Citroën BX

The BX achieved a very low kerb weight, thanks to the innovative and widespread use of plastic body panels (shown in yellow below) which comprised 11% of the unladen weight. The bonnet was made of a colour-impregnated composite called SMC. The tailagate was made from a similarly coloured composite called ZMC. The bumpers were made of polypropylene EPDM which was colour impregnated and formed using injection moulding.
The elements shown in green were galvanised steel which resulted in an extremely durable and rust free vehicle for its era.

Despite its angular appearance, the BX was surprisingly aerodynamic - the CD of the base model achieving a very respectable 0,34 while the CDS was 0,63. 

Like other hydropneumatically sprung Citroëns, this figure represents a real world achievement since the angle of attack remains constant, irrespective of load, acceleration, deceleration or speed.

Couple this good aerodynamic performance with low body weight and one has a recipe for good performance coupled with good economy.

Thanks to the introduction of ABS braking, the BX driver could maintain control under heavy braking in the most adverse conditions.