When we say Polaris, we often say "Polaris V8 engine", which is the reason. This engine first appeared on 1993 Cadillac Allante, Eldorado and Seville STS. Because it is a V8 engine, other models in the GM family rarely enjoy this engine except Cadillac, so Cadillac and Polaris engines are virtually dead. When it comes to Cadillac, people often think of Polaris engine.
At that time, this Polaris V8 was code-named L37 with a displacement of 4.6 liters. General motors is not a good hand in producing high-quality engines, but the birth of Polaris is of epoch-making significance to general motors.
Don't think that this is exaggerating the role of an engine. In fact, from the 1980s to the early 1990s, automobile products were not as they are today-there was basically no big difference in the technology of the same class of cars, but the brand culture and vehicle configuration were different-and at that time, the standard of calling a car good or bad was often determined by the core technologies such as engine, chassis and transmission. Unfortunately, many people in China no longer buy cars for it.
So when the First Taipei Polar Star appeared with 295 horsepower, it was the first V8 aluminum alloy engine with overhead camshaft in the United States, which conquered many Americans and won the reputation of "American 10 engine" awarded by Ward Automobile World. In fact, the top 10 products that can make the Ward engine rankings are first-class in the industry. I believe everyone knows this.
For example, Nissan's VQ series won the title of Ward 10 engine in 10, which is strong, hehe. At that time, Polaris, with its excellent rising power, excellent fuel consumption performance and reliable performance, dwarfed the same displacement engines of Mercedes-Benz and BMW in the American market and greatly increased the prestige of Americans.
Because of this, Polaris, like American Mustang and Corvette, has become the flagship product of American automobile industry in culture and spirit, but its history is not very long. Naturally, GM will not let this engine be a flash in the pan, so Polaris V8 has embarked on the road of continuous improvement and development.
1994, the first L37 Polaris V8 engine ushered in its second version, LD8. The cam shape of LD8 has been rebuilt, and the horsepower has been reduced a little, only 270 horsepower, but the torque at low speed has been increased, and the engine's response to the throttle has been obviously strengthened, bringing a more ideal sense of acceleration.
In the same year, a smaller and weaker Polaris appeared on the aurora in Oldsmobile. This Polaris 4.0-liter V8 engine named L47 is not much different from the previous 4.6-liter V8 engine, mainly because GM changed the cylinder diameter and stroke (87mm*93mm), so the displacement is small and the maximum horsepower is only 250 HP. 1995 The first generation L37 Polaris 4.6-liter V8 engine was adjusted to a new height, with 300 horses.
The LD8 version of Polaris also rose to 275, although it was only a poor five. That is to say, by 1995, the Polaris engine with a displacement of 4.6 liters will have two horsepower versions, 275 and 300 respectively.
It is worth mentioning that Polaris L37 and LD8 have been in use until today, and their service life is not long. GM has no plans to replace these two models with new products. At present, Cadillac DTS uses V8 of L37, and Buick Lucerne uses V8 of LD8.
GM also introduced the Polaris XV 12 concept engine, which is basically the same size as the current V8, but the horsepower has reached an astonishing 750 horsepower, which is absolutely a player-level heart. GM has adopted "cylinder activation technology" to ensure that the fuel consumption of the engine will not be too high, but there has been no sign of mass production of the engine. It seems that the concept engine is really used to play with "concepts", not for mass production. Your saliva can be taken back! (Don't drool? That better be the best! ) In 2004, Polaris engine code-named LH2 appeared on Cadillac XLR and SRX, and LH2 was also used in Cadillac STS in 2005.
LH2 is an engine with VVT variable valve timing in Polaris family at present. It also brings a brand-new ETC electronic throttle technology, which benefits other Polaris engines and can be gradually equipped with ETC. In addition, there is a new engine control unit E67, which is used in Polaris from front drive to rear drive and four-wheel drive, and its layout has changed from horizontal to vertical. In addition to LH2, Polaris also added a V8 code named L37, which is basically the same as LD8, only a derivative version.
