At a glance, it may look like it's more or less the same car. But, as with every Porsche makeover, it typically involves major updates under the sheet metal. With the Panamera, the latest version of the Porsche limousine has been refreshed with tighter lines for a more defined front end.

At the back, the second-generation car, as Porsche calls it, gets a bit more than cosmetic work.

There is a new boot lid with a wider rear windscreen and redesigned tail lamps.

The licence plate holder is relocated farther down and the boot release is a button on the lower edge of the glass.

From behind, the revised rear end looks more menacing, especially in a dark paint finish.

But more interestingly, the German sports car maker has launched a mind-boggling 10 variants of the Panamera II, including a new three-litre V6 biturbo engine, an enhanced hybrid model and a long wheelbase Executive version.

The new V6 with forced induction is for the mid-range Porsche Panamera S and the four-wheel -drive Panamera 4S.

The Panamera S used to have a naturally aspirated 4.8-litre V8 to drive the rear wheels, and the V6 is derived directly from it. But even with downsizing to save fuel, the V6 still pumps out more impressive numbers - its 420 hp and 520 Nm are 20 hp and 20 Nm higher than the previous V8, with a better zero-to-100 kmh time of 5.1 seconds for the S (down 0.3 second) and 4.8 seconds for the 4S (down 0.2 second). Top speed is also slightly higher, up 4 kmh to 286 kmh.

Yet, all this is accomplished with an 18 per cent improvement in fuel economy at 8.9 litres per 100 km under the combined cycle.

In the 4S, the most perceptible difference is the engine's higher level of refinement. Together with enhanced insulation, the latest Panamera is almost silent at cruising speeds. To equal the smoothness of the V8, a balancer shaft was added to the twin-turbo V6. Only under hard acceleration is the engine sound heard. Mated to the seven-speed PDK dual-clutch transmission, the Panamera 4S is the uber-sports saloon. The PDK is ultra-sensitive in any mode - Normal, Sport or Sport Plus. Just a tap of the accelerator will get the gearbox downshifting immediately.

The transmission also has a new party trick - virtual gears.

When driving at a constant speed of around 80 kmh, the two wet clutches are allowed to slip to reduce engine revs and increase fuel economy. This is different from the by-now familiar coasting function which disengages the gearbox from the engine when cruising.

But it is the PDK's responsiveness and speed that make the Panamera 4S such an engaging drive. It adapts to all road situations quickly, and with all-wheel-drive stability to maximise traction and variable damping, the big Porsche is stable and confident on winding country roads.

The V6 is shorter than the V8, so the Panamera's centre of gravity is shifted slightly backwards, thus improving overall balance and handling.

The free-revving V6 is also a joy to listen to. The acoustic treatment involves using a diaphragm to transmit induction air sounds into the cabin, accompanied by an exhaust flap which opens wider when the Sport button is pressed.

The Porsche Panamera has always been the luxuriously sporty alternative. With the latest technological improvements, this big and comfortable four-seater limousine has the privilege of being more frugal without sacrificing any power.

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