BTR

POWER: 374hp

Its acronym standing for Gruppe B Turbo Ruf, the BTR was based on the G-series Porsche models, albeit with a 3.4-litre, turbocharged flat six hiding under a large, fixed rear wing. Available in either narrow- or wide-body form, the later BTR

III of 1988 to 1989 was the first single-turbo engine to be fitted with Motronic engine management, again beating Porsche to the development.