At present, the whole Polaris family has four engines, namely, 4.4L V-8 SC (LC3), 4.6L V-8 (L37), 4.6L V-8 (LD8) and 4.6L V-8 VVT (LH2). General characteristics of the engine The cylinder liner of Polaris V8 engine is made of aluminum alloy by die casting. After 2000, GM adopted a new high-pressure casting process to reduce the porosity of aluminum alloy in the forming process, thus reducing the porosity of aluminum alloy parts in the engine and improving the performance.
Before 2000, the compression ratio was 10.3: 1, and after 2000 it was adjusted to 10: 1. The design of double camshafts and four valves per cylinder conforms to the trend of large displacement engines, and there is nothing special to say.
The camshaft adopts chain drive, which is more durable than belt drive. Polaris V8 has a bad problem, that is, there is a problem with the chain, and there will be a big problem with the cylinder. No one wants to see this problem with such an expensive engine.
The intake manifold is made of thermoplastic nylon 66, which can cool the intake air without being affected by the heat of the engine, thus maintaining a good working condition. Polaris enters the cylinder through the general SFI (sequential fuel injection) fuel injection method, and the position of the intake and exhaust cam is controlled by the sensor, thus accurately matching the gas entering and leaving the cylinder.
The ignition system has two control modes. One is "ignition control mode", in which the time and angle of pre-ignition are calculated by the computer according to the data obtained by sensors inside and outside the cylinder. When there is a problem with the computer or sensor, the engine will be in "predetermined module mode".
2. Introduce the history of general Polaris engine. Each brand has its own characteristics that are different from other brands. The best and only way to maintain this feature for a long time is to rely on leading technology.
Just as Volkswagen has the best FSI and TDI technology and Toyota has superb VVT-I technology, GM also has the world-renowned best engine assembly-Polaris series engine. 1996 Polaris 32valve v8 engine Polaris engine first appeared in 1993 Cadillac Arante, Elrado and Seville STS, code L37.
At the beginning, it was precisely because of its V8' s large displacement that almost all of it was configured on Cadillac, a luxury brand. 1994, L37 Polaris V8 engine ushered in the updated version LD8 through improvement.
The biggest change of LD8 is to redesign the cam curve, which reduces part of the engine power, but increases the engine low-speed torque. Therefore, LD8 is more suitable for heavy-duty SUVs like SRX. During the period of 1995, the output horsepower of Polaris L37 and LD8 engines was adjusted to 300 and 275 respectively.
Since then, these two Polaris engines have not changed and have been used until now. Polaris -V8 engine was equipped with Cadillac XLR in 2004. In 2004, Polaris engine code-named LH2 appeared on Cadillac supercar XLR and luxury SUV——SRX, and this LH2 Polaris engine also appeared on Cadillac STS in 2005.
This new LH2 adopts VVT variable valve timing technology, which was first applied in American engine history. This technology allows the intake valve and exhaust valve to independently control the opening and closing time. By adjusting from low speed to high speed operation, the valve can be opened and closed at the most appropriate time, and the fuel injection can be controlled accurately, so that the combustion efficiency of gasoline in the cylinder can be improved more effectively, and the cleanliness and performance of engine exhaust gas can be improved.
In addition, LH2 also brought a brand-new ETC (Electronic Throttle Technology) system to replace the mechanical transmission between the accelerator pedal and the accelerator. The accelerator pedal position sensor, engine control sensor, automatic cruise command, anti-skid control record and shift energy command sent by the engine control module are sent to the accelerator control unit of the engine, thus changing the throttle size.
The system helps to minimize fuel consumption, while ensuring strong power, direct response and clean emissions. After LH2, L37 and LD8 are also equipped with ETC control units.
