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A new generation Audi A8 range containing
the UK’s ‘cleanest’ luxury saloon is about to prove even more
emphatically that size and environmental consideration are far from
mutually exclusive. The new A8 2.8 FSI with 199g/km CO2
output is the highlight of the new 2008 Model Year A8 line-up, which
opens for order in late August priced from £49,995 OTR and benefits from
improvements to styling, equipment, ride and handling and refinement
across the board.
With 210PS and peak torque of 280Nm at
3,000rpm, the sophisticated FSI unit sweeps the front-wheel-driven A8
2.8 serenely from rest to 62mph in 8.0 seconds and on to a top speed of
147mph. More crucially for an increasing proportion of drivers, it also
makes possible a combined consumption figure of 34.0mpg and a
significant drop in CO2 output to 199g/km, enabling the A8 to
comprehensively undercut not only petrol hybrid rivals in the luxury
segment, but also all diesel alternatives.
The
new A8 also features new valvelift technology - first seen in
the A6 Saloon and Avant earlier this year, the new 2.8-litre V6
capitalises even more fully than existing A8 units on the
efficiency-boosting features for which the A8 is already renowned. Given
the freest rein possible by the lightweight aluminium Audi Space Frame (ASF)
body shell, and complemented by unique-in-class multitronic CVT
automatic transmission which in many cases actually improves fuel
economy compared with a manual, it can fully demonstrate the benefits of
its FSI direct petrol injection and new Audi valvelift technology.
FSI already enables exceptionally
precise metering of the fuel injected into the combustion chamber,
ensuring that there is minimal wastage during each cycle, but the
valvelift technology augments this by controlling valve opening far more
precisely than conventional systems, improving fuel economy by a further
10 per cent. Valve lift is variable between two levels through the use
of sliding cam units mounted on the intake camshaft. When strong
acceleration is required, an electronic control mechanism selects a cam
profile which opens the valve as fully as possible for optimum
‘breathing’. When throttle usage is more relaxed, the control mechanism
selects a lower profile, reducing the amount of fuel and air compressed.
FSI efficiency is an advantage offered
by the six, eight and ten cylinder petrol models in the 2008 Model Year
A8 range, and the 3.0-litre V6 TDI and unique-to-Audi 4.2-litre V8 TDI
models are no less technologically impressive with their
state-of-the-art common rail piezo direct fuel injection. |
