A V16 engine is a V engine with 16 cylinders. Engines of this number of cylinders are uncommon in automotive use.

A V16 engine is perfectly balanced regardless of the V angle without requiring counter-rotating balancing shafts which are necessary to balance Straight-4 and odd number of cylinder inline engines or counterweighted crankshaft like the 90° V8. In addition angles of 45° and 135° vees give an impulse every 45°, so are optimal solutions, for even-firing and non-split bearing crankshaft journals.

V16 engines are rarely used in automobiles because V8s or V12s of the same displacement produce just as much power, but are much less expensive to manufacture and maintain. The few V16s that have been produced were used in high-end luxury and high-performance automobiles due to their smoothness (low vibration).

Today, the most common applications for V16 engines are railroad locomotives, marine craft, and stationary power generators.

Automotive history

Howard Marmon had begun working on the world's first automotive V16 engine in 1927, but was unable to complete the production 'Sixteen' model until 1931. By that time, Cadillac had already introduced their V16, designed by ex-Marmon engineer Owen Nacker. Peerless, too, was developing a V16 with help from another ex-Marmon engineer, James Bohannon.

The Series 452 was the most exclusive model of the marque from January 1930 until 1940, with this type of engine. Two varieties were built. From 1930 to 1937, Cadillac used a 452 CID (7.4 L), OHV motor with a 45° V. For 1938, a new 431 CID (7.1 L) design was introduced for the Series 90, with a flathead valvetrain and an angle of 135°; this resulted in a much lower cowl height. The 431 was in many ways a superior engine, producing as much power as its immediate predecessor while being far less complex, had a stiffer crankshaft which aided durability and smoothness, and even had an external oil filter, a rarity for any car at any price in those days. However, it was never as popular or highly regarded as its 452 CID predecessor.

By contrast, the Marmon Sixteen was a 45° engine made almost entirely of aluminium. Like modern engines, it used pressed steel cylinder liners. Just 400 Marmon Sixteens were produced between 1931 and 1933.

In 1988, a joint business venture between Claudio Zampolli and musician Giorgio Moroder produced the Cizeta-Moroder V16T which featured a 16-cylinder engine in a unique configuration, but which was not a true V16. Rather, the engine was made up of two flat plane V8s, mounted transversely, with gearing between the two providing a single output from the center of the engine assembly to the longitudinal transmission. It began production in 1991 but only a few cars were produced before the company closed its doors for good.

Cadillac revived the V16 concept in 2003 with a General Motors concept car, the Cadillac Sixteen. This car used a 1,000 hp (750 kW) OHV V16.

BMW also experimented with a V-16, eventually showing a 9-litre (~550 CID) version in the Rolls-Royce 100EX concept car, but it has been changed to a V12 for production due to the customer feedback. However, one of the Rolls-Royce Phantom Coupés which featured in the film Johnny English Reborn is powered by this V-16 engine. That was not BMW's first foray into V-16: BMW had conceived the Project Goldfish, adding four cylinders to the BMW M70 V-12 motor. The BMW Goldfish V16 motor had the displacement of 6.7-litre (414 CID), putting out about 408 hp (304 kW) and 637 N·m (470 lb·ft). That motor was also trialled in new Bentley Mulsanne in the early 1990s.

Racing

The first known use of a V16 in auto racing was by Harry Miller installing a custom-built V16 that he had built for a Cord "supercar" he had been working on into a chassis that he had built for the 1931 Indianapolis 500 driven by Shorty Cantlon. The car was competitive, charging from 26th on the grid to 3rd, but was slowed by unreliability, further exacerbated by having to change all sixteen spark plugs. Bryan Saulpaugh qualified the car third for the 1932 Indianapolis 500, but the car suffered a broken oil line on lap 55 and their race was over. Shortly after the race the V16 was removed and replaced with a conventional Miller four-cylinder. The car was re-assembled and rebuilt with an exact replica V16 in 1993.

The V16 was used in Grand Prix by the mid-engined Auto Union racing cars that rivalled the Mercedes from 1933 to 1938.

Alfa Romeo made two cars with V16 engine the Tipo 162 (135° V16) and Tipo 316 (60° V16). The first one was prototype and the 316 was used on 1938 Tripoli Grand Prix. The 135° engine was engineered by Wifredo Ricart and gave 490 bhp (370 kW) at 7800 rpm, specific output was said to be 164 bhp (122 kW) per litre.

