The Turbo Esprit came with the Citroen C-35 transmission. As with many of the parts on the pre-GM cars the transmission is a little rare. If you have problems or issues, you might attempt to contact Harry Martens at http://www.ds-vitesse.com/home_uk.html
Quaife makes a limited slip differential for the later model Esprits with the Renault UN-1 transmission,PN# QDF5M?
Also, Quaife makes LSD for the C-35 Citroen transmission, QDF13H?
. In USA and Canada these LSDs?
are available from IMSservice