1. Boxer
horizontally opposed engine, and is unique secrets subaru of porsche.
The reason why the horizontal opposed engine is generally referred BOXER, because the intention is BOXER boxer engine cylinder which is divided into left and right sides, each side of the cylinder 2 or 3, the left and right sides of the pistons 180 degrees for the movement, like a boxer punching sparring, so was this call. Only Fuji Heavy Industries, the German Porsche have this engine technology in the world.
Characteristics
evenly distributed on both sides of the piston of the engine crankshaft, the left and right movement in the horizontal direction. Reduce the overall height of the engine, to shorten the length, the center of gravity of the vehicle decreases, more stable vehicle running, the engine is mounted on the center line of the vehicle, the torque generated by the piston on both sides cancel each other out, greatly reduces vibration of the vehicle during traveling, it greatly enhance the engine speed, reduce noise.
Low gravity: lateral vibration generated easily absorbed holder, will effectively reduce the engine center of gravity of the entire vehicle heavier, easier to achieve overall balance.
Low Vibration: good balance piston (180 degrees offset). Compared-line, the balance weight reduction factor required in terms of the crankshaft, to help improve the speed. It can maintain a low speed of 650 rpm, and to ensure a smooth engine operation. The same line compared to other engine minimum fuel consumption.
history
The biggest difference between the horizontal and the Porsche Subaru opposed engine mounting fact that: Subaru is a front longitudinally mounted engine, front wheel drive or four-wheel drive, with the average front transverse engine front-wheel-drive models are not the same, Subaru engine with Audi’s actually + Quadro V engine layout is very similar, is very typical of Symmetric AWD layout. Because only 4/6 EJ series engine cylinder capacity not exceeding 3000cc, front engine compartment space is abundant and therefore SubaruOnly we need to solve supply problems and the heat engine can be. In fact, Subaru engines are not very advanced or very special design, but now manufacturers are not using the same level to the level of design so unusual.
level of Porsche was first cooled from 6-cylinder 2.0L engine to start. 911 From the first day of the beginning of high-performance sports birth, so the above engine Porsche uses an expensive cutting-edge technology. 911 is the posterior longitudinal engine rear-wheel / four-wheel drive layout design air-cooled, small engine warehouse space available, Porsche design at the beginning of the space reserved only for 2.7L 2.7L is considered a limit.
In the 1970s the growing demand for horsepower, the implementation of catalytic converter / unleaded gasoline and the introduction of new emissions regulations allow Porsche urgent need to increase the engine volume. There are two options to increase the volume: an elongated stroke (increase in length), an enlarged diameter (increased width). Although Porsche can be greatly increased in the width of the rear of the engine compartment 911 Turbo space is increased, but this will greatly increase the air resistance and the cost is very high, not work in a normal 911. With the racing field accumulated technology and experience, Porsche found the breakthrough from the enhanced strength of the cylinder to reduce cylinder wall thickness increased cylinder bore, the application of new high-strength metal materials and electronic fuel injection engine 911 also allows the highest number of rotations and output increased dramatically. While the overall size of the engine is not significantly increased, but the above volume 2.7L engine 911 not to increase the width of the rear retaining overall layout optimization, between the engine and the gear box / shaft is connected to a tilt gear, with general automotive direct connect is different.
911 Flat 6 air-cooled engine in the 993 generation has been developed to limit the use of air-cooled design 3.2L limits of technology and in order to retain a cooling space, Porsche has been using less space SOHC 2V per clinder design, did not use the same generation engine has been the widespread use of high-performance DOHC 4V. Air-cooled engine was the Porsche 911 signs, but in the 911 GT1 / Porsche first test the water cooling Flat 6 DOHC design on the Boxster, and the use of water-cooled design on the next generation 996 911. Thanks to water-cooledDesign of an unprecedented volume 996 Engine 3.8L (911 GT3), fitted on the debut 993/968 Vario Cam (similar / i-VTEC system VVT-Li) raised to the maximum number of revolutions 7850rpm. In order to solve the horizontally opposed engine natural supply of oil, on the 911 Turbo / GT2 Porsche uses the highest standard of Dry Sump lubrication and three powerful pumps to enhance the performance of 911 in the number of high G’s, while retaining the premise of 13,000 miles service intervals under horsepower upgrade to the appalling 472 (3.6L Turbo).