In addition to LH2, LC3 engine LC3 engine is equipped with a brand-new 4.4L displacement Polaris V8 supercharged engine, code-named LC3, which was specially developed by Cadillac for its V-series sports car. The engine provides power performance comparable to that of racing cars, and is loaded on STS-V and XLR-V. So far, there are four engines in the Polaris family, namely 4.6V8 (L37), 4.6V8 (LD8), 4.6V8VVT (LH2) and 4.4V8 (LC3).
General characteristics of Polaris engine: Polaris V8 engine is made of aluminum alloy, and the engine cylinder block is made of die casting technology. After 2000, GM adopted a new high-pressure casting technology, which solved the porosity problem of aluminum alloy during cooling molding, reduced the porosity of aluminum alloy parts in the engine and improved the engine performance. In addition, before 2000, the compression ratio of Polaris engine was 10.3: 1, and after 2000, it was changed to 10: 1 to adapt to the design of double camshafts, four valves and chain-driven camshafts per cylinder.
Finally, the intake manifold of Polaris engine is made of thermoplastic nylon 66. The intake manifold made of this material can cool the intake air without being affected by the heat conducted by the engine, thus maintaining a good engine intake environment. In addition to the above, Polaris engine has another feature, that is, it can continue to run when all coolant fails. This is the so-called "limping home" mode.
In this mode, when the computer detects that the engine is overheated, it will temporarily stop half of the cylinders, which will lower the temperature of the whole engine so that the vehicle can continue to drive, but General Motors added a note: in this case, the vehicle can only drive 50 miles at most. The fifth member of Polaris family: At present, the newest member of Polaris engine family is the concept engine of Polaris XV 12, which was introduced with the concept car CIEN.
This engine is a V 12 engine, with a 60-degree cylinder angle, an all-aluminum double overhead camshaft (DOHC), a single cylinder with four valves and a displacement of 7.5 liters. It can output 750 horsepower and 450 lb/ft of torque, but it is as compact as a V8 engine.
Thomas Stephens, vice president of the powertrain department of General Motors, who designed this engine, said: "Although there are many powertrain products of General Motors, we have not developed the V 12 engine so far, and this is exactly the field that our Polaris XV 12 engine is exploring. The important difference between our car and other products in the premium car market lies in the powertrain, and XV 12 engine with many advanced technologies can meet the shape requirements and fuel economy standards of most V8 engines, which makes GM naturally take the lead in this field.
At the same time, this engine inherits some of our design traditions. Steve Kowalk, project manager and engineer of general motors Polaris XV 12 engine, said, "The shape may be one of the biggest challenges we face, because we wanted to make the V 12 engine the same size as the V8 engine from the beginning.
We try to reduce the size of the engine so that it can be used in as many cars as possible. At the same time, we should also maximize the engine displacement and use the' variable displacement' technology to provide the required power at any time.
We reduced the cylinder wall thickness to 7 mm, and adopted the rear camshaft drive mode, which made the cylinder more compact and the hood lower. XV 12 engine Compared with other Polaris engines, the advanced technologies adopted by Polaris XV 12 engine include: l. "Variable displacement" technology.
3.F Lockdyne originally designed F- 1 only because 1955 the US Air Force put forward the requirement of manufacturing very large rocket engines. The company finally designed two versions, one is E- 1 and the other is F- 1. Although E- 1 succeeded in the static ignition test, this engine was soon considered to have no future, and a more powerful F- 1 existed, so the E- 1 plan ran aground. However, the US Air Force found it unnecessary to use such a powerful engine, and the research plan of F- 1 was also suspended. The newly established National Aeronautics and Space Administration (NASA) took a fancy to this engine and signed a contract with Lockdyne to complete the research and development work as soon as possible. The engine was partially tested during 1957, and the static ignition test of the whole engine was also successfully carried out in March 1959.
F- 1 In the following 7 years of tests, its combustion instability was gradually exposed, which may lead to catastrophic accidents. [1] At first, the work to overcome this technical problem was very slow, because the occurrence of this kind of fault was unpredictable. Finally, the engineers came up with a solution. They put a small amount of explosives in the combustion chamber and detonated them when the engine was running to test how the combustion chamber would react when the pressure changed. The designer then tested several different injectors and got the best matching scheme. This problem was delayed from 1959 to 196 1 year.
