Review: Porsche 911 Turbo

Every new succession of the Porsche 911 has traditionally been more of an evolution of the previous model rather than a complete redesign, but to imagine that engineers could build a 911 Turbo better than the 996 version nearly seemed impossible. Not so, as Stuttgart’s finest have amazed us once again with a car that’s more powerful and faster than the previous 996, and every bit as usable. In fact, the new 997 Turbo’s most amazing feat is the confidence-inspiring levels of usability, which manages to flatter even the most average of drivers.

Styling and Interior

Since its introduction in 1974, the 911 Turbo has always differed from the regular models beyond just a mechanical view point but also an aesthetic one. The latest model is no exception. An aggressive front bumper, muscular fenders and gaping air intakes are all trademarks of a classic Turbo model, while unique 19in alloys plus an adjustable rear spoiler that automatically rises at speeds in excess of 120km/h solidify the look of the new car. The interior remains much the same as the rest of the 911 fleet, apart from the ‘Turbo’ labelling, silver and LED highlights of the gauge cluster, and digital boost gauge integrated into the tacho.

For the rest of the interior, there’s not much difference between it and the base Carrera, which is already widely appreciated for its superb cabin and comfortable and supportive sports buckets. The seats themselves are a big leap over those of the previous 996, now featuring adjustable height and headrests, lumbar support, and a position memory function for the driver. Despite the Turbo’s sporting connotations accessories like automatic climate control, CD stereo and sat-nav remain and are located at the base of the center console.

Technical

The basic structure of the familiar six-cylinder boxer engine remains virtually unchanged with the powerplant of the previous 996. Instead, most of the changes involve the adoption of the variable turbine geometry (VTG) turbochargers whose internal vanes directly modify the passage of exhaust gases to vary the amount of air flow through the turbo depending on the level of revs coming from the engine. In effect, this makes the engine much more responsive lower in the rev range and provides good power delivery right through till the ends of the tachometer. The VTG technology has already been proven a success with diesel powered cars, but in the case of the petrol powered six-cylinder 997 Turbo there were fears that the main turbo unit wouldn’t be able to withstand exhaust temps in excess of 1,000°C (modern turbodiesel exhaust temps are around 700-800°C). The problem was solved by employing special heat resistant material and the use of new methods of simulation that allowed engineers to design and test turbo components before mass production. In addition, the conventional method of using oil to draw heat from the turbo has been added to the engine’s water cooling system. Maximum power is 480hp at 6,000rpm with torque of 620Nm coming on from just 1,950rpm.

Even more power is available for models equipped with the optional Sports Chrono Package. Pressing the Sport button on the center console makes several adjustments to the engine management and suspension settings, providing more response thanks to Porsche’s new Overboost function. With the throttle floored, the blades of the VTG turbo are angled so that they increase boost pressure by 2.9psi for up to 10 seconds, increasing peak torque to an earth moving 680Nm. When accelerating from 80 to 120km/h in fifth gear, our recorded times fell from 3.8 seconds to 3.5 seconds with Overboost switched on.

Porsche also offers VarioCam Plus valve-lift technology for its entire 911 range, a valve-timing system that optimizes engine breathing and refinement, while reducing fuel consumption and exhaust emissions. During low load situations valve-lift is limited to just 3.6mm, reducing friction and resulting in a 10% improvement for emissions and fuel consumption over the 996 mill. At the other end of the scale, when power is demanded, valve-lift is increased to a maximum of 11mm, which ensures efficient air flow and minimal losses.

On the road

Power delivery arrives very early in the rev range, with usable thrust coming from as low as 2,000rpm. When the digital pointer of the boost gauge moves from zero and the needle of the tachometer passes the 2,800 mark, passengers better grab a hold of something because this is the point where all hell breaks loose. The acceleration becomes uncontrollable, and in a very short time you’ll be reaching dizzying speeds. For example, after 22.49 seconds, or just 1,065m from the starting point, the 997 Porsche 911 Turbo has reached 250km/h, the kind of performance that only a few years ago had been limited to the rarefied world of supercars.

The torque curve gives a clear indication of the characteristics of the six-cylinder boxer, not only from its peak of 620Nm, but because this force remains constant from 1,950 until 5,000rpm – a significant leap over the previous 996 Turbo’s narrower torque spread between 2,700 and 4,600rpm. In practical terms, less gear changes are required because of the strong acceleration in any gear. Even when travelling at 40km/h in sixth, we could accelerate effortlessly without any interruptions all the way to the recorded 310.6km/h top speed. Numbers for the acceleration figures are equally dizzying as those of the top speeds. While the previous 996 Turbo took only 4.32 seconds for the 0-100km/h dash and 22.95 seconds for the standing kilometre, the new 997 version does the same in just 3.76 seconds and 21.37 seconds respectively.

Apart from the momentous powerplant, the new 911 Turbo and the rest of the AWD 911 range for the matter has been improved significantly over its predecessors because of two key changes. These include refinements to the PASM (Porsche Active Suspension Management) and the addition of an electronically controlled, hydraulically actuated multidisc clutch for transfer of engine torque through the coupe’s AWD system. With the changes applied, the 911 Turbo maintains amazing levels of stability and traction through corners and only becomes unsettled with a heavy foot to the throttle. Reaching the limits of this super-Porsche is not easy. The behaviour of the car is so balanced with only the slightest level of understeer creating some uneasiness when accelerating out of a corner in the lower gears. A dab of the throttle quickly results in oversteer as weight shifts from the rear-axle to the front of the chassis, causing the tail to slip and requiring a firm hand at the wheel to keep it in line. With the electronic aids disabled, exiting a corner while pressing the accelerator will undoubtedly run some risk.

Thankfully, Porsche has some of the best brakes in the business and bringing this 3483 pound beauty to a standstill is no sweat for the excellent but very pricey ceramic-composite brake discs. Six-piston callipers bite pizza-sized 15in discs up front, working with smaller four-piston callipers and 13.8 discs in the rear. Stopping power is extremely strong once the brakes are warmed up, but modulating deceleration smoothly can be a challenge and it’s not uncommon to experience the front brakes locking up and ABS going into overdrive.

Should I buy one?

The engine of the new 911 Turbo alone is worth every extra penny over the Carrera S. Throw in the car’s dramatic styling, amazing performance, class-leading brakes and superb AWD system, and the US$122,900 asking price starts to look like a relative bargain. Then there’s the intangible feeling that this new coupe truly belongs in the same league as the best supercars and could even be regarded as a step above because of the way it allows anyone to hop in and take full advantage of its performance credentials. Porsche engineers have outdone themselves once again with the latest 911 Turbo but with an even more powerful Turbo S in the works, one question arises - have they lifted the bar too far?



Edisport Editoriale Spa