The first turbocharged engine was built in 1910 by the firm of Murray-Willat. The concept was embraced by the aviation industry, which required an effective means of compensating for the loss of power caused by reduced oxygen levels during high-altitude flight. Porsche was among the first to recognise other benefits of the technology, including higher performance potential from relatively small displacement engines. This would lead to the development of powerful new engines with very modest dimensions and weight.
The basic principle of a turbocharged engine is to use the exhaust gas flow to drive a radial turbine which in turn drives a compressor in the air intake tract. The rotation of the compressor generates a higher intake pressure, thereby delivering a greater amount of oxygen to the engine. With more oxygen available, more fuel can be burnt, and higher performance can be achieved. The density of the air can be further increased by cooling it prior to combustion. The first ‘intercooler’ device on a production Porsche appeared in 1977 on the 911 Turbo 3.3.
The second 911 Turbo, launched in 1977, developed 300 bhp from a 3.3-litre intercooled engine. Brake performance was similarly enhanced, combining four-piston aluminium fixed calipers with
cross-drilled discs. In 1993, Porsche launched the final 911Turbo to feature dedicated rear-wheel drive. Based on the Type 964 platform, it used a 3.6-litre engine to achieve a major boost in output to 360 bhp. Its Type 993 successor, launched in 1995, set a range of new benchmarks in supercar performance.
All-wheel drive provided greater active safety as well as better driving dynamics. The system also had a rear-axle bias that retained the familiar Porsche handling characteristics. Twin exhaust turbochargers offered better response and a more harmonious build-up of power.The last 911 Turbo to have an aircooled engine, it offered maximum output of 408 bhp from a 3.6-litre displacement. The first water-cooled 911 Turbo, the Type 996, made its debut in the year 2000. Also equipped with all-wheel drive, it used VarioCam Plus to achieve a major improvement in all-round fuel economy. The engine capacity remained at 3.6 litres, while output rose to 420 bhp for a maximum speed of 305 km/h (190 mph). The Type 996 model was the first 911 Turbo with the option of Tiptronic S transmission.
The subsequent launch of the Turbo S version saw a further rise in output to 450 bhp. Now, the evolution of this remarkable car has reached a new pinnacle of achievement. Over the following pages, we will explore every aspect of the new 911 Turbo.
The first Porsche racing car to feature turbocharged power made its debut in the early 1970s. The 12-cylinder engine in the legendary 917 used a twin turbo system to achieve a colossal 1,000 bhp. In 1972, the 917/10 with 5-litre turbo engine claimed the North American CanAm championship. In the following season, the 917/30, developing 1,100 bhp from a 5.4-litre unit, became the most powerful racing Porsche of all time.
This invaluable race experience inevitably found its way into our production road car development. Just one year later, in 1974, the 911Turbo was born. Preceded as it was by the 1973 oil crisis, it was considered a bold undertaking by Porsche. As history would show, it was the first of many surprises in the evolution of this legendary car. The original 911 Turbo featured widened wheel arches as well as specially developed front and rear spoilers. These major aerodynamic refinements were essential requirements given the increased engine performance. Devel oping 260 bhp, the first 911 Turbo could reach 100 km/h (62 mph) in as little as 5.5 seconds. Maximum torque output of 343 Nm was unprecedented in a 3-litre engine. This exceptional performance necessitated a new gearbox design featuring specially reinforced gears. Thus began a new type of Porsche that would soon acquire mythical status.
Engineering the new 911 Turbo
The primary objective for every 911 Turbo is to challenge the limits of technical feasibility. Not only in terms of performance and dynamics, but also when it comes to ride comfort. On this latest evolution, we’ve completely redesigned a number of systems and components. The result builds on the achievements of the previous 911 Turbo – a car widely acknowledged as the ultimate in sportscar design.
As you would expect, the new 911 Turbo meets the highest expectations in terms of engine performance. The classic flat-six unit develops 353 kW (480 bhp) at 6,000 rpm from a 3.6-litre displacement. Maximum torque of 620 Nm is available between 1,950 and 5,000 rpm. To achieve
that capability, we’ve combined VarioCam Plus with twin turbocharger units featuring Variable Turbine Geometry (VTG) – a totally new technology on a petrol-engined car. With a standard manual gearbox, the new 911Turbo requires just 3.9 seconds to reach 100 km/h (62 mph). Equipped with the latest optional Tiptronic S transmission, the car is 0.2 seconds quicker on the standard sprint. Benchmark times to 200 km/h (124 mph) are 12.8 and 12.2 seconds, respectively. Maximum speed with either transmission is 310 km/h (193 mph).
