Audi S6 and S8 V10 2006 Review

What we liked
>> Strong mid-range torque
>> Vast interior space
>> Relative value in face of mega-$$$ competition

Not so much
>> Expensive DVD option
>> Lack of punch off the line in S8
>> Dynamic mode ride in S8 is a bit jittery

OVERVIEW
When it comes to German prestige brands, BMW has long had the image monopoly on sporty sedans via its powerful high-end inline six-cylinder and V8 cars and M Division products. But in recent years Mercedes-Benz has upped the ante with its broader range of AMG-modified products and even Audi has been getting in on the act with S and RS model variants of its mainstream line-up.

For the latter, it now has two new medium and large sedans that aim to offer a serious sporting drive and performance in a subtle, stylish and practical package.

The S6 is the range-topping sports variant of the A6, while the S8 is the second rung entrant in the A8 sedan range. At the heart of both cars is a new powerplant that is a development of the 5.0-litre V10 found in sister-company Lamborghini's Gallardo sportscar.

As you would expect of Audi performance cars, they both feature the company's trademark quattro all-wheel drive drivetrain with the engine mated to a six-speed tiptronic automatic transmission.

PRICE AND EQUIPMENT
Being based on the A6, the S6 is the lesser priced of the two performance sedans with prices starting at $195,900 -- a $50,000 premium over the previous range-topping A6, the 246kW/420Nm 4.2-litre V8 quattro.

The larger S8 is stickered for the showroom at $259,900 (an increase of $41,800 over the long wheelbase 4.2-litre V8 A8) with only the $326,000 6.0-litre W12 LWB A8 sitting above it.

As big, luxury and expensive cars, there is no shortage of equipment with the S6 running with a long list of standard kit.

Visual clues that mark the S6 include wide 19-inch alloy wheels shod with 265/35 rubber sitting within flared wheel arches, a subtle boot lid spoiler and at the front, a line of LED daytime running lights sitting below the Xenon headlights.

Inside, trim details in carbon-fibre and alloy highlight the sporty nature of the S6, as do the bespoke big bolstered but comfortable leather trimmed and heated front power adjustable seats.

The windows, heated folding mirrors, rear sunblind and sunroof are all power operated, and climate control, cruise control, front and rear parking sensors, bluetooth connectivity, satnav, television, voice control for nav/audio/phone, front and rear fog lights, automatic windscreen wipers and headlights and an excellent 13-speaker BOSE six-stack CD audio system are all included.

Apart from being obviously bigger, the S8 also gains on the equipment front. Its LED running lights are integrated into the headlight cluster (which also contains adaptive xenon headlights) while it sits on wider 20-inch alloys with 265/35 tyres.

It also gets more leather, double-glazed windows, phone and a monster 1000w 14-speaker six-stack Bang & Olufsen audio system. Surprisingly, however, even after parting with over a quarter of a million dollars, the rear seat DVD entertainment system is a $12,000 option!

Derived from Lamborghini's Gallardo powerplant, the engine gets a slight capacity increase (to 5.2-litres) and feature's Audi's FSI direct-injection technology that allows a relatively high compression ratio of 12.5:1.

The all-alloy engine is fitted with variable valve timing for its 40 valves and in the S6, generates maximum outputs of 320kW at 6800rpm and 540Nm between 3000rpm and 4000rpm. Audi claims a 0-100km/h sprint time of just 5.2sec.

In the S8, a retune of the same base engine produces 331kW at 7000rpm and 540Nm at 3500rpm enabling the bigger and (at 1940kg) 30kg heavier car to shave 0.1sec off the S6's 0-100km/h time.

Both cars use the same six-speed automatic transmission with steering column mounted paddles for the manual shifting mode.

The cars' quattro drivetrains are biased slightly towards the rear with a 40/60 torque split under normal driving conditions.

As you would assume, both cars also share a sports suspension with the S6 using a firmer version of the A6's optional multilink front and rear steel-sprung sports suspension.

The S8 features the same adaptive air suspension as its A8 kin using the A8's sports setting as the default. It is, as in the A8, continuously adaptive to road and driving conditions and also offers four modes of operation (automatic, comfort, dynamic and lift) with damper rates and ride height -- from 95-125mm.

PACKAGING
Boarding on a large sedan in dimensions if not class, the S6 offers plenty of space inside front and rear. (To read about the A6 on which the S is based click

The front sports seats have been designed specifically for the S6 and feature bigger side bolsters to keep you firmly in place while remaining extremely comfortable and cosy. With a multitude of power adjustments, getting a good driving position is easy while in the rear, two adults will ride in comfort with more than enough space while even three across the 60/40-spilt bench is not too much of a squeeze.

