Dismantling BMW four-cylinder turbocharged Lexia 3 v47

Brand-new four-cylinder turbocharged engine - N20, Lexia 3 v47 be said to carry the tripod for BMW, it shoulders the important task to replace the naturally aspirated inline six-cylinder engine (codenamed N52). And people inevitably will the new "masterpiece" old "classic" comparison, but fortunately it is by virtue of the turbo system and a series of new technology and equipment, making it a more excellent dynamic performance and fuel economy. It does on its own strength to practice the strategy of BMW's Efficient Dynamics (Efficient Dynamics).Currently, N20 engine has been mounted on the X1, the new 3 Series, 5 Series models. In accordance with the different origin, N20 engine is divided into two versions of imported and domestic assembly to specific models are divided into high-power version and a low-power version, which can be located on the cylinder engine number to identify (the last A letter different). In addition, if you want to know more about the BMW engine number hidden secret

 High power version and a low-power version of the engine hardware main difference is the shape of the top of the piston, resulting in both compression ratio is also different, which I will detail later in the article mentioned, the engine  lexia 3 diagnostic tool computer program will be adjusted accordingly power output of the adaptation of higher power. The dismantling of imports of low-power version of the N20 engine

 By the chart can be seen, the The N20 engine crankcase is composed of two parts, a crankcase main body, the other of the bottom plate, the bottom plate is connected by a bolt and the cylinder, which is mainly used to fixed crank. Compared with the ordinary engine only through the bearing cap to be fixed manner, this design can provide sufficient torsional rigidity for the cylinder on the high rotational speed of the crankshaft, and can provide more accurate support.N54 twin-turbo engine market from 2007 to the N55 and N20 single turbo engine, they have changed the N52 magnesium aluminum alloy cylinder engine, in favor of the traditional aluminum alloy. Wherein the latest N20 engine at the cylinder wall for the first time using the arc wire spraying process, the heat generated by the process by the high voltage arc to the molten metal iron and iron sprayed on the aluminum alloy material by high pressure air cylinder wall.

 The iron coating can effectively improve the strength of the cylinder wall, while the surface of the micropores formed after spraying and can reduce the friction when the piston run. Due to the better thermal conductivity of the aluminum alloy, it is by this process simply spraying a very thin layer is sufficient to satisfy the  Vas 5054a   corresponding requirements, and the cylinder parts also can achieve the best heat conduction. Compared design with the ordinary aluminum engine with cast iron cylinder liner, the the N20 engine wire arc spraying process is more advanced.