One of the most important engine technologies, appearing for the first time on a Porsche, is Variable Turbine Geometry (see page 32). The main components on this system are the adjustable guide vanes which channel the exhaust flow onto the turbines, enabling higher turbine speeds at lower engine rpm. The most difficult challenge when developing this technology was the high exhaustgas temperature of around 1,000 ºC, which is unique to a petrol engine. This enormous thermal load is considerably greater than the 700 ºC typically encountered on a diesel-powered car. It was only possible to bridge this gap using materials developed for aerospace applications. The primary benefits of Variable Turbine Geometry include faster response, higher torque output from lower engine speeds, and greater top-end power. Maximum torque is also available over a wider engine speed range. By eliminating the problem of ‘turbo lag’, the traditional weakness of the turbocharged engine is finally a thing of the past.
To apply these benefits efficiently to the road, we required another innovation in sportscar design: allwheel drive with Porsche Traction Management (PTM). Using an electronically controlled multi-plate clutch, this intelligent technology provides variable drive to each axle. The front/rear split is continuously adjusted based on current road conditions and driver inputs. Although biased towards the rear, the front receives more power whenever the situation requires.
Porsche Traction Management is specifically designed to optimise driving dynamics. The additional traction provided by both the all-wheel drive system and PTM represents a major improvement in active safety, especially in the wet or on snow. Another benchmark technology on the new 911 Turbo is the standard braking system. The front and rear discs have a generous diameter of 350 mm. On the optional Porsche Ceramic Composite Brake (PCCB), the front diameter is increased to 380 mm.
Other standard features on the new 911 Turbo include a new evolution of Porsche Stability Management (PSM) as well as Porsche Active Suspension Management (PASM) featuring electronic damper control. A limited-slip differential is available for the rear axle as an option. For even greater performance, the car can be equipped with the optional Sport Chrono Package Turbo. Key features include an ‘overboost’ function which provides as much as 60 Nm of additional torque under acceleration. When the throttle is fully open, the boost pressure is increased temporarily by approximately 0.2 bar. The electronic throttle map is also adjusted to give a more dynamic response to pedal inputs.
Other modifications when ‘Sport’ mode is selected include a major rise in the trigger threshold used by Porsche Stability Management (PSM). The all-wheel drive system featuring PTM provides a similar increase in driver involvement by sending a greater proportion of drive torque directly to the rear wheels. PASM provides a stiffer suspension setup enabling faster turn-in and better road contact.
Another major development on the new 911 Turbo is the car’s lightweight design and construction.The doors and front lid are made from aluminium which offers a range of benefits
in terms of both performance and economy. Every gram of weight on every component is there for a specific reason.
As a result, the standard model (with six-speed manual gearbox) weighs just 1,585 kg. Even more impressive are the power-toweight ratio of 302.8 bhp per tonne and surprisingly low fuel consumption. This powerful potential is, of course, matched by exemplary ride quality on every type of road. This rare combination of performance and comfort is one of the distinguishing features of the 911 Turbo.
The standard Bi-Xenon headlights with integral cleaning system are compact, stylish and elegantly incorporated within the new front-end design. The front apron moulding is an entirely new development, featuring highperformance LED indicators in the outer air intake ducts. The compact front foglights are neatly positioned on the outer edges of the front apron.
The side air intakes, to the rear of the doors, provide optimum air delivery to the twin intercooler units. Equally efficient are the cooling air ducts to the front and rear brake assemblies. This enhanced cooling action is an important factor in the excellent performance of the standard braking system.
The body of the car is much wider across the rear than the front. A generous wheel track is combined with wider tyres to achieve enormous lateral grip. The engine lid is another totally new design and features an integral bi-plane rear spoiler. The upper wing element is automatically raised at approximately 120 km/h (75 mph) and lowered at around 60 km/h (37 mph).The rear apron moulding has also been redesigned to blend with the rest of the car. The side air outlets and fully enclosed twin tailpipes are a further indication of the power within. Black plastic sills along the sides of the body provide effective protection against stone chips. Elegantly matched to the exterior of the car is the all-new wheel design. The 19-inch forged alloys have a standard two-tone finish as well as wide, low-profile tyres.
The standard tyre dimensions are 235/35 ZR 19 (front) and 305/30 ZR 19 (rear). The interior of the car is equally compelling and entirely designed around the driver. The high-quality surfaces include a full leather finish on the standard electric seats as well as the dashboard, doors and rear side panels. Two sports seat options are also available, one featuring adaptive adjustment. The standard equipment package includes a new gear-knob design – created exclusively for the 911 Turbo –and a three-spoke sports steering wheel featuring 40 mm of height and reach adjustment. The overall design of the new 911 Turbo marks another new phase in the ongoing evolution of this remarkable car. Wholly integral to the fundamental vehicle concept, every detail is a direct expression of power, composure and comfort.
