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 Car of the Century, the 911 came fifth after the Ford Model T, the Mini, the Citroën DS and the Volkswagen Beetle. It is the most successful surviving application of the air (or water) cooled opposed rear engine layout pioneered by its original ancestor, the Volkswagen Beetle.
The air cooled series of engines (1964 - 1998)
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 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 aluminum doors, a magnesium crankcase, twin-spark cylinder heads, and a power output of 210 PS (154 kW).
In 1969 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 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)
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 911E and 911S used mechanical fuel injection (MFI) in all markets. The 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 CIS-powered cars are usually referred to as "1973.5" models by enthusiasts.
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 a tremendous effort was made to improve the handling of the 911. Due to the 911's unusual engine placement (rear-mounted, with most of the vehicle's weight concentrated over the rear axle) early 911's were prone to over steer when driven at the limit, and could easily spin in the hands of an inexperienced driver. In an attempt to remedy this, Porsche relocated 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 8 liters of oil from outside the wheelbase to inside, improving weight distribution and thus, 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 petrol station attendants were putting petrol in the oil tank. The oil tank was subsequently moved back to its original position for the 1973 model year, and remained there until it was moved back within the wheelbase for the 964 models.
911S models also gained a discreet spoiler under the front bumper to improve high-speed stability. With the car's weight only 1050 kg (2315 lb), these are often regarded as the best classic mainstream 911s. For racing at this time, the 911 ST was produced in limited numbers (the production run for the ST only lasted from 1970 to 1971.) 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 (1973 and 1974)
These models, much prized by collectors, are considered by many to be the greatest all-time classic 911s. RS means Rennsport in German, meaning motorsport or circuit racing. The Carrera name was reintroduced from the 356 Carrera which had itself been named after Porsche's victories in the Carrera Panamericana races in Mexico in the 1950s. The RS 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 2.7 RS had a larger engine (2687 cc) developing 210 PS (154 kW) with MFI, revised and stiffened suspension, a "ducktail" rear spoiler, larger brakes, wider rear wheels and rear wings. In RS Touring form it weighed 1075 kg, in Sport Lightweight form it was about 100 kg lighter, the saving coming from the thin-gauge steel used for parts of the bodyshell and also the use of thinner glass. In total 1580 were made, comfortably exceeding the 500 that had to be made to qualify for the vital FIA Group 4 class. 49 Carrera RS cars were built with 2808 cc engines producing 300 PS.
In 1974, Porsche created the Carrera RS 3.0 with K-Jetronic Bosch fuel injection producing 230 PS. It was almost twice as expensive as the 2.7 RS but offered a fair amount of racing capability for that price. The chassis was largely similar to that of the 1973 Carrera RSR and the brake system was from the Porsche 917. The use of thin metal plate panels and a spartan interior enabled the shipping weight to be reduced to around 900 kilograms.
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 turbo charging.
911 2.7-litre / G, H, I and J series (1974-1977)
The 930 Turbo was introduced in 1975 (see below).
The Carrera 3.0 was introduced in 1976 with what was essentially the Turbo's 2994 cc engine minus the turbocharger, and with K-Jetronic CIS although now developing 200 PS (147 kW).
The well known problem of pulled cylinder head studs with the K-Jetronic 2.7 engine only occurred in hot climates. This emerged in 1975 in California where thermal reactors, aimed at reducing emissions, were fitted below the cylinder heads thus causing massive heat build up around the magnesium crankcase and then made worse by the lean running K-Jetronic CIS. The fitting of a 5 blade engine fan instead of the usual 11 blade further compounded the situation. Bearing in mind Porsche's largest market being the USA, the 930 Turbo, Carrera 3.0 and all subsequent models used aluminium alloy crankcases which were around 15 lbs heavier.
The Bosch K-Jetronic CIS varied fuel pressure to the injectors dependent on the mass airflow. While this system was exceedingly reliable, it did not allow the use of as "hot" cams as MFI or carburettors allowed. Therefore the 911S's horsepower decreased from 190 to 175 despite the displacement increase from 2.4 to 2.7 L. However, the engine did have increased drivability. The 210 PS Carrera 2.7 with MFI was not sold in the US owing to emission regulations -instead they received a 'Carrera' fitted with a 911S engine producing 175 PS, later reduced to 165, and in California even down to 160 PS.
