The BMW M20 is a SOHC straight-six petrol engine which was produced from 1977 to 1993. It was introduced eight years after the larger BMW M30 straight-six engine, which remained in production alongside the M20.
100-745: The first cars to use the M20 were the E12 5 Series and the E21 3 Series . The initial M20 model had a displacement of 2.0 L (122 cu in), with later versions having displacements of up to 2.7 L (165 cu in). The M20 began to be phased out following the introduction of the M50 engine in 1990. The final M20 engines were fitted to the E30 3 Series wagon (estate) and convertible model built in April 1993. The M20
200-560: A Fiat 132 , was made. Also in 1971, Paul Bracq had finalised the E12's design, however, compared with the later series production E12, Bracq's design car had a more stretched, and dynamic appearance. Computers were used in BMW development for the first time to calculate front and rear crumple zones ; the roof was designed with a rollover protection structure . The body has a drag coefficient of 0.44. BMW had previously located turn signal stalks on
300-589: A V8 engine produced from 1992 to 1996 . As per the M30, the M20 has an iron block, aluminium head and a SOHC valvetrain with 2 valves per cylinder. It has a traditional rocker arm design and no hydraulic tappets. The major differences to the M30 are: The first models to use the M20 were the E12 520/6 and the E21 320/6, which used a 1,991 cc (121 cu in) version known as the M20B20VE or M60/2 . This engine uses
400-590: A bore of 80 mm (3.15 in) and a stroke of 66 mm (2.60 in). A Solex 4A1 four-barrel carburetor was used in the M20B20VE ("VE" is for vergaser - "carburettor" in German), and it has a compression ratio of 9.2:1 and a redline of 6,400 rpm. The M20 first became fuel-injected in 1981, with Bosch K-Jetronic used in a 92 kW (123 hp) version called the M20B20KE . The compression ratio
500-585: A computerized closed-loop feedback fuel injection system using one or more oxygen sensors (also known as Lambda Sonds or sensors). Other variants combined three-way converters with carburetors equipped with feedback mixture control were used. An unregulated three-way converter features the same chemical processes but without the oxygen sensor, which meant higher NO x emissions, particularly under partial loads. These were low-cost solutions, typically used for retrofitting to older cars or for smaller, cheaper cars. Three-way converters are effective when
600-515: A reagent such as ammonia to reduce the NO x into nitrogen and water. Ammonia is supplied to the catalyst system by the injection of urea into the exhaust, which then undergoes thermal decomposition and hydrolysis into ammonia. The urea solution is also referred to as diesel exhaust fluid (DEF). Diesel exhaust contains relatively high levels of particulate matter. Catalytic converters remove only 20–40% of PM so particulates are cleaned up by
700-519: A redox reaction . Catalytic converters are usually used with internal combustion engines fueled by gasoline or diesel , including lean-burn engines, and sometimes on kerosene heaters and stoves. The first widespread introduction of catalytic converters was in the United States automobile market. To comply with the U.S. Environmental Protection Agency 's stricter regulation of exhaust emissions, most gasoline-powered vehicles starting with
800-482: A 2-litre version rather than a 2.3 litre version. Originally, four-cylinder cars have a bonnet with a sunken central portion whereas on six-cylinder cars this section is raised. The leading edge of the bonnet was flat. After the August 1976 facelift all models featured the same bonnet, with a narrow raised central section reaching all the way forward and wrapping around the "kidneys". M30-engined cars can be identified by
900-484: A 90 kW 2.0-litre Solex 4A1 carburetted version, and as a 105 kW 2.3-litre K-Jetronic multi-point injected version. Later versions had displacements up to 2.7 L (165 cu in). The M20 was used in the E12 5 Series , E21 3 Series , E28 5 Series , E30 3 Series and E34 5 Series . Early versions of the M20 were sometimes referred to as the "M60", although the M60 designation has since been re-used for
1000-588: A carburettor or fuel-injection. A year after launch, the first model powered by a straight-six engine was introduced. By the final years of E12 production, most models used a straight-six engine. There was no M5 model for the E12, however the E12 M535i is considered to be the predecessor to the M5. The E24 6 Series coupés were built on the E12 platform up until 1982. The E12 was replaced by the E28 5 Series in 1981, although
1100-420: A catalytic combustor for gas turbines in the early 1970s, allowing combustion without significant formation of nitrogen oxides and carbon monoxide. Four-way catalytic converters have also been developed which also remove particulates from engine exhaust; since most of these particulates are unburned hydrocarbons, they can be burned to convert them into carbon dioxide. The catalytic converter's construction
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#17327831644421200-454: A catalytic converter for any reason other than its direct and immediate replacement. Nevertheless, some vehicle owners remove or "gut" the catalytic converter on their vehicle. In such cases, the converter may be replaced by a welded-in section of ordinary pipe or a flanged "test pipe", ostensibly meant to check if the converter is clogged by comparing how the engine runs with and without the converter. This facilitates temporary reinstallation of
