ADVANCED technology specialists are claiming to have paved the way for General Motors to put a remarkable new super-economy family car into production. Capable of operating at an astonishing 94mpg, the five-seater could be on sale in four years' time.

Similar in size to the Vauxhall Vectra, the car is likely to be based on a hybrid concept model launched by General Motors at the North American International Auto Show in Detroit. Powered by a 1.3-litre, turbo-charged three-cylinder Isuzu diesel engine backed up with electric motors, the Precept four-wheel-drive 'technology demonstration' show car has already achieved the equivalent of Europe's so-called 'three-litre' economy threshold by covering the equivalent of 80 petrol miles on the smaller US gallon in test sessions or 90 diesel miles.

'The numbers are looking good and are very encouraging. We've even taken the car through the 100mpg barrier in steady-speed trials,' project director Dr Ron York told Fleet NewsNet at the corporation's Advanced Technology Vehicles headquarters in Troy, Michigan. During the next few weeks, the concept for a spacious upper-medium saloon should win certification as the first car to reach the 80mpg target set by a research programme shared by GM, Ford and DaimlerChrysler and US Government laboratories.