Champ Car Racing
A Champ Car is a single-seat racing car, quite similar to Formula One racing cars.
Champ Cars race in high speed oval tracks. The increased stress and speed of these tracks mean that racing cars tended to be heavier and have longer wheelbases than F1 cars to increase stability. However, this decreases agility.
A Champ Car weighs over 30% more than a Formula One Car, with the weight of the driver factored in.
The minimum weight for a Champ Car is adjusted from 1,575 lbs based on the weight of the driver compared to the field average; with the driver included, all cars have a minimum weight of 1741 lbs.
For example, a Champ Car driven by 195lb Paul Tracy (the heaviest driver in the series and 29 lbs heavier than the field average) must weigh at least 1,546 lbs when empty.
The minimum weight of a Formula One Car, including the driver, is 605 kg (1,334 lbs). This difference of 407 lbs (184.6 kg) is just over 30% of the F1 car's weight.
Since the late 1960s Champ Cars have used turbocharged engines. Turbos were banned in Formula One on safety grounds in 1989.
For some periods of their history, notably in the early 1970s and late 1990s, turbocharging gave Champ Cars up to 300 horsepower (220 kW) more than F1 cars.
Recently in 1999/2000 the Champ Cars approached 1,000 horsepower (750 kW) before regulations on turbo boost were tightened. The current generation of cars have less power than F1 cars, Champ Cars having 700 hp and F1 cars having 850 hp (since F1 switched to V8 engines for the 2006 season), with the turbo used mainly to improve the spectacle rather than lap-times with the so-called 'power-to-pass' or 'push-to-pass' system giving drivers an increased amount of power for a limited duration during the race.
Another reason for retaining the turbocharger is the muffling effect it has on the exhaust note helps keep the cars inside noise-limits, particularly at the many city street races on the schedule.
Champ Cars use methanol for fuel rather than gasoline, and refueling has always been permitted during the race. This is a legacy of a crash at the 1964 Indianapolis 500 in which a crash involving cars filled with more than 75 US gallons (285 L) of gasoline killed Dave MacDonald and Eddie Sachs. Until 1994, when refueling was re-introduced to F1, the coupling for the refueling hose was a notable difference between Champ Cars and Formula cars.
Champ Cars continue to have sculpted undersides to create ground effect. This innovation was originally created in Formula One by Lotus in 1978, and was immediately used on the Chaparral Champ Car in 1979.
F1 banned sculpted undersides in a bid to lower cornering speeds for 1983. In an effort to create better passing opportunities, the new spec Champ Car chassis being introduced in 2007 will generate nearly 50% of the total downforce of the car with sculpted underside tunnels versus the front and rear wings. This will reduce turbulent air behind the cars, enabling easier overtaking.
While F1 use grooved tires to limit performance, Champ Cars remain using tread-less "slick" racing tires. To make races more unpredictable, drivers are permitted to use one set of higher performance softer compound "alternate" tires known as "reds", as these tires are made visible to the spectators by their red sidewalls.
Unlike in F1, Champ Car teams are not obliged to construct their own chassis, and in recent times have tended to buy chassis constructed by independent suppliers such as Lola, Swift, Reynard, March and Dan Gurney's Eagle.
The most notable exception was Penske Racing, although they also bought other cars when their own chassis was uncompetitive. Starting in 2007, Champ Car will feature only a single, "spec" chassis, the DP-01, created by Elan Technologies, a racing equipment manufacturer owned by Don Panoz.
The spec chassis was introduced to reduce costs for race teams, however Champ Car had essentially been a spec series since 2004, with all teams favoring the Lola chassis.