It has only been used once in the post-WWII era, by British Racing Motors (BRM). Most unusually, this was a 135° V 1.5 L (90.8 cu in) supercharged engine. It was a failure despite being powerful. Officially, it produced 550 hp (410 kW) but probably delivered around 600 hp (450 kW).

The BRM V16 delivered this power in a narrow, very lofty, RPM range. This made the car difficult to handle (but the sound made by the 16 small cylinders has been described as 'unforgettable'). The problem was caused by the supercharging system adopted. For expediency BRM chose it to be designed by Rolls-Royce, drawing on their experience of centrifugal superchargers for aircraft engines. Centrifugal superchargers are much more efficient than the more conspicuous Roots type, but they deliver high pressure only at high RPM.

A V12 engine is a V engine with 12 cylinders mounted on the crankcase in two banks of six cylinders, usually but not always at a 60° angle to each other, with all 12 pistons driving a common crankshaft.

Since each cylinder bank is essentially a straight-6, this configuration has perfect primary and secondary balance no matter which V angle is used and therefore needs no balance shafts. A V12 with two banks of six cylinders angled at 60°, 120° or 180° (with the latter configuration usually referred to as a flat-12) from each other has even firing with power pulses delivered twice as often per revolution as a straight-6. This allows for great refinement in a luxury car. In a racing car, the rotating parts can be made much lighter and thus more responsive, since there is no need to use counterweights on the crankshaft as is needed in a 90° V8 and less need for the inertial mass in a flywheel to smooth out the power delivery. In a large displacement, heavy-duty engine, a V12 can run slower than smaller engines, prolonging engine life.

 Early (pre WW1) V12 engines

Motor car engines

In October 1913 Louis Coatalen, chief engineer of the Sunbeam car company entered a V12 powered car in the Brooklands short and long handicap races. The engine displaced 9,048 cc, with bore and stroke of 80 x 150 mm. An aluminium crankcase carried two blocks of three cylinders along each side, with a 60 degree included angle. The cylinders were of iron, with integral cylinder heads with L-shaped combustion chambers. Inlet and exhaust valves were operated by a central camshaft in the vee. Valve clearance was set by grinding the relevant parts, the engine lacking any easy means of adjustment. This pointed to Coatalen’s ultimate aim of using the new V12 as an aero engine, where any adjustment method that could go wrong in flight was to be avoided. As initially built the V12 was rated at 200 bhp (150 kW) at 2,400 rpm, weighing about 750 pounds (340 kg). The engine powered the car (named ‘Toodles V’ (for Coatalen’s wife Olive’s pet name) to several records in 1913 and 1914.

V12 road cars

In automobiles, V12 engines have not been common due to their complexity and cost. They are used almost exclusively in expensive sports and luxury cars because of their power, smoother operation and distinctive sound.

Prior to World War II, 12-cylinder engines were found in many luxury models, including cars from: Packard 1916 to 1923, Daimler 1926 to 1937, Hispano-Suiza 1931, Cadillac 1931, Auburn 1932, Franklin 1932, Lincoln 1932, Rolls-Royce 1936, and Pierce-Arrow also 1936.

Until the general adoption of vibration isolating engine mounts in the 1930s, vehicles with 8-, 12-, and 16-cylinders provided higher levels of refinement.

Packard's 1916 "Twin Six" is widely regarded as the first production V12 engine. With a list price of US$1,000, the Auburn was the lowest priced V12 car ever (unadjusted for inflation). Production cost savings were achieved by using horizontal valves which, however, did not result in an efficient and powerful combustion chamber. Between 1916 and 1921, there was a vogue of V12s, during which National (Indianapolis) copied the Packard engine, and Weidely Motors (also of Indianapolis) offered a proprietary engine. Soon after the end of World War I, Lancia offered a 22° V12, Fiat had a 60° model 520 (1921-2), British truck manufacturer Ensign announced a V12 that did not materialize, and in 1926, Daimler (Britain) offered the first of a full range of sleeve valve Double Sixes, 7,136 cc, 3,744 cc, 5,296 cc and 6,511 cc versions remaining available until 1937 In 1927 more entered the market from, Cadillac, Franklin, Hispano-Suiza, Horch, Lagonda, Maybach, Packard, Rolls, Tatra, Voisin, and Walter offering V12 engines. Cadillac (from 1930 to 1940) and Marmon (1931–1933) even developed V16 engines.

