Occasionally, just occasionally, a car comes along which is as near perfection as it is humanly possible to get. I expected a lot from the latest Porsche 911 and was not disappointed. In Carrera 4S guise the Type 997 is a mighty car, a coupé supreme which is equally at home blistering along an autobahn or tackling a torturous B-road where grip, poise, handling and power meld into an orchestra of driving delight.For £69,900 you'd expect to get an impressive package. You do. The latest Carrera 4S has the grip of a manic kart, the poise of a single-seater and supercar top speed. The rear-mounted 3.8-litre flat-six is a heavyweight boxer. It revs to 7300rpm and drives the 2+2 to 179mph - but that statistic simply gives a taste of the 911's breathtaking ability.With 355bhp punched out at 6000rpm and massive torque of 295lb/ft peaking at 4600rpm, I saw rest to 62mph arrive at a near warp-speed 4.8 seconds and 100mph on the clock 6.4 seconds later. This is a car which can cover the standing kilometre in just 23.5 seconds and do it all without the slightest indication of drama or tyre slip.Porsche has perfected its four-wheel drive system. There's always a minimum 5% of power being fed to the front wheels, but when performance rises and surface friction falls up to 40% can be diverted up front. It's a seamless transfer and throughout my 500-mile test there was never any feeling of front wheel tug or undue weight in the steering.The 4S is a joy for the performance driver. Powerful, confidence-inspiring and built like a battleship with the quality of a Swiss watch. There's little to fault on the road. From its updated instrumentation, new cabin trim, external styling changes and selectable suspension setting to its driver feedback, huge brakes and mile-swallowing ability the 1.47-tonne 4S is a superb rendition of the much-loved 911.I challenge any performance driver not to be moved by the teardrop profile of the 911. The curves and flared arches of the 4S add to the dynamism of a car which has become a performance icon. Little has changed on the all-steel body. Hot galvanised inside and out to protect it from corrosion, it is incredibly rigid. Driven fast on an irregularly surfaced B-road there was no hint of scuttle shake. The 4S stayed taut and firm whatever the loading and kept all four wheels in contact with the road.Porsche has reverted to the traditional oval headlamps of earlier 911s - a positive move which suits the car and still manages to deliver powerful dip and main beams. It's been a controversial step back in styling terms - but how else could the 911 have progressed technically and still managed to hang on to its iconic shape and style?The Stuttgart stylists have worked wonders by staying true to the original 911 lines. They've done it so well it's hard to notice the 22mm flaring on each side to accommodate the massive 19" alloys. The front rims are handsome 8Js shod with 235/35 rubber rated for ZR, but at the back the wheels grow to 11J to cope with a 305/50 ZR-rated tyre. It looks brilliant from the rear and helps get the power down onto the tarmac through the latest six-speed manual transmission.I can't understand why anyone would order this car with sequential Tiptronic. The manual six-speeder's ratios are perfect, changes are slick and through the gears the 3.8 on full cry is a hair-standing delight. But no car is without its minor irritations. The Sport setting on the dampers is a waste of time - it turns the 4S into a jittery milk trolley. Far too nervous and uncomfortable. Leave it in the Comfort setting.Then there's the rear seats. Seats? Only if you want to punish children or cripple adults. They are hard, unyielding leather trimmed benches with near vertical backrests and squabs which cook the posterior of any unfortunate as engine heat percolates through the structure. Use the +2 feature of this stunning coupe for jackets or odd bits of shopping; as a place for humankind they are a bone-folding joke.Not that you can level that criticism at the sumptuous front seats. They are the ultimate in sports car comfort - hugging, supportive and easy to enter and leave. They make the 911 experience all the more enjoyable. Comfort is excellent and the re-modelled interior with its brushed aluminium trim is a relaxed place to live and use.Despite its colossal speed potential the 4S managed to disprove the myth of cars in this class. I didn't have to drive like a thing possessed to enjoy the masterpiece. Using its handling, power and precision at legal speeds on challenging roads proved a sheer delight. It's nice to know the potential is there - it's even better when it delivers all of its fantastic ability at lower velocities.On test I coaxed an average of 23mpg from the Carrera 4S. That's good for around 340 miles on a full tank, but at Group 20 insurance and a demanding maintenance schedule, this Teutonic titan will not be cheap to run. But if you can afford it the Carrera 4S will reward you with technological excellence, grace, poise and driving satisfaction only a handful of road cars can deliver. Engine 3824cc, 6 cylinders Power 355bhp Transmission 6-speed manual Fuel/CO2 23.9mpg / 286g/km Acceleration 0-62mph: 4.8 seconds Top speed 179mph Price £69,900 Details correct at publication date