1300-593: A catalytic converter was patented by Eugene Houdry , a French mechanical engineer. Houdry was an expert in catalytic oil refining, having invented the catalytic cracking process that all modern refining is based on today. Houdry moved to the United States in 1930 to live near the refineries in the Philadelphia area and develop his catalytic refining process. When the results of early studies of smog in Los Angeles were published, Houdry became concerned about
1400-408: A common housing; however, in some instances, they may be housed separately. A three-way catalytic converter does three simultaneous tasks: Reduction of nitrogen oxides to nitrogen (N 2 ) Oxidation of carbon, hydrocarbons, and carbon monoxide to carbon dioxide These three reactions occur most efficiently when the catalytic converter receives exhaust from an engine running slightly above
1500-461: A compression ratio of 9.4:1, a redline of 6,500 rpm and uses Bosch Motronic 1.1 engine management. In 1987, a catalyzed model with Motronic 1.3 engine management was introduced. The compression ratio was reduced to 8.8:1 but thanks to the more sophisticated electronics power remained nearly as before, at 125 kW (170 PS; 168 hp). The uncatalyzed engine was kept in production for Southern Europe and other markets where unleaded petrol
1600-475: A head gasket leak, can also cause high unburned hydrocarbons. Emissions regulations vary considerably from jurisdiction to jurisdiction. Most automobile spark-ignition engines in North America have been fitted with catalytic converters since 1975, and the technology used in non-automotive applications is generally based on automotive technology. In many jurisdictions, it is illegal to remove or disable
1700-496: A limit of phosphorus concentration in engine oils was adopted in the API SM and ILSAC GF-4 specifications. Depending on the contaminant, catalyst poisoning can sometimes be reversed by running the engine under a very heavy load for an extended period of time. The increased exhaust temperature can sometimes vaporize or sublimate the contaminant, removing it from the catalytic surface. However, removal of lead deposits in this manner
1800-477: A power output of 125 PS (92 kW) or more have an additional sway bar on the rear axle. All models except the M535i have 14-inch steel alloy wheels with a wheel-width of either 5.5 or 6 inches. Therefore, the tyre size is either 175 mm or 195 mm. All models use worm and sector steering, which is power assisted from the 528 onwards. The braking system is a dual-circuit system with front disc brakes; on
1900-710: A pre-cat, a small catalytic converter upstream of the main catalytic converter which heats up faster on vehicle start up, reducing the emissions associated with cold starts. A pre-cat is most commonly used by an auto manufacturer when trying to attain the Ultra Low Emissions Vehicle (ULEV) rating, such as on the Toyota MR2 Roadster. Catalytic converters have proven to be reliable and effective in reducing noxious tailpipe emissions. However, they also have some shortcomings in use, and also adverse environmental effects in production: Because of
2000-405: A precisely controlled air-fuel mixture that quickly and continually cycles between lean and rich combustion. Oxygen sensors monitor the exhaust oxygen content before and after the catalytic converter, and the engine control unit uses this information to adjust the fuel injection so as to prevent the first ( NO x reduction) catalyst from becoming oxygen-loaded, while simultaneously ensuring
2100-455: A result of Switzerland having adopted the same emissions rules, making it worthwhile to develop such a version. Unique to the Swedish market were a BMW 518i and a BMW 520i, fitted with the identical 2 litre engine, but the BMW 518i receiving poorer equipment. The BMW 520i was fitted with chromed wheel rings and a locking fuel cap. It was also fitted with head restraints in the rear, an armrest in
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#17327831644422200-657: A soot trap or diesel particulate filter (DPF). In the U.S., all on-road light, medium, and heavy-duty diesel-powered vehicles built after 1 January 2007, are subject to diesel particulate emission limits, and so are equipped with a 2-way catalytic converter and a diesel particulate filter. As long as the engine was manufactured before 1 January 2007, the vehicle is not required to have the DPF system. This led to an inventory runup by engine manufacturers in late 2006 so they could continue selling pre-DPF vehicles well into 2007. For lean-burn spark-ignition engines, an oxidation catalyst
2300-520: A sports steering wheel, alloy wheels on lower profile tyres, and optional front and rear spoilers. Later, the similar Motorsport 535i package was available for the 525i/528i model, consisting of the 3.5L engine from the E24 635CSi . The first M-badged 5 Series was the M535i, which began production in 1980. The M535i is powered by the 3.5 L (214 cu in) M90 straight-six engine which produces 160 kW (215 bhp). The sole gearbox choice
2400-534: Is a 5-speed manual and 1,650 M535i cars were produced (including 240 CKD for South Africa). Features include optional front and rear spoilers, optional M-striping, sports suspension, Recaro sport seats, the steering wheel from the BMW M1 , a dogleg close-ratio transmission, a limited-slip differential and larger brakes. The M535i is considered to be the predecessor to the BMW M5 model, which has been produced since
2500-439: Is as follows: Upon failure, a catalytic converter can be recycled into scrap . The precious metals inside the converter, including platinum, palladium, and rhodium, are extracted. Catalytic converters require a temperature of 400 °C (750 °F) to operate effectively. Therefore, they are placed as close to the engine as possible, or one or more smaller catalytic converters (known as "pre-cats") are placed immediately after
