Two hundred and thrirty-two horsepower doesn't sound all that impressive when tasked with hauling something the size of an Audi A8 around. Let's face it, some hot hatches pack more power than this. There are, however, horses and horses. Lead this horse to water and it'll start drinking from a black pump. This sort of power from a diesel engine spells monster torque and some serious shove in the back. Couple that with the sort of fuel economy you'd expect from a shopping hatch and the Audi A8 3.0 TDI represents quite a package.

At its original launch, Audi billed this car as the world's first large luxury diesel saloon to meet emissions regulations, lauding its superior cleanliness over rivals from BMW and Mercedes. Mind you, don't be lulled into thinking Audi are simply content to rule the roost at this end of the diesel sector. They have bigger aspirations for the A8 3.0TDI, namely tilting at the best petrol powered cars in the class. Peruse the statistics and you have to contend they have a point.

Fuel economy and carbon dioxide emissions we can take as a given. A diesel is virtually always going to walk all over its petrol equivalent in these regards but performance? That's a whole different ball game, yet the A8 will accelerate to 60mph in 7.6 seconds and on to a top speed of 151mph. Contrast that with the Mercedes S280 (9.5 seconds/144mph), the BMW 730i (7.9s/145mph) and the Jaguar XJ6 (7.9s/145mph). To be fair to these cars, they can all be found for considerably less than the Audi's £50,995 asking price but it does drive the point home. Diesel is no longer the poor relation. Drive the cars back to back and you'd swear the performance differential was even greater. That's because the BMW, which generates the most torque of these three rival offerings at 300Nm, is utterly trounced by the 450Nm of muscle available under the Audi driver's right foot. This translates into effortless overtaking ability and a relaxed gait. You get a hint as to how little you need to stretch the engine to get results when you realise that peak torque is attained with the rev counter barely above tickover at just 1,400rpm.

"One danger for Audi is that the A8 3.0 TDI suddenly makes the 3.2-litre petrol models look utterly superfluous"

This sort of performance really puts the fuel economy figures in the shade, but they're worth reiterating. On the combined cycle, this A8 will manage 33.6mpg per gallon of diesel, the massive fuel tank meaning that you may only have to fill up once every 665 miles! Emitting just 226g/km of carbon dioxide, the big Audi won't slaughter those who choose one as company transport, the EuroIV compliant engine neatly sidestepping the three per cent benefit in kind taxation surcharge. One danger for Audi is that the A8 3.0 TDI suddenly makes the 3.2-litre petrol models look utterly superfluous.

Boasting a maximum five-star rating for security by the insurance industry's Thatcham Research Centre, it's reassuring to know that it's unlikely your A8 will go walkies in the night. It is, after all a very covetable good. Just take a look at the depth of thought that has gone into the design of the interior. Heeding the flak BMW took when they introduced their iDrive interface into the 7 Series, Audi responded by offering a simpler, more intuitive control system. Like iDrive, MMI features a rotary knob that marshals a bunch of functions indicated on the dash-mounted LCD display. Unlike the BMW system, it doesn't throw too much information at you too quickly. Whereas it's possible to change the rear damper settings on a 7 Series when all you wanted to do was blip up a little more air con, the Audi system feels altogether less threatening.

The 3.0 TDI spearheads a recently improved A8 range. The current model benefits from a smarter design for the trademark single frame grille, LED indicator strips in the side mirrors and LED tail lights. With this variant, there's a choice of SE or Sport trim, plus short or long wheelbase bodyshapes. Mechanical improvements to the latest A8 range include a re-engineering of the rack-and pinion speed-dependent steering to permit a more direct feel, and revision of the dampers, supports and general settings of the adaptive air suspension designed to give the A8 even tighter body control through corners and an even more unruffled ride. In conjunction with these measures, supplementary insulation using innovative new materials has also been added throughout the car, the result being that the A8 now records the lowest rolling, road and ambient noise levels in its class.

Like all A8 models, this one also benefits from specification enhancements. The 9-speaker, 230-watt sound system with six-CD changer is also now complemented by a DAB digital radio module for reception of ultra-clear digital broadcasts from an expanded choice of stations. Climate control is upgraded to a more sophisticated four-zone system with individual temperature and air distribution controls not only for front seat passengers but also for each of those in the rear. A8s also now benefit from heated front seats and Bluetooth mobile phone connection.

Like the Mercedes S-Class, this Audi adopts a full air suspension set up with four different set ups to suit differing needs. The A8 feels lighter on its feet than the previous generation version but ride quality has improved. This was the one big complaint with the MK1 A8, namely that the handling was good but you had to pay for it with significant bump and thump from the suspension. The power steering has been retuned to offer more feel, but it reverts to a fingertip lightness at parking speeds. It's still probably the only weak point in the A8 makeup.

It's not often that somebody steals a march on the likes of BMW and Mercedes but at this precise moment, there's clear blue sky between the best that Munich and Stuttgart are producing and the Audi A8 diesel models. The 3.0-litre TDI version only adds to Ingolstadt's superiority in this regard and will be a hard act to better - unless, of course, to opt for the 4.2-litre TDI engine with its mind-boggling 650Nm of torque. It's time to realign your sights if you want to take aim on the state of the luxury car art.

TOP 4 AUDI DEALS

The results below show the top AUDI deals on buyacar

	Audi A8 3.0 TDI Quattro SE 4dr Tip Auto Saloon
	ETR	Mthly £843	Saving £6,698	Price £44,302
	Audi A8 3.0 TDI Quattro SE LWB 4dr Tip Auto Saloon
	ETR	Mthly £896	Saving £7,170	Price £47,390
	Audi A8 3.0 TDI Quattro Sport 4dr Tip Auto Saloon
	ETR	Mthly £897	Saving £7,139	Price £47,011
	Audi A8 3.0 TDI Quattro Sport LWB 4dr Tip Auto Saloon
	ETR	Mthly £950	Saving £7,611	Price £50,099

typical 9.52% APR

PCP finance quote over 48 months,  10,000 miles pa,  deposit of £1000