1.EJ20
to adhere to the dream and heritage, the achievements of today’s Subaru boxer engine profound knowledge in the field level. It is the second generation of the engine as Subaru products bright star, EJ20 Subaru boost the award-winning series on the WRC arena, and helpless love and hatred between it and Mitsubishi, just like the evolution of species in general, let each other have become increasingly powerful.
In understanding the EJ20, EJ20 let us look at the origin
The first generation EA Series boxer engine mdash; mdash; accumulation and precipitation
from Subaru initially chose a different growth path. With the advent of the first Subaru 1000 model, it was found that the use of horizontal pioneering Subaru 4-cylinder engine with dynamic transmission mode opposed front wheel drive. This is the 60s of last century, the vehicle also common for the Japanese Rear-wheel drive inline engine +, is particularly maverick.
Initially, Subaru’s engineers carefully studied the relevant Porsche and Volkswagen models. They believe that using opposed horizontal layout of the engine may be a good match in the form of front-wheel drive, thus eliminating the need for relatively bulky drive shaft. Not only can save interior space, but also greatly improve the transmission efficiency. However, this high-profile technology at the time, but there are many technical problems, but Subaru was determined to go to overcome difficulties. On stage this technology is not a flash in the pan, then, horizontally opposed engine is always accompanied by Subaru cars, in the future also become a special card.
Early models provided on Subaru EA series, i.e., the first generation of four-cylinder horizontally opposed engine is water-cooled, two valves per cylinder design, but also divided into SOHC (single overhead camshaft) and OHV (bottom-mounted camshaft) two. By increasing the compression ratio and other technical means, the EA53 engine has an annual output of 1967 can be done liter 50kW power close to the level of excellenceWhile the maximum speed reaches 6600rpm. At the same time, engineers also by way of the expansion of the bore, this series 1.0L engine development from the earliest to the late 1.8L, to meet the different needs of each vehicle.
Although the EA series Subaru engine did not make a name for themselves, but more than two decades of accumulated technology, let Subaru’s engineers figured out every three years boxer engine, and this technique also precipitate the second generation shine EJ series engine buried deep foreshadowing.
EJ series of second-generation boxer engine mdash; mdash; shine
In 1989, Subaru introduced a new model mdash; mdash; Legacy (Legacy), will also target the WRC arena, to fight was fast Toyota, Mitsubishi and other manufacturers. At the same time, the second generation boxer engine EJ series also took the banner of their predecessors, and mounted on the Legacy model, began to emerge.
EJ range from 1.5L to 2.5L engine has a plurality of displacement, they abandon the first generation of relatively old technology OHV underfloor camshafts, or use SOHC DOHC. The number of valves per cylinder 2 changes from the original 4, which greatly improves intake and exhaust efficiency of the engine at medium and high speed, while it is divided into two naturally aspirated and turbocharged versions.
the mainstay of the EJ20
1992, with the launch after Mitsubishi Evolution, Subaru felt the crisis quickly responded immediately launched to rival Impreza (wing leopard) WRX models, but Subaru has not forgotten to be powered by a strong performance of its engines. Thus, once mounted on Legacy models, the displacement of the turbo engine EJ20G 2.0L Impreza will appear in the nacelle, and it also increased from the initial power of 220 hp 240 hp.
In 1994, Subaru introduced the high-performance sector STI versions of the Impreza, which is also equipped with a EJ20G engine, enhanced by upgrading the engine, power output raised to 250 hp. It should be said, EJ20 along with STI’sEvolution is going strong, and ultimately achieve the prescribed limit of 280 horsepower. However, progress in the process EJ20, ultimately, from the opponents, especially spur Mitsubishi 4G63 engine.
Interestingly, every time with a new generation Evo 4G63 after the appearance and power become stronger, always followed by Subaru EJ20 will make the appropriate upgrades to strengthen compete with them. Both is such magic goes, the Road ridge let each other get a competitive advantage in genetic variation.
in 1995, 1996 and 1997, the Subaru Impreza WRX models get three manufacturers titles in the World Rally Championship in a row, which is the Japanese auto makers for three consecutive years for the first time in this rally game award. However, the cars are equipped with precisely the EJ20 engine, Subaru consistently opposed efforts to the development level of the engine has finally paid off.
in the history of the strongest voice mdash; mdash; red top EJ207
as early as the heyday EJ20G engine, Subaru began full-scale development of the EJ207. In 1998, with the advent of the fifth-generation STI, was regarded as artifacts of EJ207 engine fans also opened its mysterious veil. EJ207 hardened, the output power has to withstand much higher than the upper limit of 280 horsepower. However, this engine exclusively for the Japanese version of STI model, does not carry on export overseas Subaru models.
Red intake manifold described this engine the most obvious sign, from the fifth generation STI far, this EJ207 from the first packet ignition later independent ignition from IHI (Ishikawajima-Harima Heavy Industries Co. Ltd.) to the turbocharger VF28 VF34 (corresponding faster), but also to enhance the process and ultimately the cylinder, piston, crankshaft and other components, and manufacturing precision. Although EJ207 in durability or less 4G63, but with a boxer engine unparalleled features low center of gravity, making the Subaru models icing on the cake in the control area.
EJ20 series from large bore (92mm), a small stroke (75mm) design, and mutually pulling force of inertia of the piston during operation opposed generated, so that not only has a fast EJ207 dynamic response, at the same timeAt high speed can be maintained strong torque output. Advantage of this innate structure, perhaps Subaru has always insisted on a horizontal opposed engine of the important reasons.
Although Subaru’s engineers continue to make changes in the details for their work, but EJ207 still there are some shortcomings. One is located in the lower part of the engine exhaust manifold is too long, while the turbocharger is precisely located in the upper part of the engine, so that the exhaust gas over a period of long channel to reach the turbocharger, which will inevitably lead to noticeable turbo hysteresis effect. The second point is located in the layout design of the turbocharger next to the cold, tremendous heat generated by the work it will cause poor cooling in the intercooler, so as to reduce intake efficiency. Of course, these problems can not hinder EJ207 become a classic, it still makes a huge potential modification enthusiasts in droves.
EJ20 series engine in good predecessors inherited good genes, this technology will be carried forward and did the best publicity for the Subaru brand, and as the culmination of the EJ207 boxer engine of the year , with low center of gravity, high speed and huge potential for conversion to be talked about later, but also as a wonderful work of art and the history of human history.
As one of only two in the world in production, research and development of one of the boxer engine manufacturers, Subaru contribution to this technology is unique. Perhaps foresight, Subaru symmetrical four-wheel drive to the left and right boxer engine tenacity and later developed can be described as a perfect match, a combination thereof from the engine to the transmission, from the splitter to the rear drive shaft and then to a differential, all the parts were tested aligned. Combination of mechanical engineering, Subaru will be the full benefits Taken together, front to back, from left and right to create the ideal weight distribution, but also the balance of the vehicle near perfect.