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126-406: A top fuel dragster accelerates from a standstill to 100 mph (160.9 km/h) in as little as 0.8 seconds (less than one third the time required by a production Porsche 911 Turbo to reach 60 mph (96.6 km/h)) and can exceed 297 mph (478.0 km/h) in just 660 feet (201.2 m). This subjects the driver to an average acceleration of about 4.0  g 0 (39  m/s ) over

252-572: A magnesium crankcase, twin overhead camshafts, and a power output of 210 PS (154 kW; 207 hp). A clutchless semi-automatic Sportomatic model, composed of a torque converter , an automatic clutch , and the four-speed transmission was added in Autumn 1967. It was canceled after the 1980 model year partly because of the elimination of a forward gear to make it a three-speed. The B series went into production in August 1968, replacing

378-420: A "fueler" engine will provide power over a very broad range from very lean to very rich mixtures. Thus, to attain maximum performance, before each race, by varying the level of fuel supplied to the engine, the mechanical crew may select power outputs barely below the limits of tire traction. Power outputs which create tire slippage will "smoke the tires" and as a result the race is often lost. The air/fuel mixture

504-456: A 2+2). A four or five-speed "Type 901" manual transmission was available. The styling was largely penned by Ferdinand "Butzi" Porsche, son of Ferdinand "Ferry" Porsche . Butzi Porsche initially came up with a notchback design with proper space for seating two rear passengers but Ferry Porsche insisted that the 356's successor was to use its fastback styling. 7 prototypes were built based on Butzi Porsche's original design and were internally called

630-405: A 3.2-litre horizontally opposed flat 6-cylinder unit, was utilized. At the time Porsche claimed it was 80% new. The new swept volume of 3,164 cc was achieved using the 95 mm (3.7 in) bore (from the previous SC model) combined with the 1978 Turbo 3.3 crankshaft's 74.4 mm (2.9 in) stroke. In addition, higher domed pistons increased the compression ratio from 9.8 to 10.3:1 (9.5:1 for

756-557: A 5-speed 915 transmission. Originally power output was 180 PS (132 kW; 178 hp), later 191 PS (140 kW; 188 hp) and then in 1981 it was increased to 204 PS (150 kW; 201 hp). The move to an aluminium engine was to regain case reliability, something missing for many years with magnesium. In 1981 a Cabriolet concept car was introduced at the Frankfurt Motor Show . The convertible body design also featured four-wheel drive , although this

882-492: A K-Jetronic 2.7-litre. The 911S 2.7 engine was rated during the entire lifespan at 175 hp (130 kW; 177 PS). The Carrera 2.7 model built for all markets, except for the United States, used the 210 PS (150 kW; 210 hp) RS 911/83 engine with Bosch mechanical fuel injection pump from the 1973 Carrera RS. These Carrera 2.7 MFI models were built from 1974 until 1976 and were mechanically identical to

1008-440: A car owner who often runs NHRA races in the United States. Before their run, racers often perform a burnout to clean and heat tires. The burnout also applies a layer of fresh rubber to the track surface, improving traction during launch. At maximum throttle and RPM, the exhaust gases escaping from a dragster's open headers produce about 900–1,100 pounds-force (4.0–4.9 kN) of downforce . The massive airfoil over and behind

1134-409: A chart on the wall of Professor Bott's office. It depicted the ongoing development schedules for the three primary Porsche product lines: 944 , 928 and 911. Two of them stretched far into the future, but the 911 program stopped at the end of 1981. I remember rising from my chair, walking over to the chart, taking a black marker pen, and extending the 911 program bar clean off the chart. I am sure I heard

1260-536: A hammer. It was further investigated and described by Harry Ricardo during experiments carried out between 1916 and 1919 to discover the reason for failures in aircraft engines . Under ideal conditions the common internal combustion engine burns the fuel/air mixture in the cylinder in an orderly and controlled fashion. The combustion is started by the spark plug some 10 to 40 crankshaft degrees prior to top dead center (TDC), depending on many factors including engine speed and load. This ignition advance allows time for

1386-458: A high thermal efficiency . Since the onset of knock is sensitive to the in-cylinder pressure, temperature and autoignition chemistry associated with the local mixture compositions within the combustion chamber, simulations which account for all of these aspects have thus proven most effective in determining knock operating limits and enabling engineers to determine the most appropriate operating strategy. The objective of knock control strategies

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1512-558: A major purse, the Cragar - Weld Top Fuel Classic and "Big Daddy" Don Garlits returned to Top Fuel full-time. By 1987, NHRA Top Fuel Funny Car was drawing twice as many entrants as positions available. In 2012 enclosed cockpits were allowed to be used regularly used in top fuel by the NHRA. Porsche 911 Turbo The Porsche 911 (pronounced Nine Eleven or in German : Neunelf )

1638-405: A more complete mixing of fuel and air. Diesels actually do not suffer exactly the same "knock" as gasoline engines since the cause is known to be only the very fast rate of pressure rise, not unstable combustion. Diesel fuels are actually very prone to knock in gasoline engines but in the diesel engine there is no time for knock to occur because the fuel is only oxidized during the expansion cycle. In

1764-408: A much lower energy density (11.2 MJ/kg (1.21 Mcal th /lb)) than either gasoline (44 MJ/kg (4.8 Mcal th /lb)) or methanol (22.7 MJ/kg (2.46 Mcal th /lb)), an engine burning nitromethane can produce up to 2.4 times as much power as an engine burning gasoline. This is made possible by the fact that, in addition to fuel, an engine needs oxygen in order to generate force:

1890-878: A period of 3.8 seconds. Much of organized drag-racing is sanctioned by the National Hot Rod Association. Since 1955, the association has held regional and national events (typically organized as single elimination tournaments, with the winner of each two car race advancing) and has set rules for safety, with the more powerful cars requiring ever more safety equipment. Typical safety equipment for contemporary top fuel dragsters: full face helmets with fitted HANS devices ; multi-point, quick release safety restraint harness; full body fire suit made of Nomex or similar material, complete with face mask, gloves, socks, shoes, and outer sock-like boots, all made of fire-resistant materials; on board fire extinguishers; kevlar or other synthetic "bullet-proof" blankets around