Improvements in combustion chamber design and piston form enabled lighter V8 engines to surpass the V12 in power starting from the 1930s; only the smaller, H-Series Lincoln V-12 remained after WWII and it was replaced by a V8 in 1949. Similarly, as they seemed excessive for the postwar market in Europe, production of V12-engined-cars was very limited until the 1960s.

Ferrari has traditionally reserved their top V12 engine for their top-of-the line luxury sports coupes since 1949. Ferrari's closest rival, Lamborghini has also used the V12 configuration for many of its road cars since the company's inception in 1963. In 1972, Jaguar came out with the XJ12, equipped with a 5.3 litre V12, which continued (after revisions in 1993) until the 1996 model year, after which the marque discontinued the twelve-cylinder engine.

German manufacturer BMW returned to V12 designs for its 7-Series sedan in model year 1986, forcing Mercedes-Benz to follow suit in 1991. While BMW sells far fewer V12-engined 7-Series vehicles than V8 versions, the V12 retains popularity in the US, China, and Russia, as well as maintaining the marque's prestige in the luxury vehicle market segmentThe BMW-designed V12 also appears in Rolls-Royce cars, while the Mercedes engine is also seen in Maybach cars. In their full-sized sedans sold in Canada and the USA, Mercedes and BMW have mid-displacement V8s for the entry-level trims, while having the V12 as the flagship vehicle of the brand.For their most expensive Mercedes-Benz nameplates (S-Class, CL-Class, and SL-Class), there are V8-engined AMG models (55, 63) that have comparable power to their V12-powered cars (600).

In 1997, Toyota equipped their Century Limousine with a 5.0 L DOHC V12 (model # 1GZ-FE), making it the first and only Japanese production passenger car so equipped.

TVR made and tested a 7.7 L V12 called the Speed Twelve, but the project was scrapped after the car it was designed for was deemed too powerful for practical use. The only British marques currently using a V12 configuration are Aston Martin — whose Cosworth-developed engine was authorized during the company's ownership by Ford Motor Company — and Rolls-Royce.

In 2009, China FAW Group Corporation equipped their Hongqi HQE with a 6.0 L DOHC V12 (model # CA12VG), making it the first and only Chinese production passenger car so equipped.

Most production V12 engines in road cars have an even firing order, with the uneven-firing exceptions such as Aston Martin 5.9L V12 and Mercedes-Benz M275 AMG V12s.

In 2008 Audi launched their Q7 model with a 5.9-litre V12 twin-turbo diesel engine, making it the first production passenger car so equipped. The engine also appeared in the R8 V12 TDI concept car.

Heavy trucks

Tatra used a 17.6 L (1,070 cu in) air-cooled naturally aspirated V12 diesel engine in many of their trucks; for instance, the Tatra T813 and uses 19 L air-cooled naturally aspirated or turbo V12 diesel engine in Tatra T815. Some large trucks have been fitted with twin V12s that drive a common shaft, although this is often advertised as a V24.

GMC produced a large gasoline-burning V12 from 1960 to 1965 for trucks, the "Twin-Six"; it was basically GMC's large-capacity truck 351 V6, doubled, with four rocker covers and four exhaust manifolds. Fifty-six major parts are interchangeable between the Twin-Six and all other GMC V6 engines to provide greater parts availability and standardization. Its engine displacement was 702 cu in (11.50 L), and while power was not too impressive at 250 hp (190 kW), torque was 585 lb·ft (793 N·m). For firetrucks the rev limiter was increased to produce 299 hp (223 kW) at 3000 rpm and torque was increased to 630 lb·ft (850 N·m) at 1600-1900 rpm. It was possibly the last gasoline engine used in heavy trucks in the U.S.

Detroit Diesel produced their Series 53, 71, 92, and 149 engines as V-12s, among other configurations.

Auto racing

V12 engines used to be common in Formula One and endurance racing. From 1965 to 1980, Ferrari, Weslake, Honda, BRM, Maserati, Matra, Delahaye, Peugeot, Delage, Alfa Romeo, Lamborghini and Tecno used 12-cylinder engines in Formula One, either V12 or Flat-12, but the Ford (Cosworth) V8 had a slightly better power-to-weight ratio and less fuel consumption, thus it was more successful despite being less powerful than the best V12s. During the same era, V12 engines were superior to V8s in endurance racing, reduced vibrations giving better reliability. In the 1990s, Renault V10 engines proved their superiority against the Ferrari and Honda V12s and the Ford V8. The last V12 engine used in Formula One was the Ferrari 044, on the Ferrari 412T2 cars driven by Jean Alesi and Gerhard Berger in 1995.

