The VR engine is Volkswagen's exclusive product. In 1991, Volkswagen developed a V6 2.8L engine with a 15° angle, called the VR6, and installed it on the third generation of golf. The engine is compact and has a width close to that of an inline engine and is no longer than an inline 4-cylinder engine.
As we all know, for the V-type 6-cylinder engine, the 60-degree angle is the optimal design, which is the result of numerous scientific experiments. Therefore, most V6 engines adopt this layout. However, in order to be able to put down the V6 engine in a smaller space, the Volkswagen Group has developed a VR6 engine with a 15 degree angle and a smaller size. From the perspective of dynamic parameters, it is not inferior to the ordinary V6 engine, but it has exposed obvious jitter problems at the beginning of development. The problem has been significantly improved through a series of balanced stabilization methods. But this still can't go beyond changing its own structural characteristics, just like the vibration of a normal inline engine is usually greater than that of a V-type engine. The smaller angle of the VR6 determines that its vibration will be greater than V6. Such engines have been assembled in models such as Volkswagen's Golf R32 and EOS.
The cylinder angle of the VR engine is very small, the two rows of cylinders are nearly parallel, and the holes of the spark plug on the cylinder head are almost in a straight line. The VR engine is characterized by its extremely small size, so it is very suitable for the front engine platform of the Volkswagen car, because Volkswagen's front engine front wheel drive chassis is a vertical design, and the engine is not too long before the front axle. Otherwise it is difficult to arrange the front suspension. This engine is very compact, although it is a V-cylinder machine, but because the two columns of cylinders are very close, only one cylinder head is needed, which is much lower than the V6 at 90 degrees and 60 degrees (because the ordinary V-cylinder machine) Two cylinder heads must be machined. If it is a DOHC V cylinder machine, it also needs to machine 4 camshafts, so the cost is high).