2016-646: A power output of 270 PS (200 kW; 270 hp) at 8,000 rpm. Weight was down to 960 kg (2,120 lb). The cars had success at the Daytona 6 Hours, the Sebring 12 Hours , the 1000 km Nürburgring , and the Targa Florio . RS stands for Rennsport in German, meaning race sport . The Carrera name was reintroduced from the 356 Carrera which had itself been named after Porsche's class victories in

2142-678: A qualifying session at Old Bridge Township Raceway Park in Englishtown, New Jersey . The shortening of the distance was used by the FIA at some tracks, and as of 2012 is now the standard Top Fuel distance defined by the FIA. The International Hot Rod Association , which at the time sanctioned Top Fuel in Australia, dropped the 1/4-mile distance in September 2017 after a campaign by Santo Rapisarda,

2268-784: A significant event in that its engine would form the basis of many future Porsche attempts in sports car racing. This, and the earlier 917, was Porsche's commitment to turbocharger applications in its cars. There is a common misconception that all 911s built between 1974 and 1989 are 'G-series' cars. In fact, the G-series was only produced for the 1974 model year. It was followed by the H, J, K, and so on. Model year 1974 (G Series. Aug. 1973 to July 1974 production) Model year 1975 (H Series. Aug. 1974 to July 1975 production) Model year 1976 (J Series. Aug. 1975 to July 1976 production) Model year 1977 (K Series. Aug. 1976 to July 1977 production) The 1974 model year brought many significant changes to

2394-605: A silent cheer from Professor Bott, and I knew I had done the right thing. The Porsche 911, the company icon, had been saved, and I believe the company was saved with it. The replacement for the SC series came in 1984 as the 911 3.2 Carrera, reviving the Carrera name for the first time since 1977. This was the last iteration in the original 911 series, with all subsequent models featuring new body styling and new brake, electronic, and suspension technologies. A new higher-displacement engine,

2520-463: A timer-based retard system is used. The engine is fitted with eight individual open exhaust pipes, 2.75 in (69.85 mm) in diameter and 18 in (457.20 mm) long. These are made of steel and fitted with thermocouples for measuring of the exhaust gas temperature . They are called "zoomies" and exhaust gases are directed upward and backwards. Exhaust temperature is about 500 °F (260 °C) at idle and 1,796 °F (980 °C) by

2646-488: A variety of classes. It is among the most successful competition cars. In the mid-1970s, the naturally aspirated 911 Carrera RSR won world championship races including Targa Florio and the 24 Hours of Daytona . The 911-derived 935 turbo also won the 24 Hours of Le Mans in 1979. Porsche won the World Championship for Makes in 1976, 1977, 1978, and 1979 with 911-derived models. In a 1999 poll to determine

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2772-533: A way to gain leverage on NHRA, so Nix could use nitro himself). These cars ran in NHRA's S/FX class, variously defined as "Super Factory Experimental" or "Supercharged Factory Experimental". They were shortly turning in E.T.s in the low 11s and trap speeds of over 140 mph (225.3 km/h); at Long Beach on 21 March, an 11.49 pass at 141.66 mph (228.0 km/h) was recorded. Bob Sullivan's Pandemonium (a '65 Plymouth Barracuda ) joined about six other nitro-fuelled early funny cars facing fuel dragsters in

2898-428: Is a result of using very high boost levels and running at extremely high RPMs; both of these stress the internal components to a high degree, meaning that the peak power can only safely be achieved for brief periods of time, and even then only by intentionally sacrificing components. The engine power output can also be calculated based upon the car's weight and its performance. The calculated power output of these engines

3024-432: Is a short lag between the fuel being injected and combustion starting. By this time there is already a quantity of fuel in the combustion chamber which will ignite first in areas of greater oxygen density prior to the combustion of the complete charge. This sudden increase in pressure and temperature causes the distinctive diesel 'knock' or 'clatter', some of which must be allowed for in the engine design. Careful design of

3150-477: Is a two-door 2+2 high performance rear-engined sports car introduced in September 1964 by Porsche AG of Stuttgart , Germany. It has a rear-mounted flat-six engine and originally a torsion bar suspension . The car has been continuously enhanced through the years but the basic concept has remained unchanged. The engines were air-cooled until the introduction of the 996 series in 1998. The 911 has been raced extensively by private and factory teams, in

3276-447: Is about 10 kg (22 lb) lighter than 90 degree crankshaft, but they create a lot of vibration. Such is the strength of a top fuel crankshaft that in one incident, the entire engine block was split open and blown off the car during an engine failure, and the crank, with all eight connecting rods and pistons, was left still bolted to the clutch. Pistons are made of forged aluminum. They have three rings and aluminum buttons retain

3402-452: Is actually more efficient than deflagration, but is usually avoided due to its damaging effects on engine components.) If detonation is allowed to persist under extreme conditions or over many engine cycles, engine parts can be damaged or destroyed. The simplest deleterious effects are typically particle wear caused by moderate knocking, which may further ensue through the engine's oil system and cause wear on other parts before being trapped by

3528-422: Is an engine driven mechanical fuel pump and about 42 fuel nozzles. The pump can flow 100 US gallons (380 L) per minute at 7500 rpm and 500 psi (3,450 kPa) fuel pressure. In general 10 injectors are placed in the injector hat above the supercharger, 16 in the intake manifold and two per cylinder in the cylinder head. Usually a race is started with a leaner mixture, then as the clutch begins to tighten as

3654-447: Is built exclusively of specialized parts. It retains the basic configuration with two valves per cylinder activated by pushrods from a centrally-placed camshaft. The engine has hemispherical combustion chambers , a 58-degree in. to ex. valve stem angle; 4.8 inches (121.92 mm) bore pitch. The block is machined from a piece of forged aluminum. It features press-fitted, ductile iron cylinder liners. There are no water passages in

3780-624: Is disassembled and examined, and worn or damaged components are replaced. Measuring the power output of a top fuel engine directly is not always feasible. Certain models use a torque sensor incorporated as part of the RacePak data system. Dynamometers that can measure the output of a Top Fuel engine exist; however, the main limitation is that a Top Fuel engine cannot be run at its maximum power output for more than 10 seconds without overheating or possibly destroying itself explosively. Making such high power levels from such relatively limited displacement

