第1个回答 2008-02-12
The Porsche 911 (pronounced as nine eleven) is a sports car made by Porsche AG of Stuttgart, Germany. The famous, distinctive and durable car has undergone continuous development since its introduction in 1964. Mechanically it is notable for being rear engined and, until the introduction of the all-new Type 996 in 1999, air-cooled. All 911s use six-cylinder boxer engines.
Since its inception the 911 has been modified, both by private teams and the factory itself, for racing, rallying and other types of automotive competition. It is often cited as the most successful competition car ever, especially when its variations are included, mainly the powerful 935.
In the international poll for the award of the world's most influential car of the twentieth century the 911 came fifth after the Ford Model T, the Mini, the Citroën DS and the Volkswagen Beetle.
■■History
A note on designations: the series letter (A, B, C, etc.) is used by Porsche to indicate the revision for production cars. It often changes annually to reflect changes for the new model year. The first 911 models are the 'A series', the first 993 cars are the 'R series'.)
A note on the models listed: not all of the Porsche 911 models ever produced are mentioned here. The listed models are notable for their role in the advancements in technology and their influence on the following vehicles from Porsche.
A note on model names: although the articles below use Porsche's internal classifications (911, 964, 993, 996, 997) the car was always sold as 911. "Carrera", "GT3", "Turbo", etc. refer to the specific model trim (they are all 911s).
■■Air-Cooled Engines (1964 - 1998)
●911 Series (1964-1989)
The 911 was developed as a much more powerful, larger, more comfortable replacement for the Porsche 356, the company's first model, and essentially a sporting evolution of the Volkswagen Beetle. The new car made its public debut at the 1963 Internationale Automobil-Ausstellung, better known to English speakers as the Frankfurt motor show.
It was designated as the 'Porsche 901' (901 being its internal project number). Peugeot protested on the grounds that they owned the trademark to all car names formed by three numbers with a zero in the middle. So, before production started, the new Porsche had its name changed to 911. It went on sale in 1964.
——911 2.0-litre / O, A and B series (1964-1969)
The earliest editions of the 911 had a 130 PS1 (96 kW) six-cylinder engine, in the 'boxer' configuration like the 356, air-cooled and rear-mounted, displaced 1991 cc compared with the 356's four-cylinder 1600 cc unit. The car had four seats although the rear seats are very small, and the car is usually called a 2+2 rather than a four-seater (the 356 was also a 2+2). It was mated to a five speed manual 'Type 901' transmission. The styling was largely by Ferdinand "Butzi" Porsche, son of Ferdinand "Ferry" Porsche. Erwin Komenda, the leader of the Porsche car body construction department, was also involved in the design.
The 356 came to the end of its production life in 1965, but there was still a market for a 4-cylinder car, particularly in the USA. The Porsche 912, introduced the same year, served as a direct replacement. It used the 356's 4-cylinder, 1600 cc 90 PS (66 kW) engine but wore the 911 bodywork.
In 1966 Porsche introduced the more powerful 911S, the engine's power raised to 160 PS (118 kW). Alloy wheels from Fuchs, in a distinctive 5-leaf design, were offered for the first time. In motorsport at the same time, installed in the mid-engined Porsche 904 and Porsche 906, the engine was developed to 210 PS (154 kW).
In 1967 the Targa version was introduced. The Targa had a removable roof panel, a removable plastic rear window (although a fixed glass version was offered alongside from 1968) and a stainless steel-clad roll bar. (Porsche had, at one point, thought that the NHTSA would outlaw fully open convertibles in the US, an important market for the 911, and introduced the Targa as a 'stop gap' model.) The name 'Targa' came from the Targa Florio road race in Sicily, in which Porsche had notable success: victories in 1956, 1959, 1960, 1963, 1964, 1966, 1967, 1968, 1969, 1970 and 1973.
The 110 PS (81 kW) 911T was also launched in 1967 and effectively replaced the 912. The staple 130 PS (96 kW) model was renamed the 911L. More excitingly, the 911R was produced in tiny numbers (20 in all). This was a lightweight racing version with thin aluminium doors, a magnesium crankcase, twin-spark cylinder heads, and a power output of 210 PS (154 kW).