In the late 1960s Nissan used a V12 in the Japanese Grand Prix and again in the early 1990s Group C races.

At the Paris motor show 2006 Peugeot presented a new racing car, as well as a luxury saloon concept car, both called 908 HDi FAP and 908 RC and fitted with a V12 Diesel engine producing around or even surpassing 700 PS (515 kW; 690 hp). This took part in the 24 Hours of Le Mans 2007 race, with a podium finish and very competitive performance, coming in second place after the similarly conceived Audi R10 TDI V12 Diesel originally developed for the 2006 season. 

Tanks and other AFVs

The V12 is a common configuration for tank and other armoured fighting vehicles (AFVs). Some examples are:

• German Maybach HL120TRM gasoline engine, used on World War II Pz Kpfw III and Pz Kpfw IV tanks.
• British Rolls-Royce Meteor gasoline engine, derived from the Merlin aero-engine, used on World War II Cromwell and Comet tanks and the post-WWII Centurion and Conqueror tanks.
• Russian V-2 (В-2) V-12 diesel engine, used on World War II T-34, KV-1, KV-2 and IS-2 tanks. Most modern Russian diesel engines for MBT's goes back to V-2 base design.
• American Continental AV1790 engine, produced in gasoline and diesel variants, used on all versions of the Patton tank and on the M103 heavy tank. One of these engines was used to power a hot rod style car called the Blastolene Special.
• The 26.6 litre Perkins diesel engine in the Challenger 2 main battle tank and its variants.

Mechanics

The V10 is essentially the result of mating two even-firing straight-5 engines together. The straight-5 engine shows first and second order rocking motion. Here it should be assumed that the crankshaft with low second-order vibration is used and the first order is balanced by a balance shaft. By mating the straight-5 banks at 90 degrees and using five throws the balance shafts balance each other and become null. The firing sequence is odd (BMW S85, Dodge Viper, Ford 6.8 and 6.4 V10 , Volkswagen Touareg). Using an 18° split journal crankshaft the firing order can be made even, and the two balanced shaft do not balance each other completely, but are combined into a single very small balance shaft (Lamborghini V10, Porsche Carrera GT). Using a five-throw crankshaft and 72° bank angle the firing order can be made even, and the two balanced shafts do not balance each other completely, but are combined into a single small balance shaft (Toyota 1LR-GUE engine). A 36° degree bank angle and a 108° flying arm crankshaft would allow even firing without a balance shaft and smaller counterweights, but would be impractical.

The V10 configuration is not an inherently balanced design like a straight-6, V-12, flat-6, or V-8 (ignoring the counterweights) and does still have a small second order rocking motion, which can only be compensated by two additional balance shafts.

 Road cars

Until recently, the V10 configuration was not a common configuration for road cars; a V12 is only slightly more complicated and runs more smoothly, while a V8 is less complex and more economical. Nevertheless, modern engineering has made it possible to use V10 engines for applications where a V8 would produce insufficient power and a V12 would be too complicated or bulky For the Lexus LFA, the engineers selected a V10 engine over an equivalent displacement V8 because they could not get the V8 to rev as high as the V10, and over a V12 for its lower reciprocating mass, allowing for more rapid engine response. For Audi in their Audi S8 5.2 FSI quattro, the V10 was a compromise between a V12 which would be too long and suffer more internal friction due to extra cylinders and values, and a V8 which would be more compact but have larger heavier pistons and produce lower revs.

Dodge was the first to develop a modern V10 engine, originally designing a version of its LA series small block for use in trucks. The Dodge engine saw its first production use in substantially revised form in the Dodge Viper while the truck version of the engine was used starting with the 2nd generation Dodge Ram . It discontinued in that application after 2003. However, 2003 also saw the introduction of the Dodge Ram SRT-10, a performance model meant to rival Ford's successful V8 powered F-150 SVT Lightning. The Viper engine (a 90-degree engine with odd firing order to obviate the need for a balance shaft) has been tweaked through the years, and for the fifth-generation Viper produces 640 hp (477 kW; 649 PS) in a standard state of tune from its 8.4 liter displacement. The previous generation engine is used by Bristol, in tuned form, in their two-seat Fighter coupe, where it can produce upward of 630 hp (470 kW; 639 PS).