3906-620: Is driven by gears in the front of the engine. Mechanical roller lifters ( cam followers ) ride atop the cam lobes and drive the steel push rods up into the steel rocker arms that actuate the valves. The rockers are of roller tip type on the intake and exhaust sides. Like the cam follower rollers, the steel tip roller rotates on a steel roller bearing and the steel rocker arms rotate on a pair of through-hardened tool steel shafts within bronze bushings. Intake and exhaust rockers are billet. The dual valve springs are of coaxial type and made out of titanium. Valve retainers are also made of titanium, as are

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4032-437: Is due to the travel of the flame front through the combustible fuel–air mix itself, and due to Rayleigh–Taylor instability (resulting from the hot, low-density combustion gasses expanding into the relatively cold and dense unburnt fuel–air mix) which rapidly stretches the burning zone into a complex of fingers of burning gas that have a much greater surface area than a simple spherical ball of flame would have (this latter process

4158-408: Is enhanced and accelerated by any pre-existing turbulence in the fuel–air mixture). In normal combustion, this flame front moves throughout the fuel/air mixture at a rate characteristic for the particular mixture. Pressure rises smoothly to a peak, as nearly all the available fuel is consumed, then pressure falls as the piston descends. Maximum cylinder pressure is achieved a few crankshaft degrees after

4284-463: Is fitted with a 200 pounds per square inch (1,379 kPa) burst plate . Air is fed to the compressor from throttle butterflies with a maximum area of 65 sq in (41,935 mm). At maximum pressure, it takes approximately 1,000 horsepower (750 kW) to drive the supercharger. These superchargers are in fact derivatives of General Motors scavenging-air blowers for their two-stroke diesel engines , which were adapted for automotive use in

4410-463: Is ignited by two 14 mm (0.55 in) spark plugs per cylinder. These plugs are fired by two 44- ampere magnetos . Normal ignition timing is 58-65 degrees BTDC (This is dramatically greater spark advance than in a petrol engine as "nitro" and alcohol burn far slower). Directly after launch the timing is typically decreased by about 25 degrees for a short time as this gives the tires time to reach their correct shape. The ignition system limits

4536-499: Is in turbocharged Saab H engines , where a system called Automatic Performance Control was used to reduce boost pressure if it caused the engine to knock. Since the avoidance of knocking combustion is so important to development engineers, a variety of simulation technologies have been developed which can identify engine design or operating conditions in which knock might be expected to occur. This then enables engineers to design ways to mitigate knocking combustion whilst maintaining

4662-441: Is less common in cold climates. As an aftermarket solution, a water injection system can be employed to reduce combustion chamber peak temperatures and thus suppress detonation. Steam (water vapor) will suppress knock even though no added cooling is supplied. Turbulence, as stated, has a very important effect on knock. Engines with good turbulence tend to knock less than engines with poor turbulence. Turbulence occurs not only while

4788-456: Is likely to be adopted as a mandated rule for competition. The 54-year history of NHRA has provided hundreds of examples of safety upgrades. In 2000, the NHRA mandated the maximum concentration of nitromethane in a car's fuel be no more than 90%. In the wake of a Gateway International Raceway fatality in 2004, involving racer Darrell Russell , the fuel ratio was reduced to 85%. Complaints from teams in regards to cost, however, has resulted in

4914-469: Is most likely somewhere between 8,500 and 10,000 hp (6,340 and 7,460 kW), which is about twice as powerful as the engines installed on some modern diesel locomotives , with a torque output of approximately 7,400 pound force-feet (10,030  N⋅m ) and a brake mean effective pressure of 1,160–1,450 psi (8–10 MPa). In late 2015, tests using sensors developed by AVL Racing showed peak power of over 11,000 hp (8,200 kW). For

5040-430: Is often a problem when using nitromethane. Because of the relatively slow burn rate of nitromethane, very rich fuel mixtures are often not fully ignited, and some remaining nitromethane can escape from the exhaust pipe and ignite on contact with atmospheric oxygen, burning with a characteristic yellow flame . Additionally, after sufficient fuel has been combusted to consume all available oxygen, nitromethane can combust in

5166-423: Is permanently monitoring the signal of one or more knock sensors (commonly piezoelectric sensor which are able to translate vibrations into an electric signal). If the characteristic pressure peak of a knocking combustion is detected the ignition timing is retarded by steps of a few degrees. If the signal normalizes indicating a controlled combustion the ignition timing is advanced again in the same fashion keeping

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5292-422: Is to attempt to optimize the trade-off between protecting the engine from damaging knock events and maximizing the engine's output torque. Knock events are an independent random process. It is impossible to design knock controllers in a deterministic platform. A single time history simulation or experiment of knock control methods are not able to provide a repeatable measurement of controller's performance because of

5418-443: Is used by Porsche to indicate the revision for production cars, usually on an annual basis. 911s have also been categorized into families based on body styles or engine enhancements: The 911 traces its roots to sketches drawn by Ferdinand "Butzi" Porsche in 1959. The Porsche 911 was developed as a more powerful, larger and a more comfortable replacement for the 356 , the company's first model. The new car made its public debut at

5544-582: The 1963 Frankfurt Motor Show ( German : Internationale Automobil-Ausstellung ). The car was developed with the proof-of-concept twin-fan Type 745 flat-six engine, but the car presented at the auto show had a non-operational mockup of the single-fan 901 engine, receiving a working unit in February 1964. It originally was designated as the "Porsche 901" (901 being its internal project number). A total of 82 cars were built which were badged as 901s. However, French automobile manufacturer Peugeot protested on

5670-643: The Car of the Century , the 911 was fifth. It is one of two in the top five that had remained continuously in production (the original Beetle remained in production until 2003). The one millionth example was manufactured in May 2017 and is in the company's permanent collection. Although Porsche has used internal code numbers for each series of the 911, all models have been marketed and sold as 911s. The model series and associated internal codes are as follows: A series letter

5796-763: The Carrera Panamericana races in Mexico in the 1950s. The RS was developed to meet motorsport homologation requirements. Compared to a standard 911S, the Carrera 2.7 RS had a larger engine (2,687 cc) developing 210 PS (154 kW; 207 hp) with Bosch ( Kugelfischer ) mechanical fuel injection, revised and stiffened suspension, a "ducktail" rear spoiler, larger brakes, wider rear wheels and rear fenders, to fit 185/70VR15 and 215/60VR15 tyres front and rear. In RS Touring form it weighed 1,075 kg (2,370 lb), in Sport Lightweight form it