In 1968 the B series was introduced: the wheelbase for all 911 and 912 models was increased from 2211 mm to 2268 mm, an effective remedy to the car's nervous handling at the limit. The overall length of the car did not change: rather, the rear wheels were relocated aft. Fuel injection arrived for the 911S and for a new middle model, 911E. A semi-automatic Sportomatic [1] model, composed of a torque converter, an automatic clutch, and the four speed transmission, was added to the product lineup.
——911 2.2-litre / C and D series (1970-1971)
For the 1970 model year the engines of all 911s was increased to 2195 cc. Power outputs were uprated to 125 PS (92 kW) in the 911T, 155 PS (114 kW) in the 911E, and 180 PS (118 kW) in the 911S. The 912 was discontinued, thanks to the introduction of the Porsche 914 as an entry model.
The 2.2 L 911E was called "The secret weapon from Zuffenhausen". Despite the lower power output of the 911E (155 PS) compared to the 911S (180 PS) the 911E was quicker in acceleration up to 160 km/h (100 mph).
——911 2.4-litre / E and F series (1972-1973)
The 1972-1973 model years consisted of the same models of 911—the entry level T, the midrange E and the top of the line S. However, all models got a new, larger 2341 cc/142 in³ engine. This is universally known as the "2.4 L" engine, despite its displacement being closer to 2.3 litres — perhaps to emphasize the increase over the 2.2. The new power ratings were 130 PS (96 kW), or 140 hp (104 kW) in the U.S., for the T, 165 PS (121 kW) for the E and 190 PS (140 kW) for the S.
The 911E and 911S used mechanical fuel injection (MFI) in all markets. The US 911T 911T was carbureted, except in the US where it also used MFI, which accounts for the 7 kW power difference between the two. In January, 1973, US 911Ts were switched to the new K-Jetronic CIS (Continuous Fuel Injection) system from Bosch. These cars are commonly referred to as 1973.5 models.
With the power and torque increases, the 2.4 L cars also got a newer, stronger transmission, identified by its Porsche type number 915. Derived from the transmission in the Porsche 908 race car, the 915 did away with the 901/911 transmission's 'dog-leg' style first gear arrangement, opting for a traditional H pattern with first gear up to the left, second gear underneath first, etc. Some say this was because the dog-leg shift to second gear was inconvenient for in town driving, other say it was due to Porsche’s desire to put 5th gear outside the main transmission housing where it could easily be changed for different races. The Sportomatic transmission was still available, but only as a special order.
In 1972 tremendous effort was made to improve the handling of the 911. One thing Porsche did was relocate the oil tank from its position behind the right rear wheel to in front of it. This had the effect of moving the weight of almost 9 quarts of oil from outside the wheelbase to inside, improving the handling. To facilitate filling of the oil tank, Porsche installed an oil filler door (much like the fuel filler door on the left front fender) on the right rear quarter panel. Unfortunately, this unique design was scrapped after only one year, some say because inattentive gas station attendants were putting gas in the oil tank! The oil tank was moved back to its original position for the 1973 model year, and there is stayed until it was moved back within the wheelbase for the 964 models.
These cars also gained a discreet spoiler under the front bumper to help high-speed stability. With the car's weight only 1050 kg (2314 lb), these are often regarded as the best classic mainstream 911s. For racing at this time, the 911 ST was made in tiny numbers. The cars were available with engines of either 2466 cc or 2492 cc, producing 270 PS (199 kW) at 8000 rpm. Weight was down to 960 kg. The cars had success at the Daytona 6 Hours, the Sebring 12 Hours, the 1000Km Nurburgring and the Targa Florio.
——911 Carrera RS 2.7 (1972-1974)
This model, much prized by collectors, is one of the all-time classic 911s. It was built so that Porsche could enter racing formulae that demanded that a certain minimum number of production cars were made. Compared with a standard 911S, the Carrera RS had a larger engine (2687 cc) developing 210 PS (154 kW), revised and stiffened suspension, a 'ducktail' rear spoiler, larger brakes, larger wheels & wheel-arches, and was about 150 kg lighter — most of the saving coming from the thin-gauge steel used for parts of the bodyshell. In total 1636 were made, comfortably exceeding the 500 that had to be made to qualify for the vital FIA Group 4 class. A more powerful version, the Carrera RS 3.0, was also made. The 3.0 L cars used standard-gauge steel, and thanks to that extra 180 kg the extra 20 PS (15 kW) did not give it a performance advantage.
