the b205 and b235 engines are an evolution of the b204 and b234 engines. they were introduced in the 1998 saab 9-5 giving reduced fuel consumption and emissions with improved refinement. the changes included lightweight internal components:lighter valves, softer valve springs, lighter pistons, and lower-drag oil pump. another development was the introduction of the trionic 7 torque demand type engine management system. trionic 7 equipped engines have the black direct ignition casing on top of the engine rather than the red of the trionic 5.