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Funny Car is a type of drag racing vehicle and a specific racing class in organized drag racing. In the United States, the other professional drag racing classes are Top Fuel, Pro Modified, Pro Stock, and Pro Stock Bike. Funny cars are characterized by having tilt-up fiberglass or carbon fiber automotive bodies over a custom fabricated chassis, giving them an appearance vaguely approximating manufacturers' showroom models. They also have forward-mounted engines (engine placed in front of the driver), as opposed to dragsters which (currently) place the engine behind the driver. Funny car bodies typically reflect the models of newly available cars in the time period that the funny car was built. For example, in the 1970s, then current models such as the Chevrolet Vega or Plymouth Barracuda were often represented as funny cars, and the bodies represented the Big Three of General Motors, Ford, and Chrysler. Currently, four manufacturers are represented in National Hot Rod Association (NHRA) Funny Car — Chevrolet with the Camaro, Dodge with the Charger, Ford with the Mustang, and Toyota with the Camry. Worldwide, however, many different body styles are used. These "fake" body shells are not just cosmetic; they serve an important aerodynamic purpose.〔(The Serious Business of Funny Car Aerodynamics ), General Motors〕 ==Guidelines== The NHRA has strict guidelines for funny cars. Most of the rules relate to the engine. In short, the engines can only be V-8s displacing no more than 500 cubic inches (8.19 L). The most popular design is loosely based on the second generation Chrysler 426 Hemi "Elephant Engine" made from 1964 to 1971. There can only be two valves per cylinder. The heads are machined from aluminum billet and have no water jackets, as the high latent heat of the methanol in the fuel coupled with the brevity of the run precludes the need for water cooling of the cylinder heads. Superchargers are restricted to a basic Roots type— rotor case width with a breadth of . The rotors are not allowed to have more than a certain amount of helical twist in them so the blower does not become a screw-type supercharger in function. Only single camshafts are allowed. There are two common bore-stroke combinations: (called a ''3/4 stroker'') and (called a ''5/8 stroker''). The 3/4 stroker is the most common combination used today and equals 496 CID (8.1 L). Crankshafts are CNC machine carved from steel billet then nitrided in an oven to increase surface hardness. Intake valves are titanium and of width, while exhaust valves are width of Inconel. Every funny car has ballistic blankets covering the supercharger because this part of the engine is prone to explosion. Funny car fuel systems are key to their immense power. During a single run (starting, burnout, backing up, staging, 1/4 mile) cars can burn as much as of fuel. The fuel mixture is usually 85–90% nitromethane with 10–15% methanol. The ratio of fuel to air can be as high as 1:1. Compression ratios vary from 6:1 to 7:1. The engines in funny cars commonly exhibit varying piston heights and ratios that are determined by the piston's proximity to the air intake. Funny cars have a fixed gear ratio of 3.20:1 and have a reversing gear; power is transmitted from engine to final drive through a multiple staged clutch which provides progressive incremental lockup as the run proceeds. The rate/degree of lockup is mechanically/pneumatically controlled and preset before each run according to various conditions, in particular track surface. Wheelbase is between . The car must maintain a ground clearance. Horsepower claims vary widely—from 6,978 to 8,897—but are probably around 8,000 HP. Supercharged, nitromethane-fueled motors of this type also have a very high torque, which is estimated at about . They routinely achieve a 6G acceleration from a standing start. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「funny car」の詳細全文を読む スポンサード リンク
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