2600-462: Is permitted and a rich mixture is commanded to increase power and prevent exhaust gas temperature from exceeding design limits. This presents a challenge for control system and catalyst design. During such operations, large amounts of unburnt HC are produced by the engine, well beyond the capacity of the catalyst to release oxygen. The surface of the catalyst quickly becomes saturated with HC. When returning to lower power output and leaner air–fuel ratios,
2700-407: Is used in the same manner as in a diesel engine. Emissions from lean burn spark ignition engines are very similar to emissions from a diesel compression ignition engine. Many vehicles have a close-coupled catalytic converter located near the engine's exhaust manifold . The converter heats up quickly, due to its exposure to the very hot exhaust gases, allowing it to reduce undesirable emissions during
2800-499: Is usually in response to government regulation, either through environmental regulation or through health and safety regulations. Catalytic converter prototypes were first designed in France at the end of the 19th century, when only a few thousand "oil cars" were on the roads; these prototypes had inert clay-based materials coated with platinum , rhodium , and palladium and sealed into a double metallic cylinder. A few decades later,
2900-404: Is usually not possible because of lead's high boiling point. Any condition that causes abnormally high levels of unburned hydrocarbons (raw or partially burnt fuel or oils) to reach the converter will tend to significantly elevate its temperature bringing the risk of a meltdown of the substrate and resultant catalytic deactivation and severe exhaust restriction. These conditions include failure of
3000-729: The 2000tii and 2002tii until 1975. From 1975, it was fitted with a mechanical continuous Bosch K-Jetronic port injection. The 518i (only sold in Sweden and Japan), 528i, and 530i (only sold in the US and Japan) have a Bosch L-Jetronic port injection. The BMW E12 has a self-supporting body, a longitudinally mounted front engine, and rear-wheel drive. All four wheels are suspended independently. The front wheels have MacPherson struts with coil springs, hydraulic shock absorbers, and transverse control arms. The rear axle has semi-trailing arms with coil springs, and hydraulic shock absorbers. Models with
3100-514: The BMW 3.0S , the Motorsport 530i used the fuel-injected 200 PS (147 kW; 197 hp) engine from the BMW 3.0Si and the Motorsport 533i used the injected 3.2-liter engine from the E24 633CSi . Other modifications were a shorter differential ratio of (3.45:1 for the 530 and 3.25:1 for the 530i), a 25% LSD, vented disc brakes, Bilstein shock absorbers , Scheel or Recaro sports seats,
BMW M20 - Misplaced Pages Continue
3200-617: The European Union and the United Kingdom since January 1, 1993 in order to comply with the Euro 1 emission standards . Faulty catalytic converters as well as undamaged early types of converters can restrict the flow of exhaust, which negatively affects vehicle performance and fuel economy. Modern catalytic converters do not significantly restrict exhaust flow. A 2006 test on a 1999 Honda Civic, for example, showed that removing
3300-484: The U.S. Environmental Protection Agency 's new exhaust emissions regulations, most gasoline-powered vehicles manufactured from 1975 onwards are equipped with catalytic converters. Early catalytic converters were "two-way", combining oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC, chemical compounds in fuel of the form C m H n ) to produce carbon dioxide (CO 2 ) and water (H 2 O). These stringent emission control regulations also resulted in
3400-404: The alternator , wiring or fuel lines, with potentially dangerous consequences. In 2023, bipartisan legislation to combat catalytic converter theft was introduced in the U.S. Senate . The Preventing Auto Recycling Thefts Act (PART Act) would mandate catalytic converters in new vehicles to come with traceable identification numbers. Additionally, the legislation would make catalytic converter theft
3500-510: The stoichiometric point. For gasoline combustion, this ratio is between 14.6 and 14.8 parts air to one part fuel, by weight. The ratio for autogas (or liquefied petroleum gas LPG), natural gas , and ethanol fuels can vary significantly for each, notably so with oxygenated or alcohol based fuels, with E85 requiring approximately 34% more fuel, requiring modified fuel system tuning and components when using those fuels. Engines fitted with regulated 3-way catalytic converters are equipped with
3600-537: The 1.8 L and 2.0 L M10 inline-four engines, as per the previous New Class saloons . The 525, 528, 530, 530i and 533i models were fitted with M30 straight-six engines, as used in the New Six large saloons and E9 coupés. The 520, and 523 (the latter was developed, but never put into series production), use the M20 straight-six engine. The 518 had its fuel supplied by a Solex 32/32 DIDTA carburetor , while
3700-967: The 1975 model year are equipped with catalytic converters. These "two-way" converters combine oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO 2 ) and water (H 2 O). Although two-way converters on gasoline engines were rendered obsolete in 1981 by "three-way" converters that also reduce oxides of nitrogen ( NO x ), they are still used on lean-burn engines to oxidize particulate matter and hydrocarbon emissions (including diesel engines, which typically use lean combustion), as three-way-converters require fuel-rich or stoichiometric combustion to successfully reduce NO x . Although catalytic converters are most commonly applied to exhaust systems in automobiles, they are also used on electrical generators , forklifts , mining equipment, trucks , buses , locomotives , motorcycles , and on ships. They are even used on some wood stoves to control emissions. This
