(Vauxhall press release)
VAUXHALL'S G90 CONCEPT CAR: FRUGAL, EFFICIENT AND FUN

• Frugal: CO₂ emissions of only 90g/km
• Light: four-seater weighs only 750kg
• Aerodynamic: teardrop shape (cd = 0.22)
• Lively: 3-cylinder ECOTEC engine with 112 mph max speed

The G90 concept car is Vauxhall's realistic vision of an innovative, minimal-consumption family car of the future.

A spacious four-seater in the Astra class, the G90�s 60PS, three-cylinder petrol engine produces low CO₂ emissions of only 90g/km (hence its name), easily undercutting future limits proposed by the European Union. Innovative weight-saving for a low 750kg kerb weight with a drag coefficient of only 0.22 make the car extremely frugal with fuel consumption of over 72mpg.

G90�s power plant was chosen 'off the shelf' from Vauxhall�s current range of ECOTEC engines and the Corsa�s advanced, efficient and lightweight three-cylinder, 1.0-litre 12v unit proved the perfect choice. It offers 60PS and maximum torque of 85Nm at 2,800rpm and reaches the impressive top speed of 112mph.

Aerodynamic: perfect shape (cd=0.22)
G90�s high top speed is a result of its excellent drag coefficient (0.22) and a frontal-area index (cd x A) of only 0.45. The fundamental concept for the car was a striking teardrop shape with a sloping roof and sharply cropped tail, which may point the way to Vauxhall�s future styling intentions.

The greatest aerodynamic advances are in G90�s underbody area and were obtained by allowing the floor to rise at the rear by an angle of six degrees. This results in a �diffuser effect�, well known from racing car design. Together, the rearward sloping roofline and the low trailing edge on the tailgate combine to reduce the rear surface area, allowing airflow above and below the car to pass the body faster, resulting in less turbulence and reduced drag.

Aerodynamic detailing is easy to see at many points on the body -- the partly concealed rear wheels, the smooth side panels or the two aerodynamic humps in the roof that guarantee excellent headroom for all four occupants, while the recess between the domes helped reduce the total frontal area.

A distinct feature of the 1650-mm-wide, 1477-mm-high car is the wind tunnel influenced teardrop-shape at the rear. To ensure the G90 kept as close as possible to this pure, natural shape with a narrow tail section, its rear-end dimensions were reduced so the rear tread (1360mm) is narrower than the front (1452 mm).

Lightweight construction
G90�s low weight comes from the strategic use of lightweight materials like aluminium and magnesium. Its low fuel consumption means a lightweight fuel tank with a capacity of less than seven gallons is enough for a range of nearly 500 miles.

Lighter brakes are also possible, while there are weight reductions on all chassis components, and the stainless steel exhaust system weighs only 13.1 kg, almost six kgs less than a comparable conventional system.

G90�s chassis has a lightweight torsion-beam rear suspension that�s so compact that the strut turrets no longer protrude into the luggage compartment, for a more generous load-width.

The large 17-inch alloy wheels with low rolling-resistance tyres are another feature. Their tread design is such that the tyre�s contact-patch area is relatively small, but increases significantly when braking or cornering for a combination of low fuel consumption and high safety.

Nick Reilly, Vauxhall�s chairman and managing director says: "The G90 incorporates well-known Vauxhall characteristics such as excellent aerodynamics, attractive design and good fuel economy. And it highlights the responsibility we bear as a car manufacturer for the environment and for future generations."