SAAB WIS ONLINE

System overview

System overview


Compared with the engine fitted in Saab 900 and 9000 models, the 4-cylinder engine in the Saab 9-5 has been extensively modified in several respects.

The purpose of the modifications is to reduce fuel consumption, improve emission control efficiency and minimize vibration at low engine rpm.

Some of the more important changes are described below:


• The compression ratio has been raised.

• The valves are lighter and the valve springs softer.

• The cam times have been modified.

• The cylinder head gasket is of sheet metal.

• The connecting rods are longer and the pistons lighter.

• The balancer shafts are lighter and have new chain sprockets.

• The oil pump's overcapacity has been reduced slightly.

• The engine block and timing cover are lighter.

• The flywheel is heavier.


As a result of the above modifications, most of the engine components are completely new. Several repair methods and tightening torques for screw connections are also different to those used earlier. To give an example, the balancer shaft sprockets are now secured by M8 bolts instead of the M10 bolts previously fitted.