3800-422: The 2.0 litre version but a longer 76.8 mm (3.02 in) stroke crank. The bore is 80 mm (3.15 in) and it has a capacity of 2,316 cc (2.3 L). Fuel injection was K-Jetronic, the compression ratio is 9.5:1, the power output is 105 kW (143 PS; 141 hp) and the redline is 6,400 rpm. The 1982 version used LE-Jetronic, the 731 cylinder head, a compression ratio of 9.8:1 and
3900-520: The 325i. The M20B23 versions were not sold in North America. Applications: In 1985, the M20B25 replaced the M20B23. The M20B25 has a capacity of 2,494 cc (152.2 cu in) and initially produced 126 kW (171 PS; 169 hp) (without a catalytic converter ). It has an upgraded cylinder head (known as "885"), a bore of 84 mm (3.31 in), a stroke of 75 mm (2.95 in),
4000-497: The E28 generation. The Alpina B7 Turbo and B7 S Turbo were based on the E12. In South Africa, the 530 MLE was produced as a homologation special for racing, with 218 cars produced. The engine is a 3.0 L (183 cu in) M30 , producing 132 kW (177 bhp). Significant weight reduction measures were undertaken, included body panels made from aluminium or thinner steel. 1974 1975 1976 facelift With
4100-607: The E30 325iS produced 145 kW (194 hp) and the second revision, often referred to as "Evo2" or on the VIN plate as "HP2" produced 155 kW (208 hp). Applications: BMW 5 Series (E12) The BMW E12 is the first generation of 5 Series executive cars, which was produced from 1972 to 1981 and replaced the saloon models of the BMW New Class range. Initial models were powered by inline-four engines, using either
BMW M20 - Misplaced Pages Continue
4200-522: The Garmisch. Development of the E12-series had begun by the end of the 1960s, when wind tunnel tests were conducted. Eberhard von Kuenheim , then chairman of BMW's supervisory board, hired French designer Paul Bracq in 1970 to work as the E12's Chief of design, with Marcello Gandini of Bertone as co-designers of the exterior. In 1971, a road-legal E12 prototype, which looked similar to
4300-451: The U.S. added catalytic systems to their vehicles to meet federal emissions requirements. Two techniques have been developed for the catalytic reduction of NO x emissions under lean exhaust conditions, selective catalytic reduction (SCR) and the NO x adsorber . Instead of precious metal-containing NO x absorbers, most manufacturers selected base-metal SCR systems that use
4400-512: The US market plastic bumper 325e and 528e 'Super Eta', the cylinder head changed to the "885" version, the compression ratio was reduced to 8.5:1 and the redline increased to 5,200 rpm. Power output increased to 95 kW (127 hp) at 4,800 rpm. In the early 1990s BMW South Africa used components from the Alpina C3 2.7 to produce an E30 specifically for Stannic Group N production car racing. The first iteration of this engine used in
4500-404: The United States was the 530i, which was powered by a fuel-injected straight-six engine. Changes for American-market E12s include lower compression pistons, exhaust gas recirculation , an air pump and modified exhaust manifolds called Thermal Reactors. The North American E12 models had larger bumpers (designed to withstand a 5 mph (8.0 km/h) collision without body damage), which increased
4600-546: The addition of Bosch Motronic engine management, a catalytic converter and a compression ratio of 8.8:1. The M20B20 was not sold in the United States, but was available in the E30 (320i) in Canada. Applications: In March 1978 (six months after the M20 was launched), a fuel-injected and larger displacement version known as the M20B23KE (or M60/5 ) was introduced. This version uses the same head (known as "200") and block as
4700-459: The air pump, which led to the development of the three-way catalytic converter. The two-way catalytic converter also continued to be used on certain, lower-cost cars in some markets such as Europe, where NO x emissions were not universally regulated until the introduction of the Euro 3 emissions standard in 2000. The three-way catalytic converters have the additional advantage of controlling
4800-447: The air–fuel mixture is brought back to slightly rich, at a small penalty in CO and HC oxidation efficiency, and the cycle repeats. Efficiency is improved when this oscillation around the stoichiometric point is small and carefully controlled. Closed-loop control under light to moderate load is accomplished by using one or more oxygen sensors in the exhaust system. When oxygen is detected by
4900-527: The car's body "lurches back annoyingly and messily", in part due to the soft springing and hard damping combination. In comparison to the Jaguar XJ6 and Peugeot 604 , the car was viewed as narrow and cramped in the rear and prone to wind noise. Production of the E12 occurred from June 1972 to 1981, with a total of 699,094 cars produced. Initially, the cars were produced in Munich, West Germany. Following
5000-468: The car. Vehicles fitted with catalytic converters emit most of their total pollution during the first five minutes of engine operation; for example, before the catalytic converter has warmed up sufficiently to be fully effective. In the early 2000s it became common to place the catalyst converter right next to the exhaust manifold, close to the engine, for much quicker warm-up. In 1995, Alpina introduced an electrically heated catalyst. Called "E-KAT", it
