Engineering:V4 engine

Ford Taunus V4 engine in Saab Sonett III

A V4 engine is a four-cylinder engine with its cylinders arranged in a "V" configuration.

The V4 configuration has seen use in automobiles, motorcycles, marine propulsion, and for industrial/commercial applications.

V4 engine design

Conceptually, a V4 is a pair of V-twin engines mounted end-to-end. Most V4 designs support the crankshaft with three main bearings and have two crankpins that are shared by opposing cylinders. Odd-numbered cylinders are usually in one bank and even-numbered cylinders in the opposite bank. An exception is the V4 in Honda's VFR1200 motorcycle, which has cylinders 1 and 4 in one bank and 2 and 3 in the other bank.

Compared to an inline-four engine, the advantages of the V4 include compactness, short length along the crankshaft, and with a 90° V-angle, perfect primary balance giving smooth operation. A V4 produces less rocking couple than an inline-four of the same bore and stroke. Also, the V4's short crankshaft is stiffer than an inline-four's crankshaft, making the former less susceptible to the effects of torsional vibration.

A disadvantage is that, as with a V-twin, it is more difficult to locate ancillaries, inlet systems, and exhaust systems. A V4 is usually more expensive to produce than an equivalent in-line four, having two cylinder heads and exhaust manifolds, and thus four distinct parts where an inline engine would have two. The compact 60° V4 is not perfectly smooth and needs a balance shaft. In modern times, the V4's advantages have made it particularly suitable for motorcycles and outboard engines. However, the V4's advantages for mass produced vehicle applications do not overcome the additional costs. The engine's layout requires manufacturing two cylinder heads and exhaust manifolds rather than only one each for a I4. Access for maintenance can also become more difficult.

Automobile use

One of the earliest V4 internal combustion engines was that designed by Émile Mors of Paris to power his motor-car of 1897. The 90 degree V-angle with central camshaft and spark ignition meant its layout is much like more modern engines, though in this case the inlet valves were operated by suction alone. At the time the lack of vibration from this layout was a key selling point.

In 1907, J. Walter Christie was the first American to compete in the French GP with his car powered by a 19,891 cc (1,214 cu in) V4, the largest engine ever used in a Grand Prix race.

The V4 engine has not been widely used in cars. AMC, Ford, Lancia, and ZAZ were the only companies to manufacture such an engine.

Lancia produced several narrow-angle V4 engines from the early 1920 through the 1960s for cars like the Lambda, Augusta, Artena, Aprilia, Ardea, Appia, and Fulvia.

From 1960 to 1963, American Motors Corporation (AMC) produced a 108 cu in (1.8 L) air-cooled V4 engine that was used in AMC's lightweight aluminium-bodied M422 'Mighty Mite' military vehicle, as an air transportable (by the helicopters of the time) Jeep for the United States Marine Corps. This engine was not designed for civilian passenger car use.

Ford of Europe produced two totally different V4 engines (with four crankpins) and a balance shaft, one in the UK and one in Germany:

• The British Ford Essex V4 engine, mainly used in the Ford Transit and the Corsair
• The German Ford Taunus V4 engine, also used by Saab, the Matra 530, and in the 1962 Ford Mustang I rear-engine concept roadster)

The Ukrainian manufacturer ZAZ used an air-cooled V4 with a balance shaft, produced by MeMZ and used in Zaporozhets and LuAZ cars.

In 2014, Porsche announced that their 919 Hybrid Le Mans Prototype would use a small-capacity, turbocharged V4 engine.

Variable displacement

In modern cars with V8 engines and variable displacement technology, the engine will enter "V4 mode" during light load conditions such as highway cruising. This technology is known as Active Fuel Management in the Chevrolet Corvette and Multi-Displacement System in the Dodge Challenger.

Motorcycle use

Cutaway view of the V4 engine of a Yamaha V-Max

Longitudinal V4 engine in a Honda ST1100 with its fairing removed

In the 1930s, the Matchless Silver Hawk used a narrow-angle V4, while Puch used a very wide-angle V4. V4 engines are more recently found in motorcycles, typically transversely mounted. This engine design enjoyed particular popularity during the mid-to-late 1980s, especially in Honda motorcycles. Models with V4 engines include:

• Aprilia RSV4
• Aprilia Tuono V4
• Ducati Apollo
• Ducati Desmosedici
• Ducati Panigale V4
• Honda CTX1300
• Honda Sabre
• Honda Magna
• Honda Interceptor VF500F
• Honda Interceptor VF750F
• Honda Interceptor VF1000F
• Honda VF1000R
• Honda VFR750R RC30
• Honda VFR800 Interceptor
• Honda RVF750 RC45
• Honda NR
• Honda RC212V
• Honda ST1100 and ST1300 (Pan-European) with longitudinal engines
• Honda VFR400R
• Honda VFR750F
• Honda VFR1200F
• Motus MST with a longitudinal engine
• Suzuki GV1400 Cavalcade
• Suzuki Madura
• Suzuki GSV-R
• Suzuki RGV500
• Yamaha Venture and Venture Royale
• Yamaha Royal Star and Royal Star Venture
• Yamaha V-Max and VMAX
• Yamaha YZR500

Other uses

Wisconsin Motor Manufacturing Company began producing air-cooled engines in 1929, and added a V4 design in 1935. The company discontinued its water-cooled versions by 1939, and manufactured only air-cooled V4 petrol (gasoline) engines in various displacements for industrial, agricultural, and stationary applications. Farm equipment manufacturers sourced Wisconsin V4s as they offered compact size and good power output. In 1968, the largest in the Wisconsin gasoline line was the new V-465D, a 177 cu in (2.9 L) V4 rated at 65.9 hp (49 kW; 67 PS) at 3000 rpm. Standard features include controlled pressurized lubrication to provide full-time oiling to all working parts, as well as automatic protection against overheating. Wisconsin Motors continues to produce V4 engines for specialized applications.

Turner Manufacturing Co (Wolverhampton, England) developed a V4 water-cooled diesel engine in the mid-1940s for a variety of industrial and marine uses, and used it in their own "Yeoman of England" agricultural tractor from 1949 to 1957.

Another use of the V4 engine is in outboard motors. They are two-stroke cycle and generally carbureted. Some of the largest manufacturers are Johnson, Evinrude, and Yamaha. This type of engine is popular because of its small size, while still producing 140 hp (104 kW; 142 PS), or more.