4. Engine 15e4e Which country's engine belongs to China SAIC?
1. This 1.5T 15E4E engine of SAIC-GM Buick and Chevrolet is inextricably linked with the 1.5T LFV engine. SAIC and General Motors jointly developed two series of engines, namely SGE (small gasoline engine) and MGE (medium gasoline engine).
2. The 1.5T and 2.0T engines on Roewe RX5 are the same as those on MG Ruiteng, which was listed earlier, and they are all produced by SAIC Lingang Factory. Matching with 1.5T engine is a 6-speed manual gearbox and a 7-speed dry dual-clutch gearbox, and matching with 2.0T engine is a 6-speed wet dual-clutch gearbox.
Placing the spark plug and the fuel nozzle at the top of the combustion chamber and the center of the four valves at the same time puts forward higher requirements for the design of the cylinder head, and it is more difficult to manufacture than the side nozzle.
With the upgrading of direct injection technology, it is estimated that the fuel injection pressure of engine products in the industry will increase to about 400bar before 2020, so as to improve the fuel atomization efficiency and further limit the particulate emission of engines.
The air intake and relief valve of the turbocharging system of 1.5T 15E4E engine are integrated on the turbocompressor, and are in the form of electronic control. When the driver suddenly receives oil, the valve will open.
Connecting the supercharged side and the non-supercharged side of the turbocharger compressor reduces the impact of the high-pressure intake air flow on the throttle valve with a sudden decrease in opening, and also avoids the impact of the rapid decrease in turbine speed on the engine speed-up performance again.
In addition, the 1.5T 15E4E engine uses a variable displacement oil pump, which can control the displacement of the oil pump according to the engine load and speed, avoid energy waste caused by excessive pumping, and help reduce fuel consumption.
Extended data:
Composition of automobile engine model
1. Header: includes product series code, replacement code and local and enterprise code, which are represented by the corresponding letters selected by the production enterprise according to the needs, but must be approved and filed by the centralized department of industry standard standardization.
2. The middle part is composed of cylinder number symbol, cylinder row symbol, stroke symbol and cylinder diameter symbol.
3. Rear part: It consists of structural feature symbols and use feature symbols.
4. Tail: Distinguishing symbol. When the same series of products need to be differentiated due to improvement and other reasons, the manufacturer should choose appropriate symbols, and the "-"sign can be used at the back and tail.
References:
Roewe official website-Roewe RX5
5. History of gasoline engine Review of the historical development of automobile engine The overall technology of automobile is changing with each passing day, and as the heart of automobile, the progress of engine technology is more concerned. Nowadays, when an automobile engine is introduced, variable valve timing technology, double overhead camshaft technology, in-cylinder direct injection technology, VCM cylinder management technology and turbocharging technology have been widely used. The materials used are also developing in the direction of lightweight: all-aluminum engines have been widely used at present; Automobile pollution is inevitable, so new energy technologies, including diesel engine high-pressure rail, fuel cell, hybrid power, pure electric power and biofuel technology, have also begun to spread. But looking back on the history of engines, we may better understand the great changes that have taken place in automobile technology in the past 100 years.
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VQ35 Top Ten Engines
The rapid development of automobile technology can also be seen from the automobile textbooks in China: the development of new technology has made it difficult for automobile textbooks to keep up with the pace! At present, most automobile teaching materials still take Dongfeng engine as an example. Dongfeng engine is still an old-fashioned engine of carburetor, which is almost separated from today's all-electronic engine for centuries.
Exploration stage before gasoline engine
Back in auto start, the car was laughed at by the carriage at that time, which caused serious pollution, but the significance of starting was extraordinary.