5100-598: The carburetted versions. In spite of widespread sanctions , locally built E12s also saw some export, the 520 being sent to Argentina and the 518 De Luxe to Belgium, Iran, and Italy. To keep costs down, BMW chose to continue building the E12 in South Africa after the E28 had been introduced elsewhere, with the body now pressed and manufactured locally. Called the E12/8, this model received the new E28 interior and all fuel injected engines, tuned with fuel economy in mind. At
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#17327831644425200-479: The catalyst at reducing NO x is good, and the production of NO x by the engine decreases. To maintain catalyst efficiency, the air–fuel ratio must stay close to stoichiometric and not remain rich or lean for too long. Closed-loop engine control systems are used for effective operation of three-way catalytic converters because of this continuous rich-lean balance required for effective NO x reduction and HC+CO oxidation. The control system allows
5300-412: The catalyst to release oxygen during slightly rich operating conditions, which oxidizes CO and HC under conditions that also favor the reduction of NOx. Before the stored oxygen is depleted, the control system shifts the air–fuel ratio to become slightly lean, improving HC and CO oxidation while storing additional oxygen in the catalyst material, at a small penalty in NO x reduction efficiency. Then
5400-523: The control system must prevent excessive oxygen from reaching the catalyst too quickly, as this will rapidly burn the HC in the already hot catalyst, potentially exceeding the design temperature limit of the catalyst. Excessive catalyst temperature can prematurely age the catalyst, reducing its efficiency before reaching its design lifetime. Excessive catalyst temperature can also be caused by cylinder misfire, which continuously flows unburnt HC combined with oxygen to
5500-409: The conversion of HC and CO is very efficient due to the available oxygen, oxidizing to H 2 O and CO 2 . Slightly rich of stoichiometric, the production of CO and unburnt HC by the engine starts to increase dramatically, available oxygen decreases, and the efficiency of the catalyst for oxidizing CO and HC decreases significantly, especially as stored oxygen becomes depleted. However, the efficiency of
5600-850: The converter in order to pass an emission test. In the United States, it is a violation of Section 203(a)(3)(A) of the 1990 amended Clean Air Act for a vehicle repair shop to remove a converter from a vehicle, or cause a converter to be removed from a vehicle, except in order to replace it with another converter, and Section 203(a)(3)(B) makes it illegal for any person to sell or to install any part that would bypass, defeat, or render inoperative any emission control system, device, or design element. Vehicles without functioning catalytic converters generally fail emission inspections. The automotive aftermarket supplies high-flow converters for vehicles with upgraded engines, or whose owners prefer an exhaust system with larger-than-stock capacity. xxx Catalytic converters have been mandatory on all new gasoline cars sold in
5700-512: The early 1980s. The first car to use the M20B27 was the US market 528e in 1982. The compression ratio of the U.S. M20B27ME version was 9.0:1, compared with for cars sold elsewhere 11.0:1. In 1985, the M20B27ME.E version was introduced, increasing power output to 95 kW (127 hp) despite a lower compression ratio of 10.3:1. In late 1987, the fuel injection was upgraded to Motronic 1.3 on
5800-605: The emission of nitric oxide (NO) and nitrogen dioxide (NO 2 ) (both together abbreviated with NO x and not to be confused with nitrous oxide (N 2 O) ). NO x are precursors to acid rain and smog . Since 1981, the three-way (oxidation-reduction) catalytic converters have been used in vehicle emission control systems in the United States and Canada; many other countries have also adopted stringent vehicle emission regulations that in effect require three-way converters on gasoline-powered vehicles. The reduction and oxidation catalysts are typically contained in
5900-427: The engine is operated within a narrow band of air–fuel ratios near the stoichiometric point. Total conversion efficiency falls very rapidly when the engine is operated outside of this band. Slightly lean of stoichiometric, the exhaust gases from the engine contain excess oxygen, the production of NO x by the engine increases, and the efficiency of the catalyst at reducing NO x falls off rapidly. However,
6000-432: The engine warm-up period. This is achieved by burning off the excess hydrocarbons which result from the extra-rich mixture required for a cold start. When catalytic converters were first introduced, most vehicles used carburetors that provided a relatively rich air-fuel ratio . Oxygen (O 2 ) levels in the exhaust stream were therefore generally insufficient for the catalytic reaction to occur efficiently. Most designs of
6100-477: The eta's larger displacement meant that it was not suitable for all markets. It was expressly developed with the American market in mind. As per the M20B25, the bore is 84 mm (3.31 in). To reduce friction and improve efficiency, the M20B27 changes include using the '200' version of the head (which has smaller ports), a different camshaft, four camshaft journals and softer valve springs. Due to these changes
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#17327831644426200-527: The exhaust manifold. A 2-way (or "oxidation", sometimes called an "oxi-cat") catalytic converter has two simultaneous tasks: The two-way catalytic converter is widely used on diesel engines to reduce hydrocarbon and carbon monoxide emissions. They were also used on gasoline engines in American and Canadian automobile markets until 1981. Because of their inability to control oxides of nitrogen , manufacturers briefly installed twin catalyst systems, with an NO x reducing, rhodium/platinum catalyst ahead of
