V8 engine
A V8 engine is an eight-cylinder piston engine in which two banks of four cylinders share a common crankshaft and are arranged in a V configuration.
Origins
The first known V8 was the Antoinette, designed by Léon Levavasseur, and built in 1904 by the French Antoinette company for use in speedboat racing, cars, and later, airplanes.Also in 1904, V8 engines began small-scale production by Renault and Buchet for use in race cars.
Design
V-angle
Most engines use a V-angle of 90 degrees. This angle results in good engine balance, which results in low vibrations. However, the downside is the greater width of the engine compared to those that use a smaller V-angle.V8 engines with a 60-degree V-angle were used in the 1996–1999 Ford Taurus SHO, the 2005–2011 Volvo XC90, and the 2006–2009 Volvo S80. The Ford engine used a 60-degree V-angle because it was based on a V6 engine with a 60-degree V-angle. Both the Ford and Volvo engines were used in transverse engine chassis, which were designed for a front-wheel-drive layout. To reduce the vibrations caused by the unbalanced 60-degree V-angle, the Volvo engines used a balance shaft and offset split crankpins. The Rolls-Royce Meteorite tank engine also used a 60-degree V-angle, since it was derived from the 60 degree V12 Rolls-Royce Meteor which in turn was based on the Rolls-Royce Merlin V12 engine.
Other V-angles have been used occasionally. The Lancia Trikappa, Lancia Dilambda, and Lancia Astura, produced 1922–1939, used narrow angle V8 engines with V-angles of degrees. The 1932 Miller four-wheel drive racing cars used a V8 engine with a V-angle of 45 degrees. The 8-cylinder versions of the 1945 through 1966 EMD 567 diesel locomotive engine also used a V-angle of 45 degrees.
Crankshaft configuration
Cross-plane crankshaft
Most V8 engines fitted to road cars use a cross-plane crankshaft since this configuration produces less vibration due to the perfect primary balance and secondary balance. The cross-plane crankshaft has the four crank pins at angles of 0, 90, 270, and 180 degrees, which results in a cross shape for the crankshaft when it is viewed from one end.The rumbling exhaust sound produced by a typical cross-plane V8 engine is partly due to the uneven firing order within each of the two banks of four cylinders. A usual firing order of L-R-L-L-R-L-R-R results in uneven intake and exhaust pulse spacing for each bank. When separate exhaust systems are used for each bank of cylinders, this uneven pulsing results in the rumbling sound typically associated with V8 engines. However, racing engines seek to avoid these uneven exhaust pressure pulses to maximize the power output. The 1960s cross-plane V8 racing engines used long primary exhaust pipes or located the exhaust ports on the inside of the V-angle.
Flat-plane crankshaft
A flat-plane crankshaft configuration provides two benefits. Mechanically, the crankshaft can be machined from a flat billet and does not require counterweights so it is lighter. However, it produces more vibration due to a secondary imbalance. Most early V8 road car engines also used a flat-plane crankshaft since this was simpler to design and build than a cross-plane crankshaft. Early flat-plane V8 engines included the 1910 De Dion-Bouton engine, the 1915 Peerless engine, and the 1915 Cadillac engine. A flat-plane crankshaft is used by many V8 engines fitted to racing cars.From the gas dynamics aspect, the flat-plane crankshaft allows for even exhaust gas pulses to be achieved with a simple exhaust system. The design was popularized in motor racing by the 1961–1965 Coventry Climax FWMV Formula One engine, and the 1967–1985 Cosworth DFV engine was highly successful in Formula One. Several production sports cars have used flat-plane V8 engines, such as every Ferrari V8 model, the Lotus Esprit V8, the Porsche 918 Spyder, and the McLaren MP4-12C.
Automobile use
The first V8 engine used in a road-going car was the 1905 Rolls-Royce built in the United Kingdom. This model was initially equipped with a V8 engine. However, only three cars were made before Rolls-Royce reverted to using straight-six engines for their cars.In 1907, the Hewitt Touring Car became the first car built in the United States with a V8 engine. The engine was designed and built by Edward R. Hewitt who emphasized the V8's superiority to the typical I4 and I6 and six-cylinder engines of the time because of its lower weight and easier to make crankshaft compared to the I6s of equal power as well as the V8 not taking much more space than a I4.
The 1910 De Dion-Bouton— built in France— is considered to be the first V8 engine produced in significant quantities.
The 1914 Cadillac L-head V8 engine is considered the first road-going V8 engine to be mass-produced in significant quantities, with 13,000 sold the first year. This engine was built in the United States and was greatly assisted by Cadillac's pioneering use of electric starter motors.
The popularity of V8 engines in cars was significantly increased following the 1932 introduction of the Ford Flathead V8.
By the early 21st century, the use of V8 engines in passenger vehicles declined as automobile manufacturers opted for more fuel efficient, lower capacity engines, or hybrid and electric drivetrains.
