A COMPELLING blend of refinement and performance has been put together by Mercedes-Benz with the new C 63 AMG sports saloon.

It's the quickest C-Class variant to date and powered by a biturbo V8 engine which in S specification develops a potent 510 horsepower

Unleash its might and it can blast the car from 0 to 60 in just 4.0 seconds and puts the AMG at the top of the pile, outrunning the BMW M3 or any hot Audi.

The C 63 S saloon costs from £66,810 while a slightly less powerful version boosted to ‘only' 476 horsepower is priced from £60,060. Estates cost just over £1,000 more.

As such the C 63 AMG becomes the flagship of the C-Class range which is soon to expand with the arrival of sleek looking coupe models.

But even as a saloon the C 63 AMG is styled to impress with wider wings and pronounced air scoops at the front and a dramatic tail featuring four exhausts.

It looks very different to a standard C-Class and the design is emphasised with a wide front grille, plenty of brightwork and two power bulges on the bonnet - an AMG trait.

That's a clue to the firepower and so are the V8 biturbo badges on the front wings.

As a brand which specialises in performance, AMG has become expert at turbo technology and has developed a series of highly efficient engines that deliver as much punch as the monster 6.0-litre plus blocks of old while shedding their gas-guzzling image.

The new engine in the latest C 63 is a 4.0-litre V8 and like every other AMG engine is hand assembled at its workshops in Affalterbach, not far from the Mercedes' headquarters in Stuttgart.

Honed to perfection producing more than 500 horsepower from four litres is no mean achievement and in the C 63 S the engine is impeccably well behaved.

Around town it is smooth and very manageable yet when the conditions allow for its potential to be explored in depth it is awe inspiring.

Under acceleration the sound is a symphony of all that is great about V8s and the handling sublime.

The C 63 has its own steering and suspension set up and it feels like a proper performance car should - nicely weighted and well in balance.

The experience is compounded by a fairly chunky steering wheel - complete with flat bottom and a white lock band - and paddle shifters for the seven speed auto box which require a positive action to change gear. There is nothing prissy about this car and it is obvious it means business.

Despite the hardcore credentials the cockpit is plush and pure Mercedes with high tech controls operated from a tablet-like display screen that sits on the dash.

Sculpted sports seats dominate the front but in the back it is a proper three seater and there's no loss of boot space from the regular C-Class.

In the centre console, and right to hand for the driver, are multi-mode controls which can alter the C 63's characteristics through four distinct settings from comfort to a full-blown track configuration where the automatic stability functions are minimal allowing the car to strut its own stuff.

There's also an individual setting where a driver's personal preferences for feel can be stored and engaged in an instant.

For cruising choose the comfort mode but it is at its best in sport mode where the added tautness and quicker throttle response makes all the difference.

Compared to the previous generation the C 63 S saloon has more than 10 per cent extra power and a similar hike in acceleration.

Nevertheless, economy is better and 26 to the gallon is likely to be a real world figure thanks to a stop/start function which reduces its thirst in traffic.

Mercedes claims an official fuel return of 34.5mpg with emissions of 192g/km - a huge step forward from the days when unleashing an AMG would see fuel figures in the low teens.

The new C 63 is the most refined saloon AMG has developed and a top rate high performance saloon for modern motoring.

Previous incarnations have been very much full on but this is a car that can be enjoyed under all circumstances while still making the transition from everyday to extraordinary in the blink of an eye.