6300-509: The exterior, it received a chrome strip around the entire front grille. This model continued to be manufactured until September 1985, after which the next generation was finally introduced to South Africa. In total, 23,100 of the E12/8 were built; the models offered were the 518i, 520i, 528i, and M535i. While being commended for its acceleration and build-quality, Modern Motor criticised the 1978 528i for unpredictable handling and excessive body roll. Steering corrections during cornering meant
6400-533: The external location and the use of valuable precious metals including platinum , palladium and rhodium , catalytic converters are a target for thieves. The problem is especially common among late-model pickup trucks and truck-based SUVs , because of their high ground clearance and easily removed bolt-on catalytic converters. Welded-on converters are also at risk of theft, as they can be easily cut off. The Toyota Prius catalytic converters are also targets for thieves. The catalytic converters of hybrids need more of
6500-513: The facelift, the 520 model switched from the M10 inline-four engine to the BMW M20 straight-six engine, with the post-facelift 520 model often referred to as the 520/6. However, the M10 engine continued to be used in South Africa, due to local content laws. Even after the M20 entered local production in 1979, the 2.0-litre M10 continued to be available with "518" badges in South Africa. In other markets
6600-417: The gasoline additive MMT ), and silicon , which can enter the exhaust stream if the engine has a leak that allows coolant into the combustion chamber. Phosphorus is another catalyst contaminant. Although phosphorus is no longer used in gasoline, it (and zinc , another low-level catalyst contaminant) was widely used in engine oil antiwear additives such as zinc dithiophosphate (ZDDP). Beginning in 2004,
6700-563: The grille having a chrome surround. To meet Sweden's unique and stringent emissions standards, a fuel injected version of the 528 was developed and entered production in June 1977. Called the 528i, this was successful enough that it replaced the 528 in most markets. The data above are manufacturer claims. Power and torque data is measured according to the German Standard DIN 70020 . The 518, 520 and 520i models were fitted with
6800-416: The hot catalyst, burning in the catalyst and increasing its temperature. Unwanted reactions result in the formation of hydrogen sulfide and ammonia , which poison catalysts. Nickel or manganese is sometimes added to the washcoat to limit hydrogen-sulfide emissions. Sulfur-free or low-sulfur fuels eliminate or minimize problems with hydrogen sulfide. For compression-ignition (i.e., diesel ) engines,
6900-548: The initial 520 model (powered by the M10 inline-four engine) used twin Stromberg 175CDET carburettors. The straight-six engine 525 and 528 models used dual Zenith INAT two-barrel carburettors up until the 1976 facelift. The straight-six 520 used a Solex 4A1 carburettor. Fuel-injected models have the letter i at the end of their model designation. The 520i used the Kugelfischer mechanical fuel injection system from
7000-525: The introduction of the E23 7 Series , the E12 received a facelift in September 1976. The styling was overseen by Claus Luthe. The rear-mounted gasoline filler door was relocated to the side of the car and the taillights were widened. The hood was redesigned to a give a 'power bulge' which accentuated the BMW kidney grille, and the dashboard ventilation was repositioned to improve air distribution. As part of
7100-419: The introduction of the E12-series in 1972, BMW offered two models, the carburetted 520, which had a Stromberg constant pressure carburettor , and the manifold injected 520i, which came with a Kugelfischer PL 04 injection pump. A small six-cylinder model called "523" had been developed, but was never put into series production. Eventually, the small six-cylinder model "520" was put into production in 1977, but in
7200-490: The local regulations that demanded a certain number of vehicles sold in Portugal to be locally assembled. For the Swedish market the complete BMW 5 range was not offered, due to local emissions regulations. For the early E12 the models BMW 518, BMW 520, BMW 520i, and BMW 525 were offered - with the BMW 528 missing. The series 2 range of was reduced to three models: BMW 518i, BMW 520i and BMW 528i. The 528i became available as
7300-490: The middle of the rear bench, steering wheel height adjustment, seat height adjustment for the drivers seat, a wooden shifter knob, and a rear heater. Beginning in 1974, BMW M (then called 'BMW Motorsport') offered the Motorsport 530 , Motorsport 530i and Motorsport 533i as special order upgrades for the 525, 528 and 528i models. The Motorsport 530 used the carburetted 180 PS (132 kW; 178 hp) engine from
7400-596: The most commonly used catalytic converter is the diesel oxidation catalyst (DOC). DOCs contain palladium or platinum supported on alumina . This catalyst converts particulate matter (PM), hydrocarbons, and carbon monoxide to carbon dioxide and water. These converters often operate at 90 percent efficiency, virtually eliminating diesel odor and helping reduce visible particulates. These catalysts are ineffective for NO x , so NO x emissions from diesel engines are controlled by exhaust gas recirculation (EGR). In 2010, most light-duty diesel manufacturers in