5922-459: The Porsche 914 for 1973 through 1975 model years. 2,099 units were produced. The 912E was replaced by the front-engine Porsche 924 for the 1977 model year. For the 1976 model year, Porsche introduced the Carrera 3.0 with wide rear flares, optional whaletail, and a variety of other luxury options. It was available in all markets except North America. The Carrera 3.0 was fitted with a variation of

6048-416: The air/fuel mixture in the cylinder does not result from propagation of the flame front ignited by the spark plug , but when one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front. The fuel–air charge is meant to be ignited by the spark plug only, and at a precise point in the piston's stroke. Knock occurs when the peak of the combustion process no longer occurs at

6174-435: The engine displacement to 500 cubic inches (8.19 L). A 4.1875-inch (106.36 mm) bore with a 4.5-inch (114.30 mm) stroke are customary dimensions. Larger bores have been shown to weaken the cylinder block. Compression ratio is about 6.5:1, as is common on engines with overdriven Roots-type superchargers . The engine used to power a Top Fuel drag racing car is based on a second generation Chrysler RB Hemi, but

6300-469: The flame front is subjected to a combination of heat and pressure for a certain duration (beyond the delay period of the fuel used), detonation may occur. Detonation is characterized by an almost instantaneous, explosive ignition of at least one pocket of fuel/air mixture outside of the flame front. A local shockwave is created around each pocket, and the cylinder pressure will rise sharply – and possibly beyond its design limits – causing damage. (Detonation

6426-424: The 1.156 in × 3.300 in (29.36 mm × 83.82 mm) steel wrist pin. The piston is anodized and Teflon coated to prevent galling during the high thrust load operation encountered. The top ring is an L-shaped section "Dykes" ring that provides the best seal during combustion, but a second ring must be used to prevent excessive oil from entering the combustion chamber during intake strokes, as

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6552-640: The 1965 season. In 1971, Don Garlits introduced the Swamp Rat XIV , a rear-engined Top Fuel dragster. While others had been developed in the previous decade, it was the first successful one, winning the 1971 NHRA Winternationals . In 1984, Top Fuel was at a low point. It was having trouble attracting full sixteen-car fields, leading to cutting back to eight-car rosters, while the International Hot Rod Association dropped Top Fuel entirely. The same year, Joe Hrudka offered

6678-535: The 1973 Carrera RS. The Carrera 2.7 model produced for the North American markets, often referred to as the Carrera 2.7 CIS, was powered by the same 2.7-litre engine as the 911S which produced 175 PS (129 kW; 173 hp). The initial Carrera 2.7 models had the same welded-on rear RS flares, before switching to the SC stamped style rear flares during the middle of the 1974 production year. The Carrera 2.7 coupés weighed in at 1,075 kg (2,370 lb),

6804-471: The 3.0 engine and a flat "whale tail" in place of the ducktail spoiler along with wide body panels and large tyres. In 1974, Porsche developed the Carrera RS 3.0 with mechanical fuel injection rated at 230 PS (169 kW; 227 hp). Its price was almost twice that of the 2.7 RS, but it offered racing capability. The chassis was largely similar to that of the 1973 Carrera RSR and the braking system

6930-399: The 911 bodywork with Type 901 four-speed manual transmission (a 5-speed manual transmission was optional). In 1966, Porsche introduced the more powerful 911S with Type 901/02 engine having a power output of 160 PS (118 kW; 158 hp). Forged aluminium alloy wheels from Fuchsfelge , with a 5-spoke design, were offered for the first time. In motorsport at the same time, the engine

7056-404: The 911 had a rear-mounted 130 hp (97 kW) Type 901/01 flat-6 engine, in the " boxer " configuration like the 356, the engine is air-cooled and displaces 1,991 cc (2.0 L) as compared to the 356's four-cylinder, 1,582 cc (1.6 L) unit. The car had four seats although the rear seats were small, thus it is usually called a 2+2 rather than a four-seater (the 356 was also

7182-498: The 911 remained so strong, however, that Porsche revised its strategy and decided to inject new life into the 911 editions. 911 SC sales totaled 58,914 cars. Peter W. Schutz (CEO Porsche AG 1981–1987) wrote: The decision to keep the 911 in the product line occurred one afternoon in the office of Dr. Helmuth Bott  [ de ] , the Porsche operating board member responsible for all engineering and development. I noticed

7308-411: The 911 to meet legislative requirements around the world for both impact safety and emissions. First, the engine size was increased to 2,687 cc achieving higher torque. Second, new impact bumpers conformed with low-speed protection requirements of US regulations. Thirdly, the use of K-Jetronic CIS Bosch fuel injection in two of the three models in the line up— the 911 and 911S models, retaining

7434-470: The 911. The name "Targa" came from the Targa Florio sports car road race in Sicily , Italy in which Porsche had several victories until 1973. The last win in the subsequently discontinued event was scored with a 911 Carrera RS against prototypes entered by Ferrari and Alfa Romeo . The road-going Targa was equipped with a removable roof panel and a removable plastic rear window (although a fixed glass version

7560-406: The 911L model with 911E with fuel injection. It remained in production until July 1969. The 911E gained wider tires on 6J-15 wheels. The C series was introduced in August 1969 with an enlarged 2.2-litre engine (84 mm bore x 66 mm stroke). The wheelbase for all 911 and 912 models was increased from 2,211–2,268 mm (87.0–89.3 in), to help as a remedy to the car's nervous handling at

7686-539: The 911S's Type 911/02 (180 PS (132 kW; 178 hp) at 6,500 rpm), but 911E was quicker in acceleration up to 160 km/h (99 mph). The E series for 1972–1973 model years (August 1971 to July 1972 production) consisted of the same models, but with a new, larger 2,341 cc (2.3 L) engine. This is known as the "2.4 L" engine, despite its displacement being closer to 2.3 litres. The 911E (Type 911/52 engine) and 911S (Type 911/53) used Bosch mechanical fuel injection (MFI) in all markets. For 1972

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7812-459: The 911T (Type 911/57) was carbureted , except in the US and some Asian markets where the 911T also came with (MFI) mechanical fuel injection (Type 911/51 engine) with power increase over European models (130 hp) to 140 hp commonly known as a 911T/E. With power and torque increase, the 2.4-litre cars also got a newer, stronger transmission, identified by its Porsche type number 915. Derived from

