The Audi S8 has always been a dark horse in the performance luxury car segment. With a low starting price of $280,610 plus on-roads, it was always much more affordable than the $393,000 list-priced Mercedes-Benz S63 AMG.
In addition to a sizeable price hike — a $49,890 increase — from $280,610 to $330,500 plus on-roads, the engine has received a massive performance gain.
Outputs from the turbocharged 4.0-litre V8 engine have increased from 382kW of power and 650Nm of torque to a staggering 445kW of power and 700Nm of torque (750Nm is available between 2500rpm and 5500rpm thanks to an overboost feature) and sends torque through an eight-speed automatic gearbox. In line with the power increase, fuel consumption has also gone up. The S8 Plus now consumes 10.2L/100km, up from 9.6L/100km.
The power increase now pushes the big limo into supercar territory with a 0-100km/h time of just 3.8 seconds. Not only does it blow the doors off the rear-wheel-drive Mercedes-Benz S63 AMG, it demolishes the $493,000 (plus on-roads) rear-wheel drive Mercedes-Benz S65 AMG L in the 0-100km/h dash. It beats both by 0.4 and 0.5 seconds respectively.
The key difference being that the S8 Plus uses a quattro all-wheel-drive system, as opposed to the rear-wheel-drive set-up common amongst its competitors (although all-wheel-drive variants of the S-Class and BMW's 7 Series are available in other markets).
Under the S8 Plus's bonnet is an impressive 4.0-litre twin-turbocharged V8 engine that uses Cylinder on Demand (CoD) technology and places its two turbochargers within the 'vee' to increase thermal efficiency. The CoD technology allows the vehicle to shut down cylinders 2, 3, 5 and 8 on demand to help the car use less fuel when the full gamut of torque isn't required.
Helping echo the V8's deep thrum is the standard fitment of a sports exhaust. Reducing noise within the cabin comes courtesy of an Active Noise Cancellation (ANC) system that works in unison with the Bose sound system to reduce road noise and unwanted vibrations within the cabin.
You'll be able to tell the S8 Plus aside from the 'standard' S8 courtesy of blacked-out exhaust tips, a high-gloss exterior package and carbon-fibre inserts in the front spoiler and rear diffuser. There are 21-inch matt titanium-look alloy wheels help complete the visual package.
Inside the cabin, the differences come thanks to Valcona leather seats with leather treatment on the dashboard and doors. The roof lining is finished in Alcantara, while red contrast stitching in the seats and red carbon-fibre dashboard highlights give it a further sporty appeal.
The cabin is a great place to be thanks to leather and Alcantara covering almost every surface. While the normal sound system is great, we tested a car with the optional ($14,500) Bang and Olufsen sound system. Featuring 19 speakers, the 1400W sound system comes with Digital Sound Processing and a 14-channel amplifier. The sound quality is absolutely exceptional and is essentially a cinematic experience within the cabin of a car.
There are a number of other options available — some of the highlights include matt paint for $14,000 (only available on S8 Plus), carbon-ceramic brakes (as fitted to our test car, $25,840), double window glazing ($2500) and night vision assistant ($5970).
We hit some of the windy country roads around Phillip Island to put the S8 Plus through its paces.
Immediately obvious was the exhaust and engine note. The sports exhaust gives the S8 Plus and incredibly deep thrum that sounds quite similar to the RS7 Performance. It transforms the car from a stately luxury car to a mean, Autobahn missile.
Throttle response is absolutely exceptional, as is the brake pedal feel from the giant carbon-ceramic brakes. They measure 420mm with eight-piston calipers at the front, while the rear set comes in at 370mm with four-piston calipers.
As the pace increased, so did the response from the steering rack. The dynamic steering is an electrically-assisted variable-ratio steering system that feels go-kart-like in the vehicle's Dynamic drive mode as the inputs required to turn a corner become shorter.
That means you can turn in gently to get the car to tip in and barrel through the corner.
In addition to the dynamic steering, the S8 Plus is fitted with a quattro sports differential that uses a mechanical torque vectoring system to split torque between the two rear wheels. This system allows the vehicle to avoid understeer and tuck its nose in while accelerating out of a corner.
This works perfectly with the slingshot-like performance of the twin-turbocharged V8 engine. When it hits its overboost feature, you are thrown back into your massage seats as the car moves toward licence-losing speeds.
The engine feels continuously relentless and unphased by any sort of outputs requested from it. Driving in the vehicle's Sport mode offers the best of on-tap performance and quick gear shifts.
Steering wheel-mounted paddleshifters can be used to shift gears, but we found it best to let the car do all the leg work.
On the ride and handling front, the S8 Plus offered surprising handling and ride over rough surfaces. The air suspension does work wonders in Comfort mode to soften the ride and err on the side of comfort.
When switched to Dynamic mode, things change immediately. The ride becomes firmer and the body sits dead flat. The composure from this 2065kg limousine is really impressive.
Away from the sweeping bends of country Victoria, the S8 Plus really showed its true colours. I hopped in the back seat for a casual ride back to the racetrack and found it to be quite entertaining.
In addition to a comfortable seating position, rear seat passengers have their own climate controls and can also take advantage of the optional rear seat entertainment package (as a $9900 option).
This is a remarkable performance luxury car that couldn't put a foot wrong. It's incredibly fast in a straight line and just as impressive when shown a set of corners.
It's a big performance step up from the 'regular' S8, but comes with a host of extra features and incredible performance to boot.
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