Ford also developed a heavy-duty V10 version of their Triton engine to replace the 460 big block in truck applications. It was introduced in the E-Series/Econoline full-size van. The F-Series Super Duty and Excursion SUV furthered the engines popularity. The Triton 6.8 V10 is still in production today.

European marques were slower to adopt the V10 configuration. However, high-revving V10 power-plants were incorporated into supercars from Lamborghini and Porsche. BMW and Audi later unveiled ten-cylinder versions of their mid-range saloons (the BMW 5-Series and Audi A6 families, respectively). Audi here profited from their Lamborghini ownership, which allowed them to source the Gallardo's V10 for their own cars. Volkswagen also developed a turbodiesel V10; their Volkswagen Phaeton was the first production sedan to have a V10.

A list of post-war V10-engined production cars (sorted alphabetically by manufacturer, sub-sorted by year of introduction):

• Audi S6 (C6) - 5.2 liter
• Audi RS6 (C6) - 5.0 L bi-turbo
• Audi S8 (D3) - 5.2 L
• Audi R8 - 5.2 L
• BMW M5 (E60) - 5.0 L
• BMW M6 (E63/E64) - 5.0 L
• Bristol Fighter (Dodge V10)
• Devon GT X (Dodge V10)
• Dodge Viper (the first modern V-10-engined car)
• Dodge Ram 2500/3500 Heavy Duty (pickup trucks)
• Dodge Ram SRT-10 (pickup truck)
• Ford E-350 (full-size van)
• Ford Super Duty (pickup trucks)
• Ford Excursion (3/4 ton SUV)
• Lexus LFA - 4.8 L
• Lamborghini Gallardo - 5.0 L (5.2 L for LP560-4)
• Lamborghini Sesto Elemento - 5.2 L
• Porsche Carrera GT - 5.7 L
• Volkswagen Touareg - 5.0 TDI PD
• Volkswagen Phaeton - 5.0 TDI PD
• Wiesmann MF GT 5 (BMW S85-B50)

Racing

The most widespread use of the V10 has been in Formula One racing. Alfa Romeo made the first modern Formula One V10 in 1986, although it was never used in a Formula One car. Later the configuration was introduced by Honda and Renault before the 1989 season. The introduction of the 3.5 litre rule after turbos were outlawed following 1988 made the V10 seem the best compromise between the V8 and V12. V10 engines became commonplace after the reduction from 3.5 to 3 liters in 1995, and were used exclusively by teams from 1998 to 2005. Renault had a more flat 110° angle in 2002 and 2003, but reverted to a more conventional 72° following the change in rules which dictated that an engine must last two race weekends. In a further change to the rules, V10s were banned for the 2006 season onwards in favor of 2.4 liter V8s, however a concession was made in that season for teams to use significantly rev limited V10s; Scuderia Toro Rosso being the only team to use this option.

The Audi R15 LMP1 Uses a TDI V10 Diesel Engine which made its debut in 2009 12 Hours of Sebring

There are also cars with V10 engines in sports car racing, usually with Judd power plants with 4 or 5 liter engines, made available for customers, although the first V10 was seen in the works Peugeot 905 and the Works Toyota TS010, in the final races of the 1990 World Sportscar Championship season.

The V5 engine is a V form engine with five cylinders.

Volkswagen

Volkswagen introduced the first V5 engine, though this engine is not a true twin-bank V engine, but rather a VR5, or staggered bank straight-5 engine, and therefore not a true V5. It does not have one cylinder bank with 2 cylinders and one with 3; rather, it has all 5 cylinders sharing a single bank. The engine is derived from the VR6, and is thus a staggered 5, and has much in common with Volkswagen's earlier straight 5 developed in the 1980s for the Passat and Audi Quattro.

Volkswagen's VR5 is a 2.3 litre gasoline engine descending directly from the older VR6 from which VW removed a cylinder creating the first block to use five cylinders in a V design. The first version, with 2.3 L capacity, was capable of 150 PS (148  hp/110  kW) and had a maximum torque of 209 N·m (154 lb·ft).

It was introduced in the Passat in 1997, and later in the Golf, Bora (aka Jetta) and the Spanish Seat Toledo (Typ 1M) in 1999. In 2000 the head was updated with twin cams, and was equipped with 20 variable timed valves thus raising power to 170 bhp (127 kW; 172 PS).