7938-603: The 930 Turbo's 2994 cc engine (minus the turbocharger ). The engine (dubbed the 930/02) featured K-Jetronic CIS. It developed 200 PS (147 kW; 197 hp) in contrast to the older Carrera 2.7 MFI model's 210 PS (154 kW; 207 hp). The crankcase and gearbox housing were made of aluminium rather than magnesium for improved reliability. Magnesium cases were reviled for thermal expansion/contraction issues as engines grew in displacement and heat generation also increased. The new engine, which featured bigger intake and exhaust valves, produced greater torque allowing

8064-611: The Belgian Gendarmerie. The 1976 Carrera 2.7 MFI Sondermodells were the last mechanically fuel injected 911 produced by Porsche and still featured the 1973 RS engine. For the 1976 model year, the 912E was produced for the U.S. market. This was a 4-cylinder version of the 911 in the same manner as the 912 that had last been produced in 1969. It used the I-series chassis powered by the Volkswagen 2.0 engine also used in

8190-466: The Carrera 3.0 to achieve the same performance as the previous Carrera 2.7, 0–100 km/h (0–62 mph) in 6.1 seconds and 0–200 km/h (0–124 mph) in 27 seconds. Both versions boasted a top speed of approximately 236 km/h (147 mph). Weight increased marginally by 45 kg (99 lb) to 1,120 kg (2,470 lb). The 911 Carrera 3.0 was produced in both targa (1,125 examples produced) and coupé (2,566) versions. The Carrera 3.0

8316-496: The Dykes-style ring offers less than optimal reverse gas/oil sealing. The third ring is an oil scraper ring whose function is to scrape the majority of the oil film off the cylinder wall as the piston descends from top dead center (TDC), to prevent oil being exposed to combustion heat and contaminating the upcoming round of fuel/air. This "oil scraping" also provides a key heat removal step for the cylinder walls and piston skirts,

8442-557: The Porsche 754 T7. Erwin Komenda , the leader of the Porsche car body construction department who initially objected, was also involved later in the design. Production of the 356 ended in 1965, but there was still a market for a 4-cylinder car, particularly in the US. The 912 , introduced in the same year, served as a direct replacement, offering the de-tuned version of 356 SC's 4-cylinder, 1,582 cc (1.6 L), 90 hp (67 kW; 91 PS) boxer four Type 616/36 engine inside

8568-455: The Top Fuel category is also the most associated female in the drag racing world, Shirley Muldowney , who won three championships during her career. Since 2015, NHRA regulations limit the composition of the fuel to a maximum of 90% nitromethane ; the remainder is largely methanol . However, this mixture is not mandatory, and less nitromethane may be used if desired. While nitromethane has

8694-569: The US market). New inlet manifold and exhaust systems were fitted. The 915 transmission was carried over from the SC series for the first three model years. In 1987, the Carrera got a new five-speed gearbox sourced from Getrag , model number G50 with proven BorgWarner synchronizers. This slightly heavier version also featured a hydraulically operated clutch. Engine knocking#Pre-ignition In spark-ignition internal combustion engines , knocking (also knock , detonation , spark knock , pinging or pinking ) occurs when combustion of some of

8820-492: The absence of atmospheric oxygen, producing hydrogen , which can often be seen burning from the exhaust pipes at night as a bright white flame. In a typical run the engine can consume between 12 US gallons (45.42 L) and 22.75 US gallons (86.12 L) of fuel during warmup, burnout, staging, and the quarter-mile run. Like many other motor sport formulas originating in the United States, NHRA -sanctioned drag racing favors heavy restrictions on engine configuration, sometimes to

8946-499: The back-half of the roll-cage to prevent any debris from entering the cockpit. This also was the result of the fatal crash at Gateway International Raceway. The rear tire pressure is also heavily regulated by Goodyear Tire and Rubber on behalf of the NHRA, at 7 psi (48 kPa), the absolute minimum pressure allowed. At present, final drive ratios higher than 3.20 (3.2 engine rotations to one rear axle rotation) are prohibited, in an effort to limit top speed potential, thus reducing

9072-419: The big end while the pin runs directly in the rod. The supercharger must be a 14-71 type Roots blower . It has twisted lobes and is driven by a toothed belt . The supercharger is slightly offset to the rear to provide an even distribution of air. Absolute manifold pressure is usually 56–66 pounds per square inch (386–455 kPa), but up to 74 pounds per square inch (510 kPa) is possible. The manifold

9198-616: The block, which adds considerable strength and stiffness. The engine is cooled by the incoming air/fuel mixture and the lubricating oil. Like the original Hemi, the racing cylinder block has a deep skirt for strength. There are five main bearing caps, which are fastened with aircraft-standard-rated steel studs, with additional reinforcing main studs and side bolts (" cross-bolting "). There are three approved suppliers of these custom blocks; Keith Black , Brad Anderson, and Alan Johnson. The cylinder heads are machined from aluminum billets . As such, they, too, lack water jackets and rely entirely on

9324-419: The car was simply called the Porsche 911 Turbo worldwide. The larger engine helped reduce some of the turbo lag inherent in the earlier models. In 1989, a 5-speed manual transmission became available for the 930. The 930 was replaced in 1990 with the 964 turbo featuring the same 3.3-litre engine. There have been turbocharged variants of each subsequent generation of 911 since then. In 1978, Porsche introduced

9450-416: The car well into the 1980s until the FIA and IMSA rules were changed. For the 1978 model year, Porsche revised the 930 with a larger 3.3-litre turbocharged engine with intercooler rated at 300 PS (221 kW; 296 hp). To fit the intercooler a newly designed "tea-tray" tail spoiler replaced the earlier whale tail spoiler. Porsche dropped the "Carrera" nomenclature for the North American markets and

9576-434: The centre of gravity slightly forward for better handling. An extra oil filler/inspection flap was located on the rear wing, for this reason it became known as an "Oil Klapper", "Ölklappe" or "Vierte Tür (4th door)". The F series (August 1972 to July 1973 production) moved the oil tank back to the original behind-the-wheel location. This change was in response to complaints that gas-station attendants often filled gasoline into

9702-403: The combustion process to develop peak pressure at the ideal time for maximum recovery of work from the expanding gases. The spark across the spark plug's electrodes forms a small kernel of flame approximately the size of the spark plug gap. As it grows in size, its heat output increases, which allows it to grow at an accelerating rate, expanding rapidly through the combustion chamber. This growth

