this year as the start of the modern era of NASCAR racing. In addition, R.J. Reynolds (the tobacco conglomerate) took over as the major sponsor of NASCAR racing (changing the name to the "Winston Cup") and they made a significantly larger financial contribution than previous sponsors. Richard Petty's personal sponsorship with STP also set new, higher standards for financial rewards to driving teams. The sudden infusion of noticeably larger amounts of money changed the entire nature of the sport. The 1973 oil crisis meant that large displacement special edition homologation cars of all makes were suddenly sitting unsold. Through the balance of the 1970s until 1992, the factory stock sheetmetal over a racing frame meant the cars looked very much like their street version counterparts. It can be said that 1993, with the addition of ground effect wrap-around type spoilers, marked the beginning for non-stock sheetmetal and from that point forward, stock cars were quickly allowed to differ greatly from anything available to the public. Modern racing "stock" cars are stock in name only, using a body template that is vaguely modeled after currently available automobiles. The chassis, running gear, and other equipment have almost nothing to do with anything in ordinary automobiles. NASCAR and the auto manufacturers have become aware of this, and for 2013 each brand (Chevrolet, Dodge, Ford, and Toyota) have redesigned their racing sheetmetal to more resemble the street models of their cars. Types of cars A stock car, in the original sense of the term, is an automobile that has not been modified from its original factory configuration. Later the term stock car came to mean any production-based automobile used in racing. This term is used to differentiate such a car from a "race car", a special, custom-built car designed only for racing purposes. The degree to which the cars conform to standard model specs has changed over the years and varies from country to country. Today most American stock cars may superficially resemble standard American family sedans but are in fact silhouette cars: purpose-built racing machines built to a strict set of regulations governing the car design ensuring that the chassis, suspension, engine, etc. are architecturally identical to those in stock production vehicles. For example, NASCAR Cup Series race vehicles now require fuel injection. In the UK and New Zealand there is a racing formula called stock cars, but the cars are markedly different