The Carrera RSR 3.0 and Carrera RSR Turbo (its 2.1 L engine due to a 1.4x equivalency formula) were made in tiny numbers for racing. The turbo car came second at the 24 Hours of Le Mans in 1974, a significant event in that its engine would form the basis of many future Porsche assaults on sportscar racing, and can be regarded as the start of its commitment to turbocharging. The large rear spoiler and the 3.0 turbo engine were to be used again in the production 911 Turbo and the 934 racing car.
——911 2.7-litre / G, H, I and J series (1974-1977)
From 1974 a detuned version of the 2687 cc engine from the Carrera RS was used in the mainstream production cars. The cars looked rather different from the previous year's, thanks to bulky new bumpers front and rear, to conform with low-speed impact protection requirements of US law. The interior was refreshed too. The model line-up was now: 911, 911S and 911 Carrera (the latter now a regular production model). The Turbo was introduced in 1975 (see below). In 1976 the Carrera model was upgraded to what was essentially the Turbo's 2992 cc engine, minus the turbocharger, developing 200 PS (147 kW). The 2.7 engines proved to be less reliable than the 'bulletproof' 2.4 units. In effect, the 2.4 L engine had been enlarged with no additional cooling capacity. The engines saw problems, particularly in hot climates, where the different rates of thermal expansion between the magnesium of the crankcase and the aluminium of the cylinder heads contributed to major failure. In addition, some engines saw problems whereby the cylinder head studs would pull themselves out of the crankcase. The 3.0 L engine of the Turbo and Carrera had not used magnesium, but rather aluminium, thereby showing equal expansion rates to the cylinders. The move to that engine across the board was welcome for reliability reasons. However, the aluminium case weighed 15 lb more than the magnesium one. In addition with the 1973.5 engines Porsche moved away from MFI to Bosch K-Jetronic CIS. This system varied fuel pressure to the injectors dependant on the mass airflow. While this system was exceedingly reliable, it did not allow the use of as "hot" cams as MFI or carburators allowed. Therefore the 911S's horsepower decreased from 190 to 165 despite the displacement increase from 2.4 to 2.7 L. However, the engine did have increased drivability.
Also produced for the 1976 "model year", for the U.S. market, was the 912E, a 4-cylinder version of the 911 like the old 912 that had last been produced in 1969. It used the I-series chassis and the 2.0 Volkswagen engine from the Porsche 914. In all, 2099 units were produced. In 1976 the Porsche 924 took this car's place for the 1977 "model year" and beyond.
——Position vis-à-vis the Porsche 928
Although Porsche was continuing development of the 911, executives were troubled by its declining sales numbers and in 1971 greenlighted work on the Porsche 928. Larger, with a front-mounted V8 engine that was considerably more powerful than the contemporary 911's, the 928 was not only designed to eclipse its performance, it was designed to be a more comfortable car, a sporty grand tourer rather than a focused sports car. The 928 sold reasonably well, and managed to survive from its introduction in 1977 until 1995. Throughout its 17 years, despite its capabilities on the road, it never outsold the 911. Notably, it achieved little success in racing.
——911 Turbo (Type 930) (1975-1989)
In 1975 Porsche introduced the first production turbocharged 911. Although called simply Porsche 911 Turbo in Europe, it was marketed as Porsche 930 (930 being its internal type number) in North America. The body shape is distinctive thanks to wide wheel-arches to accommodate the wide tyres, and a large rear spoiler often known as a 'whale tail' on the early cars, and 'tea-tray' on the later ones. Starting out with a 3.0-litre engine (260 PS or 191 kW), it rose to 3.3 L (300 PS or 221 kW) for 1978. The early cars are known for extreme turbo lag.
Production figures of the car soon qualified its racing incarnation for FIA Group 4 competition as the Porsche 934, of 1976. Many participated at Le Mans and other races including some epic battles with the BMW 3.0 CSL 'Batmobile'. The wilder Porsche 935, a more highly tuned car in FIA Group 5 and evolved from the 2.1 L RSR Turbo of 1974, was campaigned in 1976 by the factory and won Le Mans in 1979. Private teams continued to compete successfully with the car until well into the 1980s.