Also produced for the 1976 "model year", for the U.S. market, was the 912E, a 4-cylinder version of the 911 like the 912 that had last been produced in 1969. It used the I-serced. In 1976 the Porsche 924 took this car's place for the 1977 "model year" and beyond. The power was supplied by a 4 cylinder high performance fuel injection motor also used in the 411 Volkswagen. Less than 6000 were built.
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 approved 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) (1974–1989)
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)
SCs sold in the UK could be specified with the Sport Group Package (UK) which added stiffer suspension, the rear spoiler, front rubber lip 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 America 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)
The non-Turbo models became available as "Turbo-look" or "Super Sport" in 1984, a style that resembled the Turbo with wide wheel arches and the "whale-tail", it also featured the stiffer turbo suspension and the four piston aluminium brembo calipers with the bigger, drilled and vented, disks found on the turbo models and developed from the Porsche 917 brakes. The Super Sport also had the wider turbo wheels. 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 which was evocative of the Porsche 356 Speedster of the 1950s, was produced in limited numbers. The 1987 Carrera Club Sport, of which 340 were produced, is a collectible 911 that had a blueprinted engine with a higher rev limit, and had the electric windows, electric seats, and radio deleted to save a claimed 50 kg in weight.
964 Series (1989-1993)
Based with many innovation technologies from the 959 model, this would be a very important car for Porsche, since the world economy was undergoing recession and the company could not rely on its image alone. It was launched as the Carrera 4, the "4" indicating four-wheel-drive, a decision that surprised many but demonstrated the company's commitment to engineering by reminding buyers that race and rally engineering (of the 959) does affect road cars. Drag coefficient was down to 0.32. A rear spoiler deployed at high speed, preserving the purity of line when the vehicle was at rest. The chassis was redesigned overall. Coil springs, ABS brakes and power steering made their debut. The engine was increased in size to 3600 cc and developed 250 PS (184 kW). The car was more refined, but thought by some journalists to have lost some purity of the 911's concept. The rear-wheel-drive version, the Carrera 2, arrived a year later.
The 964 incarnation of the 911 Turbo returned in 1990 after an absence from the price lists. Using a refined 3.3 L engine of the previous Turbo, but two years later a turbo engine based on the 3.6 L engine of the other models was introduced.
In 1989, Porsche introduced the ahead-of-its-time Tiptronic automatic transmission in the 964 Carrera 2, featuring adaptive electronic management and full manual control. The 964 was one of the first cars in the world offered with dual airbags standard (from 1991), the first being the Porsche 944 turbo (from 1987).
In 1992, Porsche re-introduced a limited-edition RS model, inspired by the 1973 Carrera RS and emissions-legal in Europe only. Appeals from American customers resulted in Porsche developing the RS America of which 701 were built. However, while European RS was a homologation special, RS America was an option delete variant of the regular model. The RS 3.8 of 1993 had Turbo-style bodywork, a larger fixed whale tail in place of the movable rear spoiler, and a 300 PS (221 kW) 3746 cc engine.
Since the RS/RS America was intended as a no-frills, higher performance version of the 964, there were only 4 factory options available: a limited-slip differential, AM/FM cassette stereo, air conditioning, and a sunroof. The interior was more basic than a standard 911 as well; for example the interior door panels lacked the armrests and door pockets and had a simple pull strap for the opening mechanism. Although RS America was about $10,000 cheaper than a fully-equipped C2 at the time of their production, these models now command a premium price on the used market over a standard 964 (RS Europe was about $20,000 more expensive than a C2).
