 This necessitates a process of homologation in which a suitable production road car design is modified within the limits of a formula's technical regulations.Such changes may include modified or entirely new parts in the engine, gearbox, suspension, bodywork and so on.In the Super 1600 formula, "suitable" is defined as a passenger car that has one driven axle (two-wheel drive) and a 4-cylinder engine that is of naturally aspirated configuration with a maximum volume of 1640cc.