2007 Audi S6
An S6 gets set to lead a group of cars out onto Mosport International Raceway. Click image to enlarge

Article and photos by Chris Chase

Discuss this story in the forum at CarTalkCanada Bowmanville, Ontario – Audi says the latest members of its famous family of ‘S’-badged performance models – the S6 and S8 – stand for “unequivocal dynamism.” We’re not entirely sure what that means, but what we do know, having had an opportunity to drive both cars at Mosport International Raceway recently, is that these are the two fastest and fleetest big sedans that Audi has ever screwed together.

Not that we were surprised to learn this: Audi’s got a history of bolting sporty suspensions and big engines to its sleek sedans, turning comfortable cruisers into five-seat road rockets. The first S6, which was based on the Audi 100 and was originally badged S4, was powered by a turbocharged five-cylinder engine, with a 4.2-litre V8 offered as an option. That car was built from 1991 to 1997, and was replaced in 1998 by a redesigned S6, powered exclusively by that same V8, making 335 horsepower. The first S8 was introduced in 2001, and was powered by a 360-horsepower version of that ubiquitous 4.2-litre V8.

2007 Audi S6
Audi S6 V10 engine. Click image to enlarge

This latest pair of “S” models is notable for eschewing anything so pedestrian as an eight-cylinder – or even a 12-cylinder – engine, with Audi opting to use a 5.2-litre 10-cylinder engine derived from that used in the Lamborghini Gallardo. While 10-cylinder motors are novel, it’s not the first time one has been used in a sport sedan; BMW’s latest M5 uses one too. Audi’s 10-banger makes 435 horsepower in the S6 and 450 in the S8.

For Audi’s purposes, the company says a 10-cylinder engine is “the ideal design for realizing sporting aspirations.” The company talks about how a ten-cylinder has fewer moving parts than a 12-cylinder and smaller cylinder bores than an eight-cylinder of the same displacement, which Audi says helps reduce reciprocating mass and friction and makes for an engine more suited to high revs. And there are lots of those, considering this is not a small engine.

2007 Audi S8
The S8 uses a firmer version of the air suspension found in the standard A8. Click image to enlarge

The S6’s 435 horsepower peak comes at 6,800 rpm, while the S8’s 450 horses reach their stride at the motor’s 7,000 rpm redline; both engines reach their peak torque output between 3,000 and 4,000 rpm. Both cars use a six-speed automatic transmission, with the same sport-shift and manual-shift functions found on this gearbox in the A6 and A8. While we’d love to see either of these cars with a true manual transmission, we think the manu-matic feature is superfluous. Simply place the shifter in sport mode and let the car do its thing and it will hold gears longer for better responsiveness.

But let’s bypass the technical mumbo-jumbo and get straight to the tangible stuff. Between our turns behind the wheel of these two new powerhouses, we were hanging around in the pit area at Mosport – the perfect spot to enjoy the sound of the V10-powered cars ripping up the track’s straight. Not surprisingly, both cars sound a lot like the Gallardo, which, we can assure you, is a good thing.

2007 Audi S6
2007 Audi S6
2007 Audi S6. Click image to enlarge

Mosport was a good choice of venue for the introduction of the S6 and S8; this is a very challenging track for novice and experienced drivers alike and helped illustrate how nimble these cars are, considering neither is particularly compact. The S8 rides on a more aggressively-tuned version of the A8’s air suspension system, and the S6 uses a firmer version of the A6’s more conventional coil spring suspension. Helping in the agility department are large wheels – 19s on the S6 and 20s on the S8 – that don’t hurt the cars’ looks either. Despite the firmer suspensions, both cars still rode very comfortably, though Mosport’s smooth surface is hardly the ideal place to evaluate a suspension’s comfort quotient. We’ll wait until we get a chance to drive these cars on public roads to say how tractable they are in daily use. That said, the ultra-fast RS4 is plenty usable in traffic, so we have little doubt the S6 and S8 will prove similarly user-friendly.

2007 Audi S8
2007 Audi S8
2007 Audi S8 (top); and some good advice for a rainy day at Mosport. Click image to enlarge

We didn’t get a chance to do standing-start acceleration runs, but it’s safe to say that the cars are good for the straight-line acceleration numbers Audi claims for each: zero-to-100 km/h in 5.2 seconds for the S6 and 4.9 seconds for the S8. Both cars are electronically limited to a 250-km/h top speed, but it’s not a stretch to surmise that either could outrun that velocity handily once relieved of that digital governor. Our top speed on a partly damp Mosport circuit – heavy rain throughout the day meant the track never dried up completely – was a very conservative 140 km/h, at which the cars were stable and smooth.

Exterior add-ons are subtle: both the S6 and S8 get distinct front and rear bumpers and rear diffusers, an integrated trunklid spoiler and four exhaust tips. The S6 also gets different front fenders that are 14 mm wider than those on the A6. Naturally, there are S6/S8 badges on the front and rear, and “V10” badges on the front fenders of both cars.

Pricing for both cars starts at more than $100,000 – $101,900 for the S6 and $129,700 for the S8 – and both are offered with a number of equally pricey options. S8 extras include a $4,800 Premium package, adaptive cruise control for $2,900 and a $7,800 Bang & Olufsen sound system (which we got to sample, and we’d dare say it’s worth the money if you love your music) and a $6,400 full leather interior upgrade. Check every box on the option sheet and the bottom line balloons to more than $155,000 before taxes and freight charges.

2007 Audi SX
2007 Audi S8
Interiors of the Audi S6 (top) and S8. Click image to enlarge

For the S6, there’s a Technology Package worth $3,700 (which includes advanced key technology, voice recognition and a navigation system), a $1,600 Warm Weather package that throws in a solar sunroof (which will work in concert with the fan to help keep the car interior cool when parked in the sun) and power rear and manual side window sunshades. A parking assist system with rear-view camera is a $1,000 option and adaptive cruise control is another $2,700.

The interiors are typical Audi-austere, but fit-and-finish is impeccable. The seats, while providing more lateral support than those found in the A6 and A8, feel very comfortable, although, we’d need more time behind the wheel to say for sure. The high-performance variants get some different interior trim options, but the one thing we wish wasn’t there is the frustrating Multi Media Interface (MMI) system that’s used to control various functions ranging from climate control to navigation system to the radio.

No car with a six-figure price-tag is a reasonable financial proposition for the average driver, but these are no ordinary Audis. For those who can afford to consider a car in this price range, head over to your Audi dealer now: the S6 and S8 went on sale across Canada last month.

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