An Audi limo

It is clear that Audi is on an aggressive drive to match and then beat luxury stalwarts Mercedes-Benz and BMW at their own game. And in many segments, it seems to be already giving its two German rivals a run for their money.

The exception lies in the limousine segment. Audi's flagship A8, for all its lightweight and innovative construction, has not won over the towkays swayed by the Merc S-class and BMW 7-series.

But things may change with the new A8. In view of growing environmental awareness (or sheer power hunger), Audi will for the first time include diesel-powered models in its A8 line-up here.

Its 4.2-litre V8 turbodiesel has 350bhp and a massive 800Nm of torque. This allows it to outsprint the more powerful 372bhp 4.2-litre FSI petrol model to 100kmh. It clocks 5.5 seconds, versus the FSI's 5.7 seconds.

Both reach an electronically governed top speed of 250kmh but the 4.2 turbodiesel will be far more miserly on fuel, consuming just 10.2 litres for every 100km in the city, compared with 13.3 litres for its petrol sibling.

Audi also offers a 3.0-litre TDI with just 250bhp but a respectable 550Nm of torque. This model is even more economical, sipping 6.6 litres of diesel for every 100km in the city.

Two more engines will be added a little later: a 260bhp 3.2-litre V6 FSI and a very frugal 3-litre TDI rated at 6 litres every 100km.

As expected of a flagship, the new A8 is literally packed to the gills with a raft of the latest electronic bells and whistles. The front headlights are completely LED-powered, with GPS-guided 'predictive lighting'. It even compensates for an oncoming vehicle by dipping more as the car closes in to reduce glare, while keeping the beam on the kerbside as high as possible.

Another innovative feature is MMI Touch, which is Audi's Multi Media Interface with a touch pad. The driver can write his destination on the pad and the navigation will do the rest.

Amazingly, the system recognises handwriting as bad as a doctor's. It will even decipher Chinese characters for the China market.

Audi joins the hi-fi war with a B&O sound system (an option) that pushes out 1,400 watts through 19 speakers. Even the standard issue 600-watt Bose system sounds good and will interface with your iPhone via the dedicated hardwire connector or Bluetooth.

If we were to list all the A8's innovative gadgets, there would not be space left for the drive impression, which is as follows:

The 4.2 V8 FSI delivers expected performance with a definite sporty inclination and exhaust note. Its throttle response is sharp and would be my first choice had I not tried the 4.2 V8 TDI. While the noise this turbodiesel makes cannot compare with the sporty aria from the FSI, it pulls away more effortlessly than a petrol car.

The shove you feel as you hit the accelerator pedal is astounding. The car has enough torque to overcome the full-time quattro system. In fact, traction control and stability control intervene occasionally to keep the car in check.