SEDAN The sedan is the most common configuration of a modern automobile. Sedans usually have four doors, although the term can be used to describe a two-door body also. Most of them have a three-box configuration, but two-box bodies are also common, mostly in Europe. SEMI ELLIPTIC MULTI LEAF SPRINGS Usually found on trucks and sport utility vehicles, this type of springs consists of arched steel leafs that are stacked together horizontally to form the foundation of the rear suspension. SEQUENTIAL TURBOCHARGERS Sequential turbochargers were created from the need to decrease spooling lag. Two or sometimes more turbochargers are put to work in sequence. Usually, a smaller one begins working at low rpms and the other(s) at higher rpms, thus improving the power delivery throughout the power curve, not only above a certain number of revs. SHIFT-ON-THE-FLY Most part-time four-wheel drive systems in the past required their dri...