A V4 engine is a four-cylinder piston engine where the cylinders share a common crankshaft and are arranged in a V configuration. V4 engines are much less common than inline-four engines, however V4 engines have been used at times in automobiles, motorcycles and other applications.
Design
Most V4 engines have two crankpins that are shared by opposing cylinders. The crankshaft is usually supported by three main bearings. Compared to the more common inline-four engine layout, the advantages of the V4 include a shorter length and— when a 90-degree V-angle is used with the optimal firing interval— perfect primary balance which reduces vibration. The design can also result in a smaller rocking couple than an inline-four engine, and the shorter crankshaft is less susceptible to the effects of torsional vibration due to its increased stiffness. A disadvantage of V4 engines is that it requires two cylinder heads and exhaust manifolds, which increases cost and complexity. V4 engines are also wider than inline-four engines and it can be more difficult to incorporate ancillaries, inlet systems and exhaust systems while maintaining a compact size. Although a 60-degree V4 engine is more compact than a 90-degree V4 engine, the 60-degree design does not have perfect primary balance and therefore often requires a balance shaft to reduce vibrations.
Automobile use
The earliest automotive use of V4 engines were in Grand Prix racing cars. One of the pioneering V4 engines was in the 1898 Mors rear-engined car built in France.At the time, the lack of vibration from the V4 engine was a key selling point, however by 1901 the V4 engine was replaced by a conventional inline-four engine. In the 1907 French Grand Prix, the car entered by J. Walter Christie used a V4 engine, the largest engine ever used in a Grand Prix race. The engine was mounted transversely in the front and the car was front-wheel drive. The car retired from the French Grand Prix after just four laps, however it later set a speed record of. The first V4 engine used in production cars was the Lancia V4 engine, which was first used in the 1922 Lancia Lambda. The Lancia engine was a narrow-angle design with an angle of 20 degrees between the banks and a single cylinder head with one overhead camshaft shared by both banks. It also used an aluminium construction for both the block and head. Lancia produced V4 engines until 1976, when they were replaced by flat-four engines. The 1960-1994 ZAZ Zaporozhets was a Ukrainian city car which used a rear-mounted V4 engine. This engine— based on the engine used in the LuAZ-967 amphibious militiary vehicle— was air-cooled with a magnesium block and was produced in displacements from. The AMC Air-cooled 108 was a built from 1960-1963 for use in the lightweight M422 Mighty Mite military vehicle. The M422 was by Jeep in the United States and designed to be transported by helicopter. Beginning in the 1960s, Ford's European divisions produced two unrelated V4 engines. The first was the Ford Taunus V4 engine, produced in Germany from 1962–1981. The Taunus was a 60-degree V4 engine with water cooling and overhead valves. Initially designed for use in front-engined cars, it was used in various Ford models and also used in the Saab 95, Saab 96 and Saab Sonett models. It was also used in the mid-engine Matra 530 sports car. The second Ford V4 engine was the Ford Essex V4 engine, produced in the United Kingdom from 1965-1977 and used in several Ford Corsair, Capri, Consul, Zephyr and Transit models. Although designed separately to the Taunus engine, the Essex also was a 60-degree V4 with water cooling, overhead valves and designed for use in front-engined cars/vans. The Porsche 919 Hybrid LMP1 racing car used in the 2014–2017 seasons used a 90-degree turbocharged V4 engine which was mid-mounted.
Motorcycle use
One of the first motorcycles powered by a V4 engine was the 1931-1935 Matchless Silver Hawk built in the United Kingdom. The Silver Hawk used a narrow angle 16-degree V4 engine with a single cylinder head, pushrod valve actuation and air cooling. The 1936-1938 Puch P800 was built in Austria for both civilian and military uses. The P800 used a very wide-angle 170-degree V4 engine with two cylinder heads and air cooling. V4 engines enjoyed particular popularity during the mid-to-late 1980s, especially in transverse-engined Honda motorcycles which had a 90-degree V4 engine with water cooling. The Majority of 2020 MotoGP manufacturers chose the V4 configuration for their bikes.
Yamaha & Suzuki retain the in-line 4 configuration
Other uses
In 1935, the Wisconsin Motor Manufacturing Company began producing petrol V4 engines for industrial, agricultural and stationary applications, with several farm equipment manufacturers using the Wisconsin V4 enginess. In 1968, the largest Wisconsin V4 engine was the V-465D with a displacement of and a power output of at 3000 rpm. The company produced V4 engines until 2019. In the mid-1940s, Turner Manufacturing Co in the United Kingdom produced a diesel water-cooled V4 engine for industrial and marine uses. This engine was used in the 1949-1957 Turner Yeoman of England tractor. Mitsubishi Heavy Industries built the 4ZF, an air-cooled diesel-powered V4 engine used in the Type 73 Armored Personnel Carrier and related Japanese military vehicles since 1973. Another use of the V4 engine is in outboard motors for boats. They are usually two-stroke engines with a carburetor. Some of the largest manufacturers are Johnson, Evinrude, and Yamaha. V4 engines are popular in this application due to their short length.