Vauxhall's sister company, Opel, built the one-off Eco-Speedster using a new 1.3-litre common rail diesel engine, the first engine produced under the GM-Fiat powertrain alliance.
During initial testing the 112bhp concept, which weighs just 660kg, reached 113mpg and 155mph. It also complies with Euro IV emissions rules.
Vauxhall managing director Kevin Wale said: 'The Eco-Speedster is the symbol of our comprehensive diesel offensive and demonstrates the engineering expertise of Vauxhall in powertrains, lightweight design and aerodynamics. By the end of 2003 we will present a number of new, state-of-the-art diesel engines, with a range of power outputs, low weight and moderate fuel consumption.' The car made its debut at this week's Paris Motor Show.