The GS was Citroën’s mid-range model developed to fill the gap between the luxurious DS flagship and the smaller economy models like the 2CV and Ami. With its impressive list of specs including hydropneumatic suspension, all-round disc brakes, great aerodynamics and so on, the GS, launched in 1970, soon gained popularity. Seeing that the car was getting good reviews for its handling characteristics and ride quality, Citroën decided to drop the Wankel rotary engine into its engine bay, leading to a new variant, the GS Birotor, being launched in 1973.

Citröen, which was a co-investor with German brand NSU in rotary engine maker Comotor, had been long contemplating adopting the technology into its cars. However, NSU’s Ro80 was a commercial failure leading to the company being absorbed by the Volkswagen group. Moreover, the bad reputation for reliability that the Ro80’s engine had gained made potential customers wary of the GS Birotor, as its engine was almost identical to that of the German car. It also didn’t help that Citroën had to increase the price of this model due to the fact that rotary engines were relatively new technology then. Thus, the GS Birotor was almost as expensive as the far superior DS, and nearly 70 per cent costlier than any other GS model.

To make things worse for the French carmaker, the oil crisis that drove fuel prices sky-high happened a few months after the car was launched, and since fuel economy was not one of the rotary engine’s strengths, sales got hit even more. After nearly two years of miserable life, the GS Birotor was scrapped in 1975 and Citroën got its dealers to buy back most of the 800-odd units sold so that they could be destroyed.

It also abandoned the plan to use a rotary engine to power the forthcoming CX model. It’s a shame that the GS Birotor didn’t work for Citroën, because but for the poor fuel economy and the unfortunate legacy from NSU’s failure, it was a decent car.