Size, layout, and classification
The displacement of modern V8 engines is typically from. However, size of production engines varies widely - for example the BMW M502 V8 introduced in the 1954 BMW 502 displaced only, while the 1971-1978 Cadillac Eldorado was powered by an motor. V8 engines intended for motorsport are often small and short-stroke to maximize RPMs and thus power. The Cosworth DFV is an example.Due to its large external dimensions, V8 engines are typically used in cars that use a longitudinal engine layout and rear-wheel drive. However, V8 engines have also occasionally been used in transverse engine front-wheel drive vehicles, sometimes using closer cylinder bore spacings and narrower cylinder bank angles to reduce their space requirements.
The classification of 'big-block' or 'small-block' refers to the engine's external dimensions and does not necessarily indicate the actual engine displacement. Engines with displacements from have been classified as both small-block and big-block, depending on the particular manufacturer's range of engines.
Motorsport
V8 engines have been used in many forms of motorsport, from Formula One, IndyCar, NASCAR, DTM and V8 Supercars circuit racing, to Top Fuel drag racing.Among the first V8 Formula One cars to compete were the 1952 AFM entry and the 1954 Lancia D50, with a development of the latter powering Juan Manuel Fangio's 1956 car to victory in the driver's championship. The 1.5 L Formula One era of 1961–1965 included V8 engines from Ferrari, Coventry Climax, British Racing Motors, and Automobili Turismo e Sport. The driver's championships for the 1962, 1963, 1964, and 1965 seasons were won by drivers of V8-powered cars.From 1962 through 1965, the top three manufacturers in each season's Constructor's Championship all predominantly used V8 engines in their cars. In 1966, the engine capacity limits were increased to , and both the 1966 and 1967 Constructor's Championships were won by cars powered by the Repco-Brabham V8 engine.
From 1968 until 1981, the Cosworth DFV V8 engine dominated Formula One racing. During this time, the Manufacturers' Championship was won by Cosworth DFV-powered cars every season except 1975, 1976, 1977, and 1979, which 12-cylinder Ferraris won. After a long period of dominance, the Cosworth DFV was eventually outpaced by turbocharged straight-four and V6 engines.
The next period of significant V8 usage in Formula One was from 2006 to 2013, when the rules mandated use of naturally-aspirated V8 engines, with regular power outputs between 730 and 810 hp. These were replaced by 1.6 litre turbocharged V6 engines for the 2014 and later seasons.V8 engines have dominated American premier stock car racing NASCAR series since its inaugural 1949 season. However, there wasn't a strict ruleset to follow until the 1972 season, when engines were no longer allowed to be any bigger than for the purpose of reducing speeds caused by the rapid aerodynamic advancements from 1969 to 1971.In the American Top Fuel class of drag racing, V8 engines displacing today produce outputs of over. and. The engines used in Top Fuel and Funny car drag racing are typically based on the aluminium-conversion Chrysler 426 Hemi engine and run on highly explosive nitromethane fuel.The world's fastest non-jet-powered wheeled land vehicle, the Speed Demon, which achieved a speed of in 2017, is powered by a V8 engine based on the Chevrolet small-block engine design.
Automobile use by country
Australia
The first Australian-designed car to use a V8 engine was the 1965 Chrysler Valiant, which was available with an American-built Chrysler engine. The first locally designed V8 Ford was the 1966 Ford Falcon and the first V8 Holden was the 1968 Holden HK, both using engines supplied by their parent companies in the United States.The first V8 engine to be mass-produced in Australia was the 1969–2000 Holden V8 engine. This cast-iron overhead valve engine used a V-angle of 90 degrees and was built in displacements of and, the latter being de-stroked to in 1985. The Holden V8 engine was used in various models, including the Kingswood, Monaro, Torana, Commodore, and Statesman. Versions tuned for higher performance were sold by Holden Dealer Team and Holden Special Vehicles, including versions stroked to up to. The Holden V8 engine was also used in touring car racing and formed the basis of the Repco-Holden engine used in Formula 5000 racing. In 1999, the Holden V8 engine began to be replaced by the imported General Motors LS1 V8 engine.
In 1971, Ford Australia began local production of the Ford 'Cleveland' V8, an overhead valve cast-iron engine. The engine was produced in displacements of and for use in the Australian Ford Falcon and Ford Fairlane models. It was also used in several low-volume DeTomaso sports cars and luxury sedans built in Italy. Australian production ceased in 1982 when Ford Australia temporarily stopped production of V8 cars. From 1991 until 2016, the Ford Falcon was available with the imported Ford Windsor, Ford Barra, or Ford Modular V8 engines; the latter was marketed as "Boss" and locally assembled from a mix of imported and local parts.
A version of the Rover V8 engine was produced in Australia for the ill-fated 1973–1975 Leyland P76 sedan. The engine had an overhead valve design and was the only all-aluminum engine made in Australia.