Assignment

In the diagram (figure 2), the charger is, not without reason, shown as being larger than the engine. Also the elevated view shows a number of pipes which have been cut open and high-lighted for better representation. The Roots compressor which is flange-mounted, parallel to the engine block in the center of the picture, is particularly important.

This arrangement allows the constructor the almost limitless charging possibilities through a compressor and/or a turbocharger. To keep things simple, we want to single out two operating conditions. First of all, the lower RPM area. In this case, too little exhaust gas flows from the engine to build up an effective charging by the turbocharger. The compressor however, which is driven by the crankshaft, can provide powerful thrust without hesitation. In the upper RPM area, it is then switched off and by-passed, because now the full, and more favourable exhaust gas energy, can be used by the turbocharger. In this case, no hesitation (turbo lags) appear as far as the responsive properties are concerned. The result of these complexities is, an engine with a relatively small displacement which can develop (almost more) torque in the lower RPM area than a large engine. In addition, it revs higher, brings a better perfomance and apart from that, is still is relatively economical in it's fuel consumption.

Function

The air-hoses show the fairly complicated path of the air-intake. This is easier to understand when looking at the diagram ( figure 2). Here the air flows into the air-filter (1) and is the either accelerated by the compressor (3) or is sucked in through the bypass (2) by the compressor-wheel (5) of the turbocharger. Through the thrust diverter valve (4), the compressor-wheel can also be bypassed. Basically, it then goes on to the intercooler (6), through the throttle-valve (7) and the inlet manifold, to the individual cylinders.

As far as the path of the exhaust gas is concerned when leaving the engine, there is no difference to a customary turbocharger. It is led through the turbine-wheel (8) or through the bypass (9) to the catalytic converter (10). To ensure that everything is really controllable, the compressor can be activated or switched of by a magnetic coupling (11). 05/10