Complex sentence: Carried over from the previous year were seven available rear axle ratios ranging from 2.73 to 4.56, and the optional Positraction rear axle (mandated on many engine/gearbox combinations) was installed on more than 95% of the cars.
Split into simpler sentences: Carried over from the previous year were seven available rear axle ratios ranging from 2.73 to 4.56. The optional Positraction rear axle, mandated on many engine/gearbox combinations, was installed on more than 95% of the cars.