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A V8 engine is a V engine with eight cylinders. The V8 is a very common configuration for large automobile engines. V8 engines are rarely less than 3 litres in displacement and in automobile use have gone up
to 8.5 litres or so. American cars until the mid 1970s almost universally
had V8 engines, and many still insist on them.
The normal V-angle for a V8 is 90°. There are two classic types of V8s which differ by crankshaft.
The cross-plane V8 is the typical V8 configuration used in American road cars. Each crank pin (of four) is at a 90° angle from
the previous, so that viewed from the end the crankshaft forms a cross. The cross-plane can achieve very good balance but
requires heavy counterweights on the crankshaft. This makes the cross-plane V8 a slow-revving engine that cannot speed up or slow
down very quickly compared to other designs, because of the greater rotating mass. While the firing of the cross-plane V8 is
regular overall, the firing of each bank is not; this makes designing performance exhaust systems more difficult.
The flat-plane V8 design has crank pins at 180°. They are imperfectly balanced and thus produce severe vibrations. As they
don't require counterweights, the crankshaft has less mass and thus inertia, allowing higher RPM and quicker acceleration.
They're mainly used as racing engines, the most famous example being the Ford-Cosworth DFV.
The Coventry-Climax 1.5
litre V8 evolved from a cross-plane configuration to a flat-plane configuration in its latest versions.
American V8 Engines
The United States can be considered the 'home of the V8' - it has
always been more popular there than anywhere else, and it is certainly even now the preferred arrangement for any large engine.
With the recent exceptions of the Dodge Viper's V10 and the Ford large truck engine of the same
arrangement, there are practically no large engines in the US of post-World War
II design that have not been of this type.
Ford were the first company to use V8s en masse - instead of going to a six-cylinder engine like its competitors when
something larger than a straight-4 was needed, Ford went straight to the V8
with its famous Ford Flathead
V8 of 1932. This engine powered almost all larger Ford cars until 1953, and was produced until around 1970 by Ford licensees around the
world, mostly powering commercial vehicles.
Some other companies followed Ford and built V8s, while others, like Buick, used
straight-8 engines for their larger cars, and straight-6 engines for smaller ones. Postwar, increasing vehicle size meant that the straight-6 became
increasingly underpowered, while the straight-8 was simply too long. This meant that by the 1950s, all American automobile manufacturers had a V8 in their range, powering the majority of the vehicles sold.
A full history of each manufacturer's engines is out of scope in this article, but engine sizes on full-size cars grew
throughout the 1950s, 1960s and into the early to mid 1970s. The increasing size of full-size cars meant that smaller models of car were introduced and became more
popular, with the result that by the 1960s most manufacturers had two V8 models.
The larger engines, known as big-block V8s, were used in the full-size cars. Big-blocks generally had displacements in excess of 6 litres
(360 cubic inches), but in stock form are often not all that efficient. Big-blocks reached displacements of up to 8.2 litres (500
cubic inches) in production form. Once the 1970s oil crisis and pollution regulations hit, big-block V8s didn't last too much
longer in cars; luxury cars lasted the longest, but by 1977 or so they were gone. In
trucks and other larger vehicles, big-block V8s in their historic form lasted until the
early 1990s.
Smaller engines, known as small-block V8s, were fitted in the mid-size car ranges and generally displaced between 4.4 litres (270
cubic inches) and 6 litres (360 cubic inches), though some grew as large as 6.6 litres (400 cubic inches). As can be seen, there
is overlap between big-block and small-block ranges, and an engine between 6 and 6.6 litres could belong to either class. Engines
like this (much evolved, of course) are still in production.
During the 1950s, 60s and 70s, every General Motors division had
their own engines, whose merits varied. This enabled each division to have its own unique engine character, but made for a lot of
wasted duplication of effort. Ford and Chrysler had fewer divisions, and engines tended to be shared across families a lot
more.
See also (American V8s)
- Ford V8s
- Ford Flathead
engine
- Ford Y-block
engine
- Ford FE engine (390, 427, 428)
- Ford 385 engine (429, 460)
- Ford 90
degree V engine (298, 302, 351 Windsor)
- Ford 335 engine (351 Cleveland, 351 Modified, 400)
- Oldsmobile V8s
- Oldsmobile L head engine
- Oldsmobile Viking engine
- Oldsmobile Rocket engine
- Oldsmobile Aurora engine
British V8 engines
The most common British V8 is the Rover
V8, used in countless British performance cars. This is not actually a British design at all but was imported from America,
its roots being in General Motors, Oldsmobile division development of a cast-aluminum block small V8
in the late 1950s. It was of the small (for the US market) size of 3.5 litres (215 cubic inches) and very light for a V8. It
appeared in production in 1961 on some of that year's Buick, Oldsmobile and Pontiac models,
but was soon dropped in favor of more conventional iron-blocked units.
As the aluminium block made this engine one of the lightest stock V8s built there was some attempts to use it in racing at
Indianapolis. The Australian firm Repco converted this engine for Formula One
by reducing it to 3 litres and fitting a single overhead
camshaft per bank rather than the shared pushrod arrangement. Repco-powered Brabhams won the F1 championship twice, in 1966 and 1967.
Rover were in need of a new, more powerful engine in the mid 1960s, and became aware
of this small, lightweight V8. After some negotiation they acquired rights to it and have produced it ever since, its first
appearances being in Rover saloons in the late 1960s.
As well as appearing in Rover cars, the engine was widely sold to small car builders, and has appeared in all kinds of
vehicles. Rover V8s feature in some models from Morgan,
TVR , Triumph and
MG, among many others. They're also the standard British engine in hot rods, much like the Chevrolet 350 small-block is to American builders.
Czech V8 engines
Tatra used air-cooled V8 engines.
German V8 engines
Italian V8 engines
Ferrari
Ferrari have used V8 engines in a number of cars, including the Ferrari 308 and Ferrari 328.
Lamborghini
Lamborghini have always fitted V12s in their top-of-the-line cars, but
have built many V8s for their lower models, including the Urraco and Jalpa
Maserati
Maserati have used V8s for many of their models, including the Maserati Bora.
Spanish V8 engines
Spanish truck company Pegaso made around 100
cars in the 50s and 60s. These cars were powered
by a DOHC 32 valve V8, with up to 360 hp (270 kW).
V8s in Aviation
Hispano-Suiza WW1 V8.
External links
V8® is a trademark name for a brand of beverages
made from juices from eight vegetables, specifically: tomatoes, beets, celery,
carrots, lettuce, parsley, watercress, and spinach. The brand is owned by the Campbell
Soup Company.
The brand is the ancestor of the "V8 Splash" brand, which features drinks made from a blend of fruit juices instead of vegetables.
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