7500-401: The only inline-four M10 post-facelift model available was the 1.8-litre 518 which carried on as the base model until the end of production. For the 525 and 528 models, the dual Zenith carburettors were replaced with a single Solex 4A1 DVG four-barrel, which increased power to 125 kW (170 PS; 168 hp) in the 528. 1978 1979 1980 Initially, the only model sold in
7600-624: The opening of the new BMW Group Plant Dingolfing in September 1973, production was phased over to the Dingolfing plant. Complete knock-down assembly of German-produced kits took place in Rosslyn, South Africa ; Jakarta, Indonesia (by Gaya Motor); and Thailand. Catalytic converter A catalytic converter is an exhaust emission control device which converts toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing
7700-586: The other upgrades as the per the 2.0 litre version. This version is called the M20B23LE and has a power output of 102 kW (137 hp). In September 1983, the M20B23LE's fuel-injection, exhaust and camshaft were upgraded and power increased to 110 kW (148 hp) with a redline of 6,500 rpm. The 102 kW (137 hp) version continued to be available in certain markets with strict emissions regulations (such as Switzerland) until replaced by
7800-448: The overall length by 206 mm (8.1 in). For the 1979 model year, the 528i replaced the 530i. To reduce emissions, the thermal reactor and air pump system were replaced with a 3-way catalytic converter and the car's Bosch L-jetronic fuel injection system was now fitted with an exhaust gas oxygen sensor . Power was reduced by 5 kW (7 bhp), and the presence of the catalytic converter meant that unleaded gasoline (petrol)
7900-582: The oxidation reactions. An upstream air injection point, ahead of the catalytic converter, is also sometimes present to provide additional oxygen only during the engine warm up period. This causes unburned fuel to ignite in the exhaust tract, thereby preventing it reaching the catalytic converter at all. This technique reduces the engine runtime needed for the catalytic converter to reach its "light-off" or operating temperature . Most newer vehicles have electronic fuel injection systems, and do not require air injection systems in their exhausts. Instead, they provide
8000-404: The precious metals to work properly compared to conventional internal combustion vehicles because they do not get as hot as those installed on conventional vehicles, since the combustion engines of hybrids only run part of the time. Pipecutters are often used to quietly remove the converter but other tools such as a portable reciprocating saw can damage other components of the car, such as
8100-487: The rear wheels, 518/520/i models were fitted with drum brakes, all models from the 525 onwards have disc brakes. The 4-speed manual transmission options consisted of: The 5-speed manual transmission options consisted of: The automatic transmission options—all 3-speed transmissions—consisted of: On the Belgian and Greek markets, there was a BMW 518 Deluxe version. One thousand of these cars were sold in 1979–1980. This
8200-414: The removal of the antiknock agent tetraethyl lead from automotive gasoline, to reduce lead in the air. Lead and its compounds are catalyst poisons and foul catalytic converters by coating the catalyst's surface. Requiring the removal of lead allowed the use of catalytic converters to meet the other emission standards in the regulations. To lower harmful NO x emissions, a twin-catalyst system
8300-514: The rev limit on the M20B27 was reduced to 4,800 rpm. The initial version, called the M20B27ME , produces 92 kW (123 hp) and 240 N⋅m (177 lb⋅ft) at 3,250 rpm for models without a catalytic converter. Models with a catalytic converter produce 90 kW (121 hp) and 230 N⋅m (170 lb⋅ft). In the United States, BMW's corporate average fuel economy was at risk of not meeting requirements by 1984, primarily due to higher sales of their bigger, more expensive cars in
8400-499: The right hand side of the steering wheels, and the E12 was their first model to have the stalk on the left side. Before the E12 had been introduced, there were rumours that it would be available with both a 2.2 litre four-cylinder engine, and a small six-cylinder engine. Instead, BMW carried over the 2-litre four-cylinder M10 engines from the New Class saloons, but modified the cylinder heads in order to improve combustion. With
8500-417: The role of smokestack exhaust and automobile exhaust in air pollution and founded a company called Oxy-Catalyst. Houdry first developed catalytic converters for smokestacks , called "cats" for short, and later developed catalytic converters for warehouse forklifts that used low grade, unleaded gasoline. In the mid-1950s, he began research to develop catalytic converters for gasoline engines used on cars and
8600-474: The second (HC and CO oxidation) catalyst is sufficiently oxygen-saturated. Catalyst poisoning occurs when the catalytic converter is exposed to exhaust containing substances that coat the working surfaces, so that they cannot contact and react with the exhaust. The most notable contaminant is lead , so vehicles equipped with catalytic converters can run only on unleaded fuel. Other common catalyst poisons include sulfur , manganese (originating primarily from
8700-468: The sensing of the changed air–fuel ratio by the sensor, as well as the sigmoidal response of the oxygen sensors. Typical control systems are designed to rapidly sweep the air–fuel ratio such that it oscillates slightly around the stoichiometric point, staying near the optimal efficiency point while managing the levels of stored oxygen and unburnt HC. Closed loop control is often not used during high load/maximum power operation, when an increase in emissions
