Citroën implemented the strategy of democratizing luxury, equipping the GS with hydropneumatic suspension, four-wheel disc brakes, and exemplary aerodynamics, such as the Kamm tail, providing the comfort of a DS or CX for a fraction of the price.
Even in the simplest versions, the mechanics were unusual: the front engine was an air-cooled flat-four, with a displacement between 1.0 and 1.3 liters and power between 54 hp and 66 hp, capable of being coupled with four-speed manual or three-speed semi-automatic transmissions with hydraulic clutch actuation.
Presented at the 1970 Paris Motor Show, the GS received acclaim from the press and the public, winning the European Car of the Year award in 1971. Commercially, it was an immediate success, leaving Rennes in over 20,000 units monthly and becoming Citroën's best-selling car of its time. Combining the original GS and the GSA hatchback, the model exceeded 2.45 million units between 1970 and 1986, making it the second best-selling model of the brand, behind only the 2CV.
With the success of the GS, Citroën saw it as an ideal laboratory for its most ambitious experiment. The partnership with NSU, established in 1967, allowed for the mass production of the rotary engine used in the experimental M35, a compact with hydropneumatic suspension and a small rotary engine. 267 units were built between 1969 and 1971 for testing. For NSU, the agreement was an attempt to recover losses after the NSU Ro80, which survived until being integrated into Volkswagen in 1977.
The M35 program was short-lived due to reliability issues and excessive fuel consumption, as well as rotor seal wear. However, realizing that the GS would benefit from a more powerful engine, Citroën decided to implement the Wankel. The result was the GS Birotor in 1973, an evolution of the M35 with the addition of a second rotor, increasing the displacement to 995 cm³. Although it was the smallest in the line, it was the most powerful, with a dual-body Solex carburetor and 106 hp, available only with the three-speed semi-automatic transmission.
Visually, the difference between the GS Birotor and the standard GS was subtle but structural. The fenders were widened to support wider wheels and tires, the floor was modified to accommodate the new mechanical assembly, and the brakes were mounted on the wheel hubs (unlike other GS models, where they were internal). The interior also featured superior finishing, aligned with the premium proposal of the Birotor. Citroën's intention was not to sell large volumes, but rather to affirm the brand's commitment to innovation and luxury, charging a price 70% higher than the standard GS, approaching that of the DS.
Additionally, the French tax authority imposed a fiscal burden. The annual tax was based on 'puissance fiscale' (fiscal horsepower), which favored low-displacement engines. Despite the modest 995 cm³, the legislation applied a punitive multiplier to Wankel engines, classifying the car in the 11 CV bracket, the same category as two-liter sedans like the Peugeot 504 and the DS, causing the owner to pay executive car taxes even before starting it.
