Renault presented the Vesta project at the end of September 1982. The name stood for Véhicule économe de systèmes technologie avancés, later rendered informally by Deutsche Renault AG as an experimental vehicle for energy saving through new technologies and components. The Vesta was a small three-door, four-seat research car aimed at proving that a vehicle could carry four people and their luggage at an average consumption of 3 litres per 100 km, while matching the performance, comfort and safety level of a standard 1982 small car. Its design was also meant to allow potential large-scale production from 1990 onward.
The underlying project had begun in early 1981, half-funded by the French Ministry of Industry, focusing initially on engine efficiency, drivetrain friction losses and aerodynamic bodywork research. This led to the choice of a front-wheel-drive layout with a transverse engine. A one-box body shape was considered but rejected, since it failed to bring a significant aerodynamic improvement and posed greater difficulties, including engine bay accessibility and added weight.
The scale model shown in autumn 1982 achieved a drag coefficient of 0.22 without cooling airflow, with a running vehicle expected to reach around cw 0.25. The car measured 320 cm in length and just 152 cm in width, with a target weight of 520 kg. Projected consumption figures were 2.28 l/100 km at 90 km/h, 3.64 l/100 km at 120 km/h, and 3.05 l/100 km in an urban cycle, giving an intended average of around 2.99 to 3.0 l/100 km.
The running prototype revealed in autumn 1983 used a steel body structure combined with plastic components to save weight: polyurethane foam reinforced with fibreglass for the roof and door trim, polymethacrylate for the tailgate, and polypropylene for the bumpers and wheel arches. The rear axle used a simple torsion tube with trailing arms, the front wheel carriers were forged aluminium, and the light-alloy wheels measured just 11 inches in diameter.
Power came from a purpose-built 716 cc three-cylinder engine mounted at an angle behind a grille resembling that of the second-generation Renault 5 launched in September 1984. It produced 32.5 hp at 4250 rpm and 60 Nm of torque at 2500 rpm, with electronic integral ignition using two spark plugs per cylinder. Notable features included an overhead camshaft with torsion-bar-type valve actuation, Heron combustion chambers for lean burning, a multi-part crankshaft with two main bearings, needle bearings on main and connecting-rod bearings, and elongated connecting rods, all aimed at reducing friction. Drive went through a five-speed gearbox with an aluminium casing and long gear ratios. Since the powertrain remained under development, Renault did not release performance figures for this first running prototype. Dimensions included a wheelbase of 222.5 cm, track widths of 126/119 cm, overall length/width of 327/152 cm, and a weight of 510 kg.