A characteristic design feature of the new 911 Turbo is the modified front end with its distinctive, tautly drawn cooling air inlets. In conjunction with the standard-equipment oval bi-xenon headlights, they define its unmistakable image. The harmonious front view is enhanced by widely placed and deep-set fog lights and by new LED flashers, which are situated in the lateral air inlets of the front end. From the rear perspective too, the Turbo takes on a more powerful appearance. This is due first and foremost to its tail end, 22 millimeters wider than that of the previous model, to which the redesigned wing spoiler element has been aligned. It now slopes downward slightly at the sides to nestle into the contours of the rear fenders. The lateral air inlets behind the doors have also been redrawn and, together with the new air ducts, afford a more efficient supply of cooling air to the charge-air intercoolers.
In the USA the Type 997 911 Turbo is priced at 122,900 Dollars (not including taxes), and will be available as from July 8, 2006.
In addition to the 911 Turbo, as a special surprise at the Geneva Motor Show, Porsche will be presenting another world premiere: the new 911 GT3. You will receive technical data and photos of this “racing car for the road” on February 28, 2006, the first press day in Geneva.
The 911 Turbo (Type 997) now has an output of 480 bhp at 6,000 revolutions per minute, 60 bhp more than its predecessor (Type 996). The specific output of the 3.6-litre boxer engine thus climbs to a new all-time high 133 bhp per liter of displacement. Rated torque has been increased from 413 to 457 lbs-ft. The speed range in which this power is available has also been extended. While the previous model’s maximum torque was available between 2,700 and 4,600 revolutions per minute, the corresponding figures are now 1,950 to 5,000 revs.
These improvements are translated into driving performance. The Porsche 997 Turbo with six-speed manual transmission requires 3.9 seconds for the standard sprint from zero to 62mph. The coupé reaches the 124 mph mark in 12.8 seconds. And just 3.8 seconds are all it takes for the most powerful series-built 911 model of all time to accelerate from 50 to 75 mph in fifth gear. Despite these enhanced performance statistics, Porsche developers succeeded in reducing average fuel consumption by one tenth to 12.8 liters per 100 62 miles.
The 911 Turbo (997) with the optionally available Tiptronic S automatic transmission puts in an even more impressive performance. An optimized setup gives the vehicle the wherewithal to power from zero to one hundred in just 3.7 seconds and to reach 124 mph after a mere 12.2 seconds.
The Turbo with automatic transmission also has the advantage when it comes to flexibility. In penultimate gear it accelerates from 50 to 75 mph in 3.5 seconds. Fuel consumption by the Tiptronic S variant is 0.3 liters lower than that of its predecessor: 13.6 liters in accordance with the EU standard. Both transmission variants have a top speed of 192 mph.
The vehicle’s flexibility can be enhanced even further with the optional “Sport Chrono Package Turbo”, available for the first time. Here the driver selects the “sports button” adjacent to the gear lever to activate a short-time “overboost” at full throttle. This increases boost pressure in the mid speed range by 0.2 bar for up to ten seconds; torque rises from 60 to 680 Newtonmeters. The time required by the 997 Turbo with manual transmission for intermediate acceleration from 80 to 120 km/h is reduced by 0.3 seconds to 3.5 seconds.
These performance figures owe themselves to exhaust turbochargers with variable turbine geometry, featuring for the first time in a gasoline engine model. At the heart of this technology are adjustable guide blades, which direct the engine exhaust flow variably and precisely onto the turbine wheel of the exhaust turbocharger. The principle of variable turbine geometry unites the advantages of small and large exhaust turbochargers and leads to a discernable improvement in flexibility and acceleration, particularly at low speeds.
To transfer the available power to the road, the new generation of the 911 Turbo features a redesigned all-wheel drive with an electronically controlled multi-disc clutch. Porsche Traction Management (PTM) ensures variable power distribution to the two driven axles. Depending on the driving conditions, the all-wheel electronics system constantly determine the optimal torque distribution to ensure the best-possible drive. In practice this translates as high agility on narrow country roads, outstanding traction in rain and snow and optimal active safety even at high speeds. These properties make the Porsche Traction Management system in the 997 Turbo one of the most powerful and, at the same time, lightest all-wheel systems on the market.
The new 911 Turbo’s driving performance is duly tempered by its brake system, which comprises monobloc fixed-caliper disc brakes with six pistons at the front axle and four at the rear.
In comparison with the Type 996, the diameter of the internally ventilated and perforated brake discs at the front and rear wheels has been increased by 20 millimeters to 350 millimeters. As an option, Porsche is also offering its optimized ceramic brake system, PCCB (Porsche Ceramic Composite Brake). The advantages of this high-tech material mean a reduction of 37 lbs compared to the standard brake system, excellent fading stability owing to consistent friction values and absolute corrosion resistance. The brakes now have a diameter of 380 millimeters at the front axle and 350 millimeters at the rear.