in 1991, saab introduced a 2.1-litre naturally aspirated 16 valve version of this engine, with an increased displacement of () and a resulting name of b212. the inlet manifold was enlarged and redesigned for better and greater flow. the intake manifold and the head from the 2.1-litre constitute a well-known replacement for 1985-1993 16 valve, 2.0-litre turbocharged saabs. power increase is modest at stock boost but becomes much more evident at higher boost levels.