As demand for the Turbo soared in the late 1980s, Porsche introduced novelty variants including a slant-nose version, while not significantly improving the range mechanically. Although these cars could be sold for extraordinary premiums over the standard models, the company's reluctance to invest in research and development of the entire 911 line at that time turned out to be an almost fatal decision not only for the 911, but for the entire company.
Only in its last production year the 930 was equipped with a five-speed gearbox. Before, the five-speed gearboxes of the naturally-aspirated cars were not strong enough to cope with the torque of the turbo engines. With the four-speed gearbox the 930 was capable of exceeding 200 km/h (125 mph) in third gear!
There have been turbocharged variants of each subsequent generation of 911. Four-wheel-drive was standard from the 993 Generation and on, except for the lightweight GT2.
——911 SC (1978-1983)
SC stands for "Super Carrera" (although Porsche never claimed this or marketed it as such). All 911 models standardized on the 2994 cc engine for late 1977. This engine was a unit fresh from the factory delivering 180 PS (132 kW) that was still capable of substantial extra tuning, compared with the 2.7 which was almost at its limit. Yet, the weight of the extra equipment on these cars was blunting performance compared with what would have been expected from earlier, lighter cars with the same power output.
SCs sold in the UK could be specified with the Sport Group Package (UK) which added the rear spoiler, front air dam and black Fuchs wheels.
In 1981 a Cabriolet concept car was shown at the Frankfurt motorshow. Not only was the car a drop top, but it also featured four-wheel drive. In late 1982 (débuting as the 1983 model) the first 911 cabriolet went on sale (the first Porsche cabriolet since the 356). To many, this was a much more attractive car than the Targa, the other open-top 911. But while the Targa was priced to match the regular car, the Cabriolet cost significantly more. Cabriolet versions of the 911 have been offered ever since.
In 1979 Porsche made plans to replace the 911 with the 928, but the 911 still sold so much better than the 928, that Porsche revised its strategy and inject new life into the Type 911 European editions. Those cars (1981-1983 911 SCs) were massaged to yield 204 bhp @ 5900 rpm from their 2994 cc powerplants. North Americans would have to wait for the replacement 3.2 L 911 Carrera in 1984 before seeing any extra horsepower.
——911 3.2 Carrera (1984-1989)
In 1984 a new 3.2 L car replaced the 3.0 L SC model. It was badged '911 Carrera' but known as '3.2 Carrera', the first time the sporty label had been applied to the basic 911. Power was increased, brakes were better, the fuel injection was upgraded to enhance everyday reliability, and the car was more refined. The non-Turbo models became available as 'Turbo-look' or 'Super Sport', a style that aped the Turbo with wide wheel-arches and the 'whale-tail', but did not reflect any mechanical changes.
In 1987, the Carrera got a new five-speed gearbox sourced from Getrag, model number G50. This included a hydraulic clutch.
The 911 Speedster, a low-roof version of the Cabriolet, evocative of the Porsche 356 Speedster of the 1950s, was produced in limited numbers. The Carrera Club Sport from 1987 (340 produced) is highly collectible. It was stripped of electric windows, electric seats, and radio to save a claimed 50 kg in weight. Its engine was allowed to rev higher, and the engine developed a little more power.
Innovation and experimentation have been at the heart of Rolls-Royce’s philosophy for more than a century. Driven by the uncompromising quest for perfection instilled by its founder, Sir Henry Royce, the company’s enduring commitment to exceptional engineering is best exemplified by its long tradition of ‘EX’ Experimental cars.
In 1919, Rolls-Royce Motor Cars built 1EX, its first experimental car. Based on a Silver Ghost chassis, it was used a rolling test bed to develop ideas and engineering solutions that would be incorporated into later generations of production Rolls-Royce cars. A succession of EX cars followed over the next 40 years, culminating in the 45EX of 1958.
After a hiatus of some 46 years, it’s a revitalised Rolls-Royce Motor Cars that has revived the EX tradition, with two bold experimental cars. The first - 100EX - was the product of a desire both to celebrate the company’s centenary in 2004, and to build on the groundbreaking technology pioneered by the company’s new Phantom road car. The second, and most recent - 101EX - is an equally adventurous machine albeit with a very different character.
With increasing technological challenges and demanding customer expectations, the value of EX is stronger now than ever. By exploring adventurous themes, advanced concepts and bold technology through living, breathing cars like 100 and 101EX, Rolls-Royce remains at the forefront of automotive design and engineering.