Complex sentence: From September 1972 the 1985 cc Saab B engine was used; during the lifetime of the 99 model, several subsequent engine developments took place including the incorporation of fuel injection for some versions.
Split into simpler sentences: From September 1972 the 1985 cc Saab B engine was used. During the lifetime of the 99 model, several subsequent engine developments took place, including the incorporation of fuel injection for some versions.