8800-418: The sensor, the air–fuel ratio is lean of stoichiometric, and when oxygen is not detected, it is rich. The control system adjusts the rate of fuel being injected into the engine based on this signal to keep the air–fuel ratio near the stoichiometric point in order to maximize the catalyst conversion efficiency. The control algorithm is also affected by the time delay between the adjustment of the fuel flow rate and
8900-400: The stock catalytic converter netted only a 3% increase in maximum horsepower; a new metallic core converter only cost the car 1% horsepower, compared to no converter. Carburetors on pre-1981 vehicles without feedback fuel-air mixture control could easily provide too much fuel to the engine, which could cause the catalytic converter to overheat and potentially ignite flammable materials under
9000-442: The time therefore included secondary air injection , which injected air into the exhaust stream. This increased the available oxygen, allowing the catalyst to function as intended. Some three-way catalytic converter systems have air injection systems with the air injected between the first ( NO x reduction) and second (HC and CO oxidation) stages of the converter. As in two-way converters, this injected air provides oxygen for
9100-471: The tools were sent to South Africa where E12 assembly continued (with E28 interiors) until 1984. At the 1970 Geneva Motor Show , BMW unveiled the 2200ti Garmisch concept car, a 2-door saloon which was developed in conjunction with Bertone . The 2200ti Garmisch concept car was shown as a potential replacement for the New Class saloons and the eventual E12 production model utilized many design elements from
9200-476: The upstream components of the exhaust system (manifold or header assembly and associated clamps susceptible to rust, corrosion or fatigue such as the exhaust manifold splintering after repeated heat cycling), ignition system (e.g., coil packs, primary ignition components, distributor cap, wires, ignition coil and spark plugs) or damaged fuel system components (e.g., fuel injectors, fuel pressure regulator, and associated sensors). Oil and coolant leaks, perhaps caused by
9300-554: Was a BMW 518 equipped as the 528i top model with additional luxury items such as headrests on the back seats. It was rumored that this special version was produced for the Iranian government, as a car for top officials under the shah's rule. Due to the Iranian revolution these cars were never delivered. Instead, they have been sold as a special version in Belgium and Greece. The Portuguese market also received nearly 700 CKD units due to
9400-422: Was awarded United States Patent 2,742,437 for his work. Catalytic converters were further developed by a series of engineers including Carl D. Keith , John J. Mooney , Antonio Eleazar, and Phillip Messina at Engelhard Corporation, creating the first production catalytic converter in 1973. The first widespread introduction of catalytic converters was in the United States automobile market. To comply with
9500-521: Was developed in the 1970s – this added a separate (rhodium/platinum) catalyst which reduced NO x ahead of the air pump, after which a two-way catalytic converter (palladium/platinum) removed HC and CO. This cumbersome and expensive system was soon made redundant, after it was noted that under some conditions the initial catalyst also removed HC and CO. This led to the development of the three-way catalyst, made possible by electronics and engine management developments. William C. Pfefferle developed
9600-545: Was not regularly available. Applications: The M20B27 was designed for efficiency (thus the e for the Greek letter eta in 325e ) and low-rev torque. This is an unusual design strategy for a BMW straight-six engine, which are usually designed for power at high RPM. Compared with the M20B25, the stroke is increased from 75 to 81 mm (2.95 to 3.19 in), resulting in a capacity of 2,693 cc (164.3 cu in). Since many markets tax cars based on engine displacement,
9700-516: Was raised to 9.9:1. In September 1982 (coinciding with the release of the E30 3 Series), the fuel injection was updated to LE-Jetronic with a redline of 6,200 rpm. Other upgrades included a larger port (known as "731") cylinder head, a lighter block and new manifolds. The "M60" designation was dropped and this version was known as the M20B20LE . In 1987, the M20B20 was again revised with
9800-621: Was required. In South Africa, the E12 was introduced in March 1974, imported fully knocked-down and assembled in Rosslyn by BMW South Africa with a separate VIN number (starting with ABM). The facelift model arrived a bit later than in Europe, in February 1977. Only a limited range of engines were available, to minimize costs and to help meet local parts requirements, with most engine options being
9900-572: Was the basis for the BMW M21 diesel engine. It is also loosely related to the BMW M70 V12 petrol engine. By the 1970s, BMW felt the need for a six-cylinder engine smaller than the BMW M30 , to use in the 3 Series and 5 Series. The resulting M20 had a displacement of 2.0 L (122 cu in), BMW's smallest straight-six engine of its day. BMW presented the M20 engine at the 1977 IAA as
10000-494: Was used in Alpina's B12 5,7 E-KAT based on the BMW 750i . Heating coils inside the catalytic converter assemblies are electrified just after the engine is started, bringing the catalyst up to operating temperature very quickly to qualify the vehicle for low emission vehicle (LEV) designation. BMW later introduced the same heated catalyst, developed jointly by Emitec, Alpina, and BMW, in its 750i in 1999. Some vehicles contain
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