964 Turbo (1990-1993)
In 1990 Porsche introduced a Turbo version of the 964 series. This car is sometimes mistakenly called 965 (this type number actually referred to a stillborn project that would have been a hi-tech turbocharged car in the vein of the 959). For the 1991 and 1992 model years, Porsche produced the 964 Turbo with the 930's proven 3.3 L engine, improved to produce 320 PS (235 kW). 1993 brought the Carrera 2/4's 3.6 L engine, now in turbo-charged form and sending a staggering 360 PS (265 kW) to the rear wheels. With the 993 on the way, this car was produced through 1994 and remains rather rare.
993 Series (1993-1998)
The exterior featured an all new front and rear end, with only the windscreen, side windows and doors maintained from the previous 964. The revised bodywork was smoother, having a noticeably more aerodynamic front end somewhat reminiscent of the 959. Styling was by Englishman Tony Hatter under the supervision of design chief Harm Lagaay.
Along with the revised bodywork, mechanically the 993 also featured an all-new multilink rear suspension that improved the car's ride and handling. This rear suspension was largely derived from the stillborn Porsche 989's rear multilink design, and served to rectify the problems with earlier models' tendency to oversteer if the throttle or brakes were applied while in mid-corner.
The new suspension, along with chassis refinements, enabled the car to keep up dynamically with the competition. Engine capacity remained at 3.6 L, but power rose to 272 PS (200 kW) thanks to better engine management and exhaust design, and beginning with model year 1996 to 286 PS (210 kW). The 993 was the first Porsche to debut variable-length intake runners with the "Varioram" system on 1996 models. This addressed the inherent compromise between high-RPM power production and low-RPM torque production, and was one of the first of its kind to be employed on production vehicles. A new four-wheel-drive made a return as an option in the form of the Carrera 4, the rear wheel drive versions simply being called Carrera. A lightweight RS version saw capacity rise to 3.8 L, with power reaching 300 PS (221 kW). The RS version had rear-wheel drive only.
Non-turbo models appeared that used the Turbo's wide bodyshell and some other components (the Carrera 4S and later the Carrera S).
The rare Targa open-topped model also made a return, this time with a large glass roof that slid under the rear window. The highly prized air-cooled 993 Targa had a limited release between 1996-1998.
993 Turbo (1995-1998)
A Turbo version of the 993 was launched in 1995 and became the first standard production Porsche with twin exhaust turbochargers and the first 911 Turbo to be equipped with permanent all-wheel-drive (in order to delete the 4WD, one had to refer to the more powerful and race homologated GT2). The similarity in specification and in performance levels inspired several comparison road tests with the Porsche 959 (f.e. Car and Driver, July 1997, p. 63). The 3.6 liter twin turbo M64/60 engine produced 408 hp (DIN).
Water-Cooled Engines (1998-Present)
996 Series (1998-2004)
Pundits criticized the 996's styling a great deal, largely because it shared its headlamps—indeed much of its front end, mechanically—with the less expensive Boxster. The 996 had been on the drawing board first and was a more advanced car in some respects, but the cost-cutting seemed inappropriate for an expensive car. Otherwise, the Pinky Lai-penned shape followed the original Butzi Porsche design very closely. The interior was further criticized for its plainness and its lack of relationship to prior 911 interiors, although this came largely from owners of older 911s.
The Type 996 spawned over a dozen variations, including all wheel drive Carrera 4 and Carrera 4S (which had a 'Turbo look') models, the club racing-oriented GT3, and the forced-induction 996 Turbo and GT2. The Turbo, four-wheel-drive and twin-turbo, often made appearances in magazines' lists of the best cars on sale.
996 GT3 RS
The Carrera and Carrera 4 underwent revisions for model year 2002, receiving the front headlight/indicator lights which were first seen on the Turbo version two years earlier. This allowed the 911 to be more distinguishable from the Boxster. A mildly revised front fascia was also introduced, though the basic architecture remained.
Engine wise, displacement was 3.4L and power 300 PS (221 kW), increased in 2002 to 3.6L and 320 f vPS (235 kW).