9828-459: The detriment of technological development. In some cases, teams are required to use technologies that may be decades old, resulting in cars that may seem substantially less advanced than the average family car. However, while some basic facets of engine configuration are heavily restricted, other technologies, such as fuel injection , clutch operation, ignition, and car materials and design, are under constant development. NHRA competition rules limit

9954-484: The duration of the race and with a peak of over 5.6  g 0 (55  m/s ). Because of the speeds, this class races a 1,000 foot (304.8 m) distance, not the traditional drag-race length of one-fourth of a statute mile, or 1,320 feet (402.3 m). The rule was introduced in 2008 by the National Hot Rod Association after the fatal crash of Funny Car driver Scott Kalitta during

10080-415: The early days of the sport. The model name of these superchargers delineates their size – the once commonly used 6-71 and 4-71 blowers were designed for General Motors diesels having six cylinders of 71 cu in (1.16 L) each, and four cylinders of 71 cu in (1.16 L) each, respectively. Thus, the currently used 14-71 design can be seen to be a huge increase in power delivery over

10206-475: The early designs, purpose-built for the GM Detroit Diesel truck powerplants. Mandatory safety rules require a secured Kevlar-style blanket over the supercharger assembly as "blower explosions" are not uncommon, from the volatile air/fuel mixture coming from the fuel injectors being drawn directly through them. The absence of a protective blanket exposes the driver, team and spectators to shrapnel in

10332-416: The end of a run. During a nighttime event, the slow-burning nitromethane can be seen to extend flames many feet out from the exhaust pipes. The engine is warmed up for about 80 seconds. After the warm up the valve covers are taken off, oil is changed and the car is refueled. The run including tire warming is about 100 seconds which results in a "lap" of about three minutes. After each lap, the entire engine

10458-439: The engine at its best possible operating point - the so-called ″knock limit″. Modern knock control-loop systems are able to adjust ignition timings for every cylinder individually. Depending on the specific engine the boost pressure is regulated simultaneously. This way performance is kept at its optimum while mostly eliminating the risk of engine damage caused by knock (e.g. when running on low octane fuel). An early example of this

10584-435: The engine is inhaling but also when the mixture is compressed and burned. Many pistons are designed to use "squish" turbulence to violently mix the air and fuel together as they are ignited and burned, which reduces knock greatly by speeding up burning and cooling the unburnt mixture. One example of this is all modern side valve or flathead engines . A considerable portion of the head space is made to come in close proximity to

10710-454: The engine speed builds, the air/fuel mixture is enriched. As the increased engine speed builds up pump pressure, the mixture is made leaner to maintain a predetermined ratio that is based on many factors, especially race track surface friction. The stoichiometry of both methanol and nitromethane is considerably greater than that of racing gasoline, as they have oxygen atoms attached to their carbon chains and gasoline does not. This means that

10836-405: The engine speed to 8400 rpm. The ignition system provides initial 60,000 volts and 1.2 amperes. The long duration spark (up to 26 degrees) provides energy of 950 millijoules (0.23 cal th ). The plugs are placed in such a way that they are cooled by the incoming charge. The ignition system is not allowed to respond to real time information (no computer-based spark lead adjustments), so instead

10962-442: The engine's combustion chambers and cooling system as well as controlling the initial air intake temperature. The addition of tetraethyl lead (TEL), a soluble organolead compound added to gasoline, was common until it was discontinued for reasons of toxic pollution. Lead dust added to the intake charge will also reduce knock with various hydrocarbon fuels. Manganese compounds are also used to reduce knock with petrol fuel. Knock

11088-444: The entrance of a Top Fuel event. Dragsters are limited to a wheelbase of 300 inches (7.6 m). The most prolific active driver in Top Fuel is Tony Schumacher and the most successful crew chief is Alan Johnson, who was the crew chief for six of Schumacher's championships, the back-to-back titles won by driver Gary Scelzi and was the crew chief for his brother Blaine for his entire professional career. The first female driver in

11214-424: The event of a blown rod. Teams are fined and points are lost if oil is spilled on the track surface, so all teams make provision for absorbent blankets/diapers below the engine. Oil pump pressure is somewhere around 160–170 psi (1,100–1,170 kPa) during the run, 200 psi (1,380 kPa) at start up, but actual figures differ between teams. Fuel is injected by a constant flow injection system. There

11340-404: The event that nearly any irregularity in the induction of the air/fuel mixture, the conversion of combustion into rotating crankshaft movements, or in the exhausting of spent gasses is encountered. The oil system has a wet sump which contains 16 US quarts (15.1 L) of SAE 70 mineral or synthetic racing oil. The pan is made of titanium or aluminum. Titanium can be used to prevent oil spills in

11466-603: The first U.S. Fuel and Gas Championship at Famoso Raceway in March 1959. Bob Hansen won Top Fuel Eliminator (TFE) in his A/HR, with a speed of 136 mph (218.9 km/h). Jimmy Nix , who previously ran a Top Gas dragster; Jim Johnson , who ran a Dodge Polara stocker , and who had won the B/SA title in 1963; Jim Nelson ; and Dode Martin pioneered TF/FC. (Nix tried to persuade Chrisman to get Mercury Racing Director Fran Hernandez to allow him to run his Comet's 427 on nitro, as

11592-481: The gasoline engine the fuel is slowly oxidizing all the time while it is being compressed before the spark. This allows for changes to occur in the structure/makeup of the molecules before the very critical period of high temperature/pressure. Due to the large variation in fuel quality, atmospheric pressure and ambient temperature as well as the possibility of a malfunction, every modern combustion engine contains mechanisms to detect and prevent knocking. A control loop

11718-456: The grounds that in France it had exclusive rights to car names formed by three numbers with a zero in the middle. Instead of selling the new model with a different name in France, Porsche changed the name to 911. Internally, the cars' part numbers carried on the prefix 901 for years. Production began in September 1964, with the first 911s exported to the US in February 1965. The first models of

11844-402: The incoming air/fuel mixture and lubricating oil for their cooling. The original Chrysler design of two large valves per cylinder is used. The intake valve is made from solid titanium and the exhaust from solid Nimonic 80A or similar. Seats are of ductile iron . Beryllium-copper has been tried but its use is limited due to its toxicity. Valve sizes are around 2.45 in (62.23 mm) for

