Engine Performance: System: Turbocharger: Description

Saab uses a Garrett T3 Turbocharger. Exhaust gases drive the turbine, which turns the compressor, pushing air under pressure to the throttle valve.

Excessive pressures are controlled by a boost pressure control valve or wastegate. A pressure switch prevents engine damage in case of wastegate failure. Additional engine protection is provided by the Automatic Performance Control (APC) system. The APC system senses engine knock and automatically cuts back the amount of boost.

The system is designed to operate at low engine speeds, providing increased torque at typical vehicle driving speeds. The turbine shaft is mounted in a floating, sliding-contact bearing having a high oil flow. The shaft actually floats on oil during operation.

Lubrication is supplied by the engine lubrication system. The shaft is sealed against bearing housings with sealing rings installed in shaft grooves. The turbocharger is equipped with an intercooler. The intercooler is located between turbocharger and inlet manifold.