/kloc-in the middle of the 0/8th century, Watt invented the steam engine, and people began to imagine putting the steam engine on a car to carry people. N.J.Cugnot of France was the first person to install a steam engine in a car. 1770, Guniu built a three-wheeled steam locomotive. With a total length of 7.23 meters and a speed of 3.5 kilometers per hour, it is the first steam locomotive in the world. 177 1 year, Cournot improved steam car, with a speed of 9.5 kilometers per hour, pulling 4-5 tons of goods.
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Steam engine car
1858, Renault, who lived in Paris, France, invented the gas engine and applied for a patent in 1860. The engine uses the mixture of gas and air to replace the steam of the reciprocating steam engine, uses batteries and induction coils to generate electric sparks, and uses the electric sparks to ignite the mixture and explode. This engine has a cylinder, a piston, a connecting rod and a flywheel. Gas engine is the primary product of internal combustion engine, because the compression ratio of gas engine is zero.
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Noun (short for noun) Kunot
1867, inspired by Reno's development of gas engines, Nicolaus August Otto, a German, made a lot of research on gas engines and made a horizontal pneumatic gas engine. After improvement, his samples were exhibited at the international exhibition held in France in 1878. Because of its high working efficiency, this engine has aroused great interest of visitors. In the long-term research process, Otto put forward the four-stroke theory of internal combustion engine, which laid a theoretical foundation for the invention of internal combustion engine. Germans Omray and karl benz developed their own modern gasoline engine according to the principle of Otto engine, paving the way for the development of automobiles.
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Mercedes-Benz 1 is equipped with a single-cylinder two-stroke gasoline engine.
1886 is the birth day of the car, and that Mercedes-Benz has always been talked about. But its power plant is really "shabby": the first "three-wheeled Mercedes-Benz" is equipped with a horizontal single-cylinder two-stroke gasoline engine with a top speed of 16km/h, which is the engine of the first car. At that time, Carl Benz's brave wife needed her son's cart to drive this Mercedes-Benz 1 uphill. Of course, the engine was turned off all the way, and the steering wheel didn't work. 100km. It took me a whole day to go back to my parents' home.
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Working diagram of four-stroke engine
The four-stroke engine was actually invented by Otto, a German. But Daimler has to be mentioned in the application car. He became the first person to install a four-stroke engine on a car because he helped Otto develop the four-stroke engine. Obviously, from four-stroke to two-stroke is a great progress. The four-stroke engine has better balance and combustion efficiency. Now the automobile engine technology has basically adopted the four-stroke technology. However, after the basic operation mode of the engine was determined, some people once again challenged the tradition.
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Mazda special rotary engine 1957 and German Wankel invented rotary piston engine, which is an important branch of gasoline engine development. The characteristic of rotary engine is that the triangle piston motion is directly converted into rotary motion by combining the inner rotor epicycloid and the outer rotor epicycloid, without crankshaft connecting rod and valve train. Compared with reciprocating piston gasoline, it has 40% fewer parts, light weight, small volume, high speed and high power. 1958, Wankel changed the outer rotor into a fixed rotor with planetary motion, and made a new rotary piston engine with power of 22.79 kW and speed of 5500 rpm. This machine has important development value, so it has attracted the attention of all countries. Japan Toyo Company (Mazda Company) purchased the prototype of the rotary engine and installed it on the car. It can be said that the rotary engine was born in Germany and grew up in Japan. Today, the rotary engine is still only used by Mazda. I don't know when Mazda's unique technology will fully blossom.
After the working form of the engine is determined, the engine technology is perfect. With the passage of time, many classic engine designs can no longer meet people's needs.
6. History of VQ series engines * * The same features of VQ series engines are V-type 6-cylinder form, all-aluminum cylinder block material, DOHC overhead double camshaft, 24-valve structure and EGI sequential multi-point injection system. The later version is equipped with NICS variable intake control system, CVTC continuous variable valve timing control system and VVEL variable valve lift system.
