dream of sticking with tradition, today the achievements of the Subaru boxer engine profound accomplishments 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 into SOHC (single overhead camshaft) and OHV of (underfloor 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 excellence, while 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 ldquo horizontally opposed engine; rdquo temper mettle ; and the technology precipitation also buried deep foreshadowing for the second generation shine EJ series engine.
EJ series of second-generation boxer engine mdash; mdash; shine
1989 years, 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 camshaft, using SOHC or 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, the high-performance division Subaru launched STI versions of the Impreza, which is also equipped with a EJ20G engine, by upgrading to strengthen the power output of the engine upgrade to 250 horsepower. It should be said, EJ20 STI along with the evolution of more and morePowerful, 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, 4G63 every time after the appearance of Evo as power generation becomes stronger, Subaru EJ20 will always be followed by a corresponding upgrading to strengthen compete with them. Both is such magic goes, the Road ridge let each other in ldquo; genetic variation rdquo; in competitive advantage.
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.
Worst voice mdash; mdash; red top EJ207
At its peak early EJ20G engine started Subaru full 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 can be described as the most obvious signs of this engine, since the STI from the fifth generation, ignition EJ207 this packet from the initial to the subsequent independent ignition from IHI (Ishikawajima-Harima heavy Industries Co., Ltd.) to a 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.
from the series EJ20 large bore (92mm), a small stroke (75mm) design, and a counter piston during operation of the inertia force generated by pulling each other, so that not only has EJ207 fast dynamic response, while at 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 producers, the level of research and development in the world of the mid-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.