Turbocharger System

TURBOCHARGER SYSTEM
DESCRIPTION

CAUTION: The turbocharger is a performance part and must not be tampered with. The boost pressure bracket is an integral part of the turbocharger. Tampering with the boost pressure components can reduce durability by increasing cylinder pressure and thermal loading due to incorrect inlet and exhaust manifold pressure. Poor fuel economy and failure to meet regulatory emissions laws may result. Increasing the turbocharger boost WILL NOT increase engine power.

The turbocharger used on this vehicle is of the variable turbine type. These turbochargers use the entire exhaust energy to boost efficiency of the turbocharger and the engine.

The advantages of a turbocharger with variable turbine geometry are:
^ Higher charge pressure already in the lower and in upper engine speed ranges.
^ Higher torque as a result of improved cylinder charge.
^ Reduction in exhaust emissions as a result of an improvement in the air supply of the engine.
^ Increased power output as a result of the higher charge pressure combined with a reduced exhaust back pressure and thus improved charge cycle.

OPERATION





The exhaust gases of the engine are directed through the exhaust manifold into the turbine housing onto the turbine wheel (Fig. 2). The flow energy of the exhaust gases cause the turbine wheel to rotate. Consequently, the compressor wheel, which is connected through the turbine shaft with the turbine wheel, is driven at the same speed. The fresh air inducted by the compressor wheel is compressed and passed to the engine (Fig. 2).

The charge pressure is controlled by varying the position of the guide vanes (Fig. 2). The guide stud of the control linkage of the boost pressure actuator turns the adjusting ring in the turbine housing (Fig. 2). As a result, all the guide vanes whose guide studs likewise mesh into the adjusting ring, are also turned (Fig. 2).

At low speeds, the flow cross-section is reduced by closing the guide vanes (Fig. 2). Consequently the speed at which the exhaust gas impacts on the turbine wheel is increased, as a result of which the speed of the turbocharger and thus the charge pressure rises.

At high engine speeds the guide vanes are increasingly opened and the flow cross-section is thus enlarged, as a result of which the speed of the turbocharger reduces and the charge pressure drops.