 30
years after the launch of the first 911 Turbo, the Turbo is still a
senior core member of the 911 family. Throughout the years, 911 Turbo
evolved from 3.0 to 3.6 litres, single turbo to twin-turbo, from
mechanical wastegate to electronic boost control, from 260 horsepower
to 420 horsepower, rear-drive to all-wheel-drive…. Watching the
evolution of this car just like studying the history of automotive
technology. Today, the 996 Turbo is an astonishingly quick and refined
sports car. Many people say it is close to perfect. What can be
improved? The answer from Weissach is: even more power and even more
refinement.Before introducing the 997 Turbo, let us talk about the market positioning of this car. Priced at £100,000 in the UK market, the Turbo rivals Ferrari F430 (£120,000) and Lambo Gallardo (£120,000), although luxury grand tourers like Aston Martin DB9 (£110,000), BMW M6 (£80,000) and Mercedes SL55 / 65 AMG (£100,000 / £150,000) may also present threats. Besides, there is internal competition from 911 GT3 (£80,000) and GT2 (est £130,000). However, both the GT3 and GT2 are lightweight road and track dual-purpose sports cars aimed at very hardcore drivers, while the Turbo is a pure road car for daily use. It has more luxury features and sound-deadening than both, not to mention the all-weather security from its 4WD system. 997 Generation  As in the case for Carrera, the
997 Turbo is a small evolution from 996 Turbo, unlike the mutation from
993 to 996. Outside, the most obvious change is the return to
traditional round headlamps. Then you can see it has many ventilation
holes enlarged for better cooling, while the bi-plane electric rear
spoiler has been widened. As a result, aerodynamic lift has been
reduced slightly while drag coefficient remains unchanged at 0.31. The 997's steel monocoque chassis is believed to be slightly stiffer than the last generation. It also gains 22mm in width to enhance cornering prowess. The suspensions get electronic adaptive damping like the Carrera. The brakes have been enlarged from 330mm to 350mm all round, with 6-pot front and 4-pot rear calipers. As before, ceramic composite brakes are optional (they cost some £6,000 !). Another major improvement is the 4WD system. Previously it employed a passive viscous coupling to send torque to the front wheels when the rear wheels slip. Now it is replaced by an electronic-controlled multi-plate clutch. This mean the PTM (Porsche Traction Management) program can redistribute power between the front and rear axle at any time to correct undesirable under / oversteer.  These
enhancements inevitably add weight. Although Porsche compensates with
the use of aluminum doors, the new Turbo still got an extra 45
kilograms, taking the kerb weight to 1585 kg. That is 135 kg heavier
than the all-aluminum Ferrari F430, but still comfortably lighter than
other grand tourers like BMW M6 and Aston Martin DB9.Every time Porsche allowed weight increase must accompany with even more gain in power. The 997 Turbo is no exception. Although its 24-valve water-cooled boxer engine keeps capacity unchanged at 3600cc (we predicted it to grow to 3.8 litres), as is the Variocam-Plus variable valve timing and lift system, it gets a pair of new variable geometry turbochargers developed by BorgWarner (which acquired KKK in 1998). It is said to be the world's first VTG turbo for petrol engines, whose exhaust gas is much hotter than diesel engines thus requires specially-developed, heating-resisting vanes. The variable exhaust vane geometry makes better use of the exhaust flow regardless of rpm, thus improve turbo response at low rev and increase power at high rev. As a result, the 3.6-litre twin-turbo engine pumps out 480 horsepower at 6000 rpm, 60 horses up from the 996 Turbo, or just 3 horses shy of the outgoing GT2. The new engine is also much more torquey and flexible. It produces 457 lbft from 1950-5000 rpm, versus the old car's 413 lbft / 2700-4600 rpm. If this is not enough, an optional Sport program offers a 10-second overboost of 0.2 bar, taking the max torque to 501 lbft for strong overtaking. With the stronger engine, the new Turbo can run to 193mph (up from 190mph), accelerate from 0-60mph in 3.8 seconds (down from 4.1 sec) and 0-124mph in 12.8 seconds (down from 14.5 sec). Quite unbelievably, Porsche claims the car equipped with 6-speed Tiptronic S automatic transmission is even quicker – 0-60mph in 3.6 sec and 0-124mph in 12.2 sec. This is because the computers of the gearbox and VTG turbochargers can communicate with each other to optimize acceleration. On the Road  The beauty of 911 Turbo is the
combination of astonishing speed and handling with an easily livable
manner. It satisfies the definition of super sports cars and grand
tourers simultaneously. Apart from the recent Ferrari 599GTB, I can't
think of any other cars have such achievement. The 997 Turbo is very fast, no question. There are not many cars on this planet can do 0-60mph in 3.8 seconds and 0-100mph under 9 seconds. Ferrari F430 can. Lamborghini Gallardo cannot. Even the mighty 959 supercar is eclipsed by it, although you might ask why the Turbo took 20 years of development to do so. Porsche's twin-turbo flat-six is very different from its rivals' naturally-aspirated V8 or V10. It sounds subdued, even too quiet for a sports car. But it generates massive torque from very low rpm and carry on until 6000rpm. The wide power band means you don't need to rev it to deliver performance. The VTG turbochargers have virtually no lag. The boxer engine runs smoothly. It does not appear to have any temper, just work quietly and efficiently to push the car forward. No doubt it is a German product. Handling can be summarized in a few words: massive grip, fool-proof traction, first-class braking, excellent body control and composure. For sure, 911 Turbo is not a lightweight, but it hides its weight very well. Its compact size is a strong card in narrow twisties. Its strong brakes are confidence inspiring, as is the accurate and meaty steering. Rearward weight bias seems totally irrelevant to its excellent dynamic balance, thanks to the 40 years of experience of tuning its suspensions, tires and traction system. Yes, its handling is not as sharp as GT3, but its cornering prowess is equally high and definitely more secured, thanks to the clever 4-wheel-drive system. On wet surfaces or roads you are not familiar with, the Turbo is always the best companion to go with.  On the other hand, the 911
Turbo is also a very comfortable grand tourer. Its PASM adaptive
suspensions has the choice of comfort mode and sport mode to suit
different purposes. In comfort mode, ride compliance can shame many
high-performance grand tourers such as BMW M6 and Aston DB9.Then there is a spacious cabin, the luxury features (power seats and windows, climate control, sound and navigation system, leather upholstery) and plenty of luggage space (in case you fold down the dog seats). The Turbo is a comfortable long-distance GT. That said, there is something missing in the car – emotion. Compare to Ferrari F430 or Lamborghini Gallardo, the Porsche turbocharged flat-6 is too civilized in the way it sings and the way it responds to throttle input. It is therefore less inspiring to drive. Ditto the 4WD handling, which is probably too safe. Remove some understeer and add some more feel to the steering will bring more excitement. But then you know Porsche has already got such car – GT3. As we always know, for pure driving pleasure there is no replacement to a naturally aspirated engine and rear-wheel drive. |
| The above report was last updated on 22 Jun 2006. All Rights Reserved. |
