The Lotus Carlton (in mainland Europe, the Lotus Omega and sometimes called the Vauxhall Lotus Carlton in the UK) was an Opel Omega (Vauxhall Carlton) saloon upgraded by Lotus Cars to be a 177 mph (285 km/h) sports sedan with acceleration to equal contemporary supercars.
Like all Lotus vehicles, it was given a type designation — Type 104 in this case. The external differences were minimal with the addition of a rear spoiler, vents on the bonnet, Lotus badges on the front wings and bootlid, a bodykit and considerably wider wheel arches distinguishing it from a standard Carlton.
The car was only sold in one color, a shade of British racing green called Imperial Green, a very dark green that in anything but direct light appears black.
Source: Wikipedia, 2014