During this period, VQ25DD/VQ30DD engines with NEO-Di in-cylinder direct injection technology and a series of turbocharged high-performance versions were also introduced. Since its launch, VQ series engines have been widely used in Nissan's mid-to high-end cars, sports cars and British finidi models.
Starting from 1995, the authoritative American automobile magazine "Ward Auto World" will select the top ten engines of the year every year. The selection criteria are mainly to compare the comprehensive performance, power output performance, torque, versatility, economy, environmental protection requirements, forward-looking and other items of the selected engines. VQ series engines were selected for 14 times from 1995 to 2008.
7. What about the engine of MG 61.5t? The position of MG 6 1.5T in SAIC. The model of 1.5T engine on MG 6 is 15E4E, which is closely related to the 1.5T LFV engines of Buick and Chevrolet under SAIC-GM.
SAIC and General Motors jointly developed two series of in-cylinder direct injection engines, namely SGE (small gasoline engine) series and MGE (medium gasoline engine) series. Sge msense1.0t2.0l1.3l1.4t1.8t1.5t2.0t1.5t Watchmaking: SAIC, the Pacific Auto Network, announced 20 15.
At present, NetBlue has three sub-engine series: SGE, MGE and NSE. SGE and MGE series correspond to small and medium displacement engines respectively. It is worth noting that both SGE series and NSE series have 1.5T engines.
These two engines are different. SGE series 1.5T 15E4E engine is the 1.5T engine on MG 6 mentioned in this paper, and the MG GT is equipped with NSE series 1.5T 15S4G engine. The performance index of SGE 1.5T engine introduced later is better than that of NSE 1.5T engine.
1.5T 15E4E engine In this paper, the models currently used by MG brand are MG 6 and MG GS. In addition, this engine now appears on Roewe i6 and RX5, but * * * is different.
Comparison of engine power between MG 6 1.5T and Angkor 1.5T MG 6 1.5T Angkor 1.5T model 15E4LFV cylinder number 4 4 Maximum power of direct injection in cylinder (kw/rpm)124. 5600 Maximum torque (n m/rpm) 250/1700-4300 250/1700-4400 Watchmaking: Pacific Auto Network Because this 1.5T 15E4E engine is SAIC and GM * *.
The 1.5T 15E4E engine of MG 6 is currently produced in SAIC Lingang factory. 6-speed manual gearbox and 7-speed DCT gearbox match 1.5T engine. What is the power of MG 6 1.5T? IV/KOOC-0/.5t engine power comparison manufacturer SAIC Honda Ford BMW model/KOOC-0/5e4EL/KOOC-0/5b8aecoboost B38A/KOOC-0/5c cylinder number 4 4 3 engine displacement (ml)/KOOC-0/490/KOOC-0/498/KOOC-0. Fuel injection mode Maximum power of in-cylinder direct injection (kW)124130133100 Maximum power speed (rpm) 5500 6000 6000 4400 Maximum torque (n m) 250 220 240. 0700-43001700-5500150-45001250-4300 Watchmaking: Compared with the joint venture 1.5T engine, the maximum power of MG 6 is slightly weaker than that of Ford and Honda.
Of course, again, the data on the account is only part of the judgment, and the overall driving experience and fuel consumption performance should also be considered. IV 1.5T engine power comparison manufacturer SAIC JAC Changan Great Wall Harvard model15E4 HFC 4GC1.6DL476ZQCA GW4B15 cylinder number 4 4 4 4 engine displacement (ml)14901490. Kloc-0/499- Direct injection engine oil mode Maximum power of direct injection in cylinder (kW)66 rpm1700-43001500-45001950-45001400.
Power Comparison of MG 6 1.5T Engine 1.5T Normal Edition 1.5T High Performance Edition Cylinder Number 4 4 Fuel Injection Mode Maximum Power in Cylinder (kW) 124 140 Maximum Torque (N m) 250 300 Tabulation This version of the engine belongs to the high-performance version, and the maximum power and torque are improved compared with the ordinary version.