11970-414: The injector pump, fuel injector, combustion chamber, piston crown and cylinder head can reduce knocking greatly, and modern engines using electronic common rail injection have very low levels of knock. Engines using indirect injection generally have lower levels of knock than direct injection engines, due to the greater dispersal of oxygen in the combustion chamber and lower injection pressures providing

12096-450: The intake and 1.925 in (48.90 mm) for the exhaust. In the ports there are integral tubes for the push rods. The heads are sealed to the block by copper gaskets and stainless steel o-rings . Securing the heads to the block is done with aircraft-rated steel studs and stud nuts. The camshaft is billet steel, made from 8620 carbon or S7 through-hardened tool steel or similar. It runs in five oil pressure lubricated bearing shells and

12222-431: The introduction of the whale tail rear spoiler, available as an option on the 1974-75 Carrera 2.7 models, as well as the newly introduced 930 Turbo. The Carrera 2.7 was replaced by the Carrera 3.0 for the 1976 model year, except for a special run of 113 1976 Carrera 2.7 MFI coupés were built for the German market featuring the 911/83 RS engine, with an additional 20 narrow-bodied 1976 Carrera MFI 2.7 Targas being supplied to

12348-498: The level of danger. In 1958, NHRA banned nitro in all categories; the American Hot Rod Association (AHRA) still allowed it, and Fuel Dragsters (FD), Hot Roadsters (HR), and Fuel Coupés (FC): this led to Fuel Altereds (AA/FAs), Factory Experimentals (A/FXs), and (ultimately) Funny Cars (TF/FCs). Independent drag strips, not NHRA sanctioned, offered venues for the fuel racers. Smokers Car Club hosted

12474-415: The limit. The overall length of the car did not change, but the rear wheels were relocated further back. Fuel injection arrived for the 911S (901/10 engine) and for a new middle model, 911E (901/09 engine). The D series was produced from Aug. 1970 to July 1971. The 2.2-litre 911E (C and D series) had lower power output of the 911/01 engine (155 PS (114 kW; 153 hp) at 6,200 rpm) compared to

12600-421: The narrow rear arches of the old 2.4, now had a 2.7-litre engine rated at 150 PS (110 kW; 148 hp) and 175 PS (129 kW; 173 hp), respectively. The standard 911 version received an increase to 165 PS (121 kW; 163 hp) for Model Year 1976, which meant that starting from MY 1976, there was only a difference in power of 10 hp between the 911 and the 911S. The engine remained

12726-448: The new version of the 911, called the '911SC'. Porsche reintroduced the SC designation for the first time since the 356SC (as distinguished from the race engined 356 Carrera). There was no Carrera version of the 911SC. According to modern-day Porsche literature and websites (there is no period reference to SC meaning anything) the "SC" stands for "Super Carrera". It featured a 3.0-litre aluminium engine with Bosch K-Jetronic fuel injection and

12852-440: The oil film is renewed as the piston moves upward after reaching bottom dead center (BDC). The connecting rods are of forged aluminum and do provide some shock damping, which is why aluminum is used in place of titanium, because titanium connecting rods transmit too much of the combustion impulse to the big-end rod bearings, endangering the bearings and thus the crankshaft and block. Each con rod has two bolts, shell bearings for

12978-455: The oil filter. Such wear gives the appearance of erosion, abrasion, or a "sandblasted" look, similar to the damage caused by hydraulic cavitation . Severe knocking can lead to catastrophic failure in the form of physical holes melted and pushed through the piston or cylinder head (i.e. rupture of the combustion chamber ), either of which depressurizes the affected cylinder and introduces large metal fragments, fuel, and combustion products into

13104-452: The oil system. Hypereutectic pistons are known to break easily from such shock waves. Detonation can be prevented by any or all of the following techniques: Because pressure and temperature are strongly linked, knock can also be attenuated by controlling peak combustion chamber temperatures by compression ratio reduction, exhaust gas recirculation , appropriate calibration of the engine's ignition timing schedule, and careful design of

13230-583: The oil tank. In January 1973, US 911Ts were switched to the new K-Jetronic CIS (Continuous Fuel Injection) system from Bosch on Type 911/91 engine. 911S models also gained a small spoiler under the front bumper to improve high-speed stability. The cars weighed 1,050 kg (2,310 lb). The 911 ST was produced in small numbers for racing (the production run for the ST lasted from 1970 to 1971). The cars were available with engines of either 1,987 cc (2.0 L) or 2,404 cc (2.4 L) displacement, having

13356-408: The optimum moment for the four-stroke cycle . The shock wave creates the characteristic metallic "pinging" sound, and cylinder pressure increases dramatically. Effects of engine knocking range from inconsequential to completely destructive. Knocking should not be confused with pre-ignition —they are two separate events. However, pre-ignition can be followed by knocking. The phenomenon of detonation

13482-413: The piston crown, making for much turbulence near TDC. In the early days of side valve heads this was not done and a much lower compression ratio had to be used for any given fuel. Also such engines were sensitive to ignition advance and had less power. Knocking is more or less unavoidable in diesel engines , where fuel is injected into highly compressed air towards the end of the compression stroke. There

13608-409: The piston passes TDC, so that the force applied on the piston (from the increasing pressure applied to the top surface of the piston) can give its hardest push precisely when the piston's speed and mechanical advantage on the crank shaft gives the best recovery of force from the expanding gases, thus maximizing torque transferred to the crankshaft. When unburned fuel–air mixture beyond the boundary of

13734-596: The previously standard gasoline-burning heater became optional. The Targa (meaning "plate" in Italian ) version was introduced. The Targa had a stainless steel -clad roll bar, as automakers believed that proposed rollover safety requirements by the US National Highway Traffic Safety Administration (NHTSA) would make it difficult for fully open convertibles to meet regulations for sale in the US, an important market for

13860-512: The purposes of comparison, a 2009 SSC Ultimate Aero TT , which at the time was among the world's most powerful production automobiles, produces 1,287 hp (960 kW) of power and 1,112 lbf⋅ft (1,508 N⋅m) of torque. From start to finish the engine will turn 240 revolutions. Including start up, burnout, staging and the race, the engine must survive just 500 revolutions before being rebuilt. This calculation assumes an average racing engine speed of roughly 3,800 revolutions per minute over

13986-522: The racing version called the Porsche 934 of 1976 participating at the 24 Hours of Le Mans and other races including battles with the BMW 3.0 CSL "Batmobile" . The FIA Group 5 version called Porsche 935 evolved from the 934. Fitted with a slope nose or "slant nose", the 500+ PS car was campaigned in 1976 by the factory, winning the world championship title. Private teams went on to win many races, like Le Mans in 1979, and continued to compete successfully with

