Although the C4S has the Turbo look, it isn't an exact copy. It lacks the wrap-over rear spoiler and air intakes ahead of the rear wheels (there aren't any turbo intercoolers to feed) and thus looks much cleaner. To balance downforce with the C4S's smaller, Carrera-style flip-up rear spoiler, Porsche's aerodynamics engineers have tweaked the lower lip of the front spoiler, although its wider frontal area means the C4S is a few mph slower than the stock C4 flat-out.

Inside nothing much has changed, save the fact that it's fully leather- trimmed. Indeed, the C4S comes with a brimming standard specification that includes Porsche Stability Management (PSM), electric seats, upgraded stereo and metallic paint plus the 18in wheels and tyres and bigger, red-callipered brakes from the Turbo. This makes it pretty good value at ΂£62,260, or ΂£3090 more than the stock C4.

Personally, I'd resist ordering my C4S with one of the colourful leather interiors. The cockpit of our test car came in a terracotta hue and we saw another one in turquoise. The colour coding is so extensive that it looks like a can of paint has been exploded inside the car and the masking of the dials and other small patches has been peeled off later, like that episode of Mr Bean where he paints his living room.

Twist the key and the exhaust note of the flat-six seems a bit gutsier, a bit bassier than that of the C2 we've included in the eCOTY feature, though the only apparent difference is the C4S's slightly fatter, Turbo-style chrome-lipped tailpipes. Otherwise, once you're rolling you're hard-pushed to tell you aren't in the standard Carrera, which means a supple ride and the usual quality feel to the steering, pedals and gearshift.

According to Porsche, the extra grip and stronger braking of the C4S give it a Nurburgring lap time of 8min 16sec, or four seconds quicker than the Carrera 2. The suggestion is that the Turbo-look isn't just for show and makes the C4S a better proposition for track days, which makes sense, I guess.

However, decent roads were in short supply around the launch HQ in Brescia, northern Italy, the choice being restricted to slow, smooth, wide and semi-urban or slow, mildly bumpy and sinuous up in the hills. Not exactly the ideal setting for attempting to quantify fully the losses and gains of the wide-body chassis against standard.
What I can say is that the C4S has a nicely planted feel, as if it's keyed into the road in a way that the Turbo and C2 aren't. There's no more feel through the steering but both ends feel grippy and the overall balance and poise is impressive. Although it's got the 18in rims and fat rubber of the Turbo, the Carrera 4S gets its own unique suspension settings, including slightly softer springs, thinner anti-roll bars and re-rated dampers.

It's easy to get into the groove and build up a natural rhythm, swinging easily through a rapid-fire sequences of bends, measuring out precisely controlled slugs of power from the finely responsive, normally aspirated flat-six.

Although far from a definitive test, this taster seems to suggest that the C4S is an appealing addition to the burgeoning 911 range, not just a Turbo look-alike for those who can't afford the real thing. It also shows that the Carrera remains a sensitive creature that can feel distinctly different dependent on the detail of its chassis specification. So, the C4S is more than the sum of its parts. Which is nice.