Engine: 3.8-litre, flat six with direct fuel injection
Power: 385bhp and 310lb.ft.
Performance: 0 to 62mph in 4.7 seconds and 185mph
Fuel economy: 26.9mpg (combined)
CO2 emissions: 247g/km
WHEN the Typhoon jet—the RAF's most advanced fighter—was developed the aeronautical boffins made it deliberately unstable.
Without its myriad of on-board computers it would, I am reliably informed, simply fall out of the sky. With them, it is the most agile weapon of its kind.
Little did Ferdinand Porsche realise when he first created his Porsche 64 sports car that he would be stumbling across such a method of design.
With its engine way out behind the rear wheels and rear wheel drive it should have been wholly unstable, its uneven weight distribution dumping it off the road backward at the first sight of a corner.
The poise it offered, however, won fans world-wide and after 60 years that rear-engined design remains at the heart of the world's most enduring, popular and usable day-to-day sports car.
In 2009's four-wheel-drive 'S' form, Porsche's legendary Carrera shows how a car can defy the laws of physics just as ably as a fighter jet with £13 billion of development beneath its panels.
Packing 385bhp the latest incarnation of Porsche's 997 Carrera 4S boasts the ability to accelerate to 62mph in just 4.7 seconds and on to 185mph.
At the rear, tyres more than a foot wide and gratuitously flared rear wheel arches make no secret of that rear bias.
But, in recent years, the Carrera has forged a reputation as being usable, reliable and sure-footed.
Stepping into the £73,146 C4S I settle into comfortable and supportive leather seats. The interior is basic without being stark, functional without being uncomfortable.
Adjusting the rear view mirrors those bulbous haunches loom into view and I settle into a low driving position, arms comfortably bent along with my left leg, allowing for the 997's long clutch travel.
Depressing the clutch and turning the key ignites the 3.8-litre flat six engine and it's mechanical engine note—dry and rasping it chunters busily.
Porsche claim the new direct injection engine brings fuel consumption of 26.9mpg and CO2 emissions of 247g/km—8.5 per cent more power but 12.9 per cent less thirst and 15.4 emissions than its predecessor.
The C4S begins to show its quality the moment a wheel is turned in the weight and precision communicated by its controls.
The clutch and gearshift are perfectly balanced with reassuring feel and reliable engagement.
A distinctive 911 poise is held by the chassis. The front end bobs gently, appearing worryingly light and combined with that planted rear end, bringing fears of chronic understeer.
Instead it seems to sniff out a line and turning into a corner to explore the limits of this floaty-feeling helm reveals unexpected grip and immediacy.
That gentle bobbing doesn't translate into understeer. The front end is every bit a match for the rear end's heavily tyred traction.
As information about the road surface flows through the thin-rimmed leather steering wheel it's easy to feel the C4S settle before the reassurance of that four-wheel-drive system allows you to feed in the power early.
Porsche Traction Management, which replaces the former all-wheel drive with its viscous multiple-plate clutch, can shuffle up to 100 per cent of power to the front or rear ensuring maximum traction.
Some of those rear-engined characteristics remain, however.
The Carrera's unique weight distribution brings a rearward balance often lacking in four-wheel-drive sports cars. A sense that the rear of the C4S can be adjusted on the brakes or the throttle.
The 911 purists who remember the days when Stuttgart's finest automotive import would reward such playful antics by spitting you into a hedge backwards might suggest that such malleability has no place in a Porsche but from behind the wheel the ability to play brings an addictive dose of sensory overload.
As confidence grows the progression on the brakes and the bellow of the hard-revving flat six as it breaks through 5,000rpm become hard to resist.
Opening the taps elicits and immediate response and, as the rasping engine opens its lungs to whooshing baritone, the pace simply piles on.
The quality and immediacy of the cars response to every input bringing fantastic visceral rewards.
The 2009 C4S communicates its years of painstaking development at every turn—it's deep rooted quality inspiring confidence.
Sure, it wasn't always the case. Once upon a time 911s were feared and revered for their inability to suffer fools.
But after 60 years development, however, it's as polished a weapon you are likely to find on our roads...