There are plenty of cubbies and oddments holders and the long flat boot is very large for the class with a capacity of 546 litres.

Step up into the S8 and there is, obviously, even more space inside. This is particularly the case in the rear where, without having got out the tape measure, it feels almost on a par with the likes of the Benz S-Class, BMW 7 Series and even the acreage offered by local LWB Holdens and Fords.

The S8's front pews feel slightly broader and less shapely than those in the S6 but are still very much of the sports variety with large side bolsters and good support and comfort. The rear bench will easily take three across. That said as a car that is based on the A8 (To read about the A8 on which the S8 is based click

With the extra passenger room in the rear, the boot is also slightly smaller than the S6 with a 500-litre capacity.

SAFETY
In both models, safety starts with the extremely effective and signature Audi all-wheel drive quattro system. Add to that ESP with traction control, an electronic diff lock and ABS with brake assist and you have a very competent active safety package.

For occupant protection, the airbag count numbers eight with dual-stage front bags for driver and passenger, seat-mounted side bags front and rear, and side curtain airbags.

The S8 gains an extra element to its ESP system and active front head restraints.

While both cars feature more than capable brake packages, if you want to dig deep, the S8 offers the option of ceramic discs ($13,000 for the front or $20,000 for front and rear) for its oversize 380mm front and 356mm rear brakes.

COMPETITORS
As mentioned before, the German manufacturers have been growing their respective sports sedan offerings in Australia over recent years (for example, Australia over-achieves in terms of AMG and M sales) and the Audi V10 twins are up against some serious competition.

For the S6, first in the line of sight is BMW's M5 (which also sports a V10 -- a 373kW/520Nm 5.0-litre unit) which starts at about $230K. Likewise, Mercedes' 378kW/630Nm 6.3-litre V8-engined E 63 AMG hits the market at about the same price.

This means the Audi sports-sedan undercuts both by more than $30,000.

Another slightly lesser endowed rival might be Jaguar's $220K XJR that ‘only' uses a 298kW/553Nm supercharged 4.2-litre V8.

Loyal Aussies might like us to throw HSV's latest Grange into the mix here. Yet to be officially released, at 307kW it's well short on mumbo but there'll be six figures of 'change' and then some to spend to bridge the gap...

Rivals for the S8 are thinner on the ground. Although BMW doesn't offer an M version of its 7 Series, there is the 327kW/600Nm 6.0-litre V12 760 which will set you back close on $350K.

Mercedes does have an AMG version of its big S-class limo but with a 450kW/1000Nm 6.0-litre twin turbo V12 engine, sub 5-second 0-100kmh, and price tag of $450K, it is in another league altogether.

Until the S63 arrives in March 2007 (and expect a circa $290K pricetag), the closest Benz in price and spec to the S8 is the $253,900 285kW/530Nm 5.5-litre S500 that will still hit the ton in a claimed 5.2sec.

Alas, the numbers just don't seem to quite translate into the drive performance. While hardly sluggish, the S8 is not as quick from standstill as you might expect. Such are the characteristics of the engine that it does like to be revved and doesn't quite get into its stride until around 3000rpm.

Once there it will keep pulling right through to the top end ensuring rapid in-gear acceleration and effortless overtaking. Indeed, the engine is delightfully smooth and refined with a pleasantly sporty sound.

Mated to a slick and smooth-shifting responsive six-speed automatic transmission, it makes for a rapid cruiser.

Head off the smooth freeway and onto a tight country road, with the air suspension set to dynamic mode and the S8 sits flat and solid on the road enabling you to point and shoot with confidence.  Although it is not unwieldy, you do notice the size of this big car when pushing hard through tight corners.

The quattro drive system and big fat low profile tyres provide an abundance of grip ensuring the ESP rarely intervenes although in this sporty suspension mode, it can feel a little jittery over badly cut up corners.

Although the S6 lacks the Audi Space Frame body technology and weighs in just 30kg less, it feels more lively and responsive on a twisty tarmac than the big bus. This could just be a perception thing due to the smaller dimensions, but the steering also feels that little bit sharper with more feedback -- although neither car offers the sort of feel you get in BMW's M5.

With the same peak torque as the S8 arriving slightly lower in the rev band, the S6 also feels a bit stronger off the line than its bigger kin and the purely mechanical suspension does a superb job of keeping the car sitting flat and stable on the road.

After a fairly brief taste test in seriously wet and foggy conditions in NSW's Southern Highlands, we came away from both cars feeling they hit the mark.

These are sporty and powerful cruisers that are eminently capable when the road turns tight and twisty. But -- without testing back to back -- they arguably lack the balls-out edge of BMW's M5 or indeed the latest AMGs.