Marcello Gandini worked on the Citroën BX when Bertone were called in to develop the XB Projet which had started under Robert Opron during in the 1960s. When Citroën were taken over by Peugeot in 1976 the radical ideas of the past had to give way to technology and components that would be shared with Peugeots. The BX relied on Peugeot engines in place of flat-4 units from the GSA, and the macpherson strut chassis was jointly developed for the Peugeot 405, although the BX was given hydropneumatic suspension unlike the 405. Gandini had designed the 1979 Volvo Tundra and the 1979 Reliant FW11 and gave elements of these to the BX. Launched beneath the Eiffel Tower in 1982, the BX was available with 1360cc or 1580cc petrol engines, and then in 1985 the 1905cc GT model was offered; a 1769cc diesel was available from 1984 and then turbo diesels were fitted. Top of the range cars featured a translucent panel in the c-pillar until the 1986 revamp. Larger lights front and rear, a revised interior, and a grille in place of the front slit were some of the changes for the MkII BX from 1986. A Phase II restyle from 1989 gave smoked glass rear lamps and other trim changes. A 5-door estate car model was available from 1986, and in 1994 the BX was replaced by the Citroen Xantia.