996 GT3 (1999-2004)
Porsche unveiled a road-going GT3 version of the 996 series which was derived from the racing GT3. Simply called GT3, the car featured lightweight materials inside and out, including thinner windows, the GT3 was a lighter and more focused 911 with the emphasis on handling and performance. The suspension was lower and more aggressive than other 996s, leading to excellent handling and razor-sharp steering though the ride was very firm. Of more significance was the engine used in the GT3. Instead of using a version of the water-cooled units found in other 996s, the naturally-aspirated engine was derived from the Porsche 911 GT1-98 sports-prototype racing car and featured lightweight materials which enabled the engine to rev highly.
996 Turbo (2000-2004)
In 2000, Porsche launched the Turbo version of the Type 996. Like the GT3, the new Turbo engine derived from the 911 GT1 engine and, like its predecessor, featured twin-turbos and now developed 420 PS (309 kW). Also like its predecessor the new Turbo was only available with all wheel drive. A 17,000 USD factory option, the X50 package, was available that boosted the engine output to a tidy 450 PS with 620 Nm (457 lb/ft) of torque across a wide section of the power band. With the X50 package in place the car could make 0-100 km/h (0-62 mph) in 4.1 seconds. This package is named as Turbo S in Europe.
Styling-wise, the car was more individual than previous Turbos. Along with the traditional wider rear wings, the 996 Turbo had different front lights and bumpers when compared to the Carrera and Carrera 4. The rear bumper had air vents that were reminiscent of those on the Porsche 959 and there were large vents on the front bumper, which have been copied on the Carrera 4S and Cayenne Turbo.
997 Series (2005-Present)
The Turbo version of the 997 series featured the same 3.6 L twin-turbocharged engine as the 996 Turbo, but this time it developed 480 HP (353 kW) and 620 N·m (457 lbf·ft) of torque. This was in part due to the 997's new variable-geometry turbocharger, which essentially combines the low-rev boost and quick responses of a small turbocharger with the high-rev power of a larger turbocharger. As well as producing more power and flexibility, the new turbocharger improved fuel consumption over the 996 Turbo. With these performance upgrades, it accelerates to 100 km/h (62mph) in 3.9 seconds (3.7 with the Tiptronic transmission) and reaches a top speed of 310 km/h (193 mph). However, these are official figures and Porsche is notable for being conservative about their power and performance ratings. Motor Trend Magazine has clocked the 997 Turbo's 0-60MPH time in 3.2 seconds with the Tiptronic S transmission. The optional Sports Chrono overboost package increases torque to 680 N·m (505 lbf.ft) for short periods (maximum 10 seconds) but over a narrower rev range.
The 997 Turbo features a new all wheel drive system, similar to the one found on the Porsche Cayenne. Featuring PTM (Porsche Traction Management) the new system incorporates a clutch-based system which varies the amount of torque to the front wheels, regardless of wheel slip front and rear. This, according to Porsche, aids traction and the handling by redirecting the torque to control oversteer or understeer, thus resulting in far more neutral handling, as well as greatly improved performance in all weather conditions (as opposed to older AWD system which gave the Turbo stability under hard acceleration).
Styling wise, as with the 996 Turbo the car featured more unique styling cues over the Carreras, one of the more distinctive elements the front LED driving/parking/indicator lights mounted on a horizontal bar across the air intakes. The traditional rear wing is a variation of the 996 bi-plane unit.
The 911 GT3, announced on February 24, 2006 is reported to accelerate 0-100 km/h in 4.3 seconds and have a top speed of 310 km/h (193 mph), almost as quick as the Turbo. Porsche's factory reports can be conservative though; Excellence magazine tested the 997 GT3 and recorded 0-100 km/h in 3.9 seconds and a top speed of 312 km/h (194 mph). The 997 GT3 was released in the summer of 2006. It was recently crowned "the best handling car" by Motor Trend.
The GT2 variant of the 997 has been spotted in testing around the Nürburgring. The car shares much of its bodywork with the Turbo but has a different rear spoiler and extra venting for the radiator. While no official specifications have been released, Car and Driver speculates that the car will have around 525 hp, 51hp more than the Turbo (based on the fact that the 996 GT2 also had 51 hp more than the equivalent Turbo).