14112-440: The rear wheels produces much more, peaking at around 12,000 pounds-force (53.4 kN) when the car reaches about 330 mph (531.1 km/h). The engine of a Top Fuel dragster generates around 150 dB of sound at full throttle, enough to cause physical pain or even permanent damage. Before a run, race announcers usually advise spectators to cover or plug their ears. Ear plugs and even earmuffs are often handed out to fans at

14238-477: The rocker covers. Billet steel crankshafts are used; they all have a cross plane a.k.a. 90 degree configuration and run in five conventional bearing shells. 180 degree crankshafts have been tried. Due to ease of laying out an exhaust system with even pulsation, the 180 degree crankshaft can offer increased power in engines with interacting exhaust. However this does not concern Top Fuel engines with separate exhaust pipes for each cylinder. A 180 degree crankshaft

14364-426: The rule being rescinded starting in 2008, when the fuel mixture returns to 90%, as NHRA team owners, crew chiefs, and suppliers complained about mechanical failures that can result in oildowns or more severe crashes caused by the reduced nitromethane mixture. They also mandated enclosed roll cages. The NHRA also mandated that different rear tires be used to reduce failure, and that a titanium "shield" be attached around

14490-482: The same weight as the 1973 Carrera RS Touring. For the 1974 model year, the Carrera 2.7 was available with the "ducktail" rear spoiler first introduced with the 1973 Carrera RS. In the North American markets, the ducktail was standard equipment for the Carrera. All other markets the ducktail was optional, except for the home German market where the ducktail had been outlawed by the TÜV road homologation department. This led to

14616-725: The stoichiometric ratio of petrol is 14.7:1 air to petrol, and 1.7:1 air to nitromethane, which, unlike gasoline, already has oxygen in its molecular composition. For a given amount of air consumed, this means that an engine can burn 7.6 times more nitromethane than gasoline. Nitromethane also has a high latent heat of vaporization , meaning that it will absorb substantial engine heat as it vaporizes, providing an invaluable cooling mechanism. The laminar flame speed and combustion temperature are higher than gasoline's at 0.5 m/s (1.6 ft/s) and 2,400 °C (4,350 °F) respectively. Power output can be increased by using very rich air-fuel mixtures. This also helps prevent pre-ignition , which

14742-450: The superchargers and clutch assemblies to contain broken parts in the event of failure or explosion; damage resistant fuel tank, lines, and fittings; externally accessible fuel and ignition shut-offs (built to be accessible to rescue staff); braking parachutes; and a host of other equipment, all built to the very highest standards of manufacturing. Any breakthrough or invention that is likely to contribute to driver, staff, and spectator safety

14868-405: The transmission in the 908 race car, the 915 did away with the 901 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. The E series had the unusual oil filler behind the right side door, with the dry sump oil tank relocated from behind the right rear wheel to the front of it in an attempt to move

14994-401: The wide 205/50R15 & 225/50R15 Pirelli P7 tyres, and a large rear spoiler often known as a " whale tail " on the early cars (modified from the original 1974 IROC design). They were initially fitted with a 3.0-litre engine producing 260 PS (191 kW; 256 hp), and a four-speed manual transmission. Production of the first 400 units qualified the 930 for FIA Group 4 competition. With

15120-572: Was about 100 kg (220 lb) lighter, the saving coming from thin gauge steel used for parts of the body shell and also the use of thinner glass. In total, 1,580 units were made, and qualified for the FIA Group 4 class. 49 Carrera RSR cars were built with 2,808 cc (2.8 L) engines rated at 300 PS (221 kW; 296 hp). For the 1974 IROC Championship (which started in December 1973), 1973 Carrera RSR models were fitted with

15246-661: Was available with a manual gearbox (type 915) with 4 or 5 speeds as well as 3-speed automatic transmission (called the Sportomatic). Production totals were 3,691 manual cars and 58 Sportomatic cars. For the 1975 model year, Porsche introduced the first production turbocharged 911. Although called the 930 Turbo (930 being its internal type number) in Europe, it was marketed as the 930 Turbo Carrera in North America. The body shape incorporated wide wheel-arches to accommodate

15372-483: Was described in November 1914 in a letter from Lodge Brothers (spark plug manufacturers, and sons of Sir Oliver Lodge ) settling a discussion regarding the cause of "knocking" or "pinging" in motorcycles. In the letter they stated that an early ignition can give rise to the gas detonating instead of the usual expansion, and the sound that is produced by the detonation is the same as if the metal parts had been tapped with

15498-518: Was developed into the Type 901/20 and was installed in the mid-engine 904 and 906 with an increased power output of 210 PS (154 kW; 207 hp), as well as fuel injected Type 901/21 installed in later variants of the 906 and 910 with a power output of 220 PS (162 kW; 217 hp). In August 1967, the A series went into production with dual brake circuits and widened (5.5J-15) wheels still fitted with Pirelli Cinturato tyres, and

15624-446: Was dropped in the production version. The first 911 Cabriolet debuted in late 1982, as a 1983 model. This was Porsche's first cabriolet since the 356 of the mid-1960s. A total of 4,214 were sold in its introductory year, despite its premium price relative to the open-top targa. Cabriolet versions of the 911 have been offered ever since. In 1979, Porsche had made plans to replace the 911 with their new 928 company flagship . Sales of

15750-453: Was from the 917 racing car. The use of thinner metal plate panels and a minimalist interior enabled its weight to be reduced to around 900 kg (2,000 lb). The Carrera RSR 3.0 was sold to racing teams and scored wins in several major sports car races of the mid-1970s. Also, a prototype Carrera RSR Turbo (with 2.1-litre engine due to a 1.4x equivalency formula) came second at the 24 Hours of Le Mans in 1974 and won several major races,

15876-457: Was offered from 1968). The 110 PS (81 kW; 110 hp) 911T was also launched in 1967 with Type 901/03 engine. The 130 PS (96 kW; 128 hp) model was renamed the 911L with Type 901/06 engine and ventilated front disc brakes. The brakes had been introduced on the previous 911S. The 911R with 901/22 engine had a limited production (20 in all), as this was a lightweight racing version with thin fiberglass reinforced plastic doors,

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