The Short and Intriguing History of V-16 and W-16 Engines
Only a handful of cars were powered by 16-cylinder engines, and this is the definitive listby Ciprian Florea, on
The production automobile started life with relatively small engines, but as luxury cars emerged in the 1920s, carmakers began developing larger V-8 and V-12 engines. Some companies even went as far as to develop massive V-16s.
Although these engines delivered lower vibration, thus increasing comfort inside the cabin, they typically produced as much power as a V-8 or V-12 engine, while being notably more expensive to produce. As a result they were rarely used in automobiles. Let’s have a closer look at the short but intriguing history of V-16 (and W-16 for that matter) cars below.
The V-16 debuted in production road cars in the United States in the early 1930s as a result of a technology war between Marmon and Cadillac. They were also used in some race cars in Europe before World War II, but their use beyond the 1950s was mostly limited to concept vehicles. While some are quite famous, others have remained almost unknown.
1930 Cadillac Series 452
Cadillac wasn't the first automaker to develop a V-16 engine, but it was the first to put it into a production car.
Cadillac’s design is pretty controversial, as it was developed by an engineer recruited from Marmon, the first automaker to develop a V-16 engine in the United States. Hired in the early 1920, Owen Nacked designed a V-16 for Marmon by 1926, but in 1972 he switched to Cadillac, where he started working on a similar mill. Developed in complete secrecy, the V-16 debuted in 1930 in the Cadillac Series 452.
The company’s new range-topping model, the Series 452 featured a narrow 45-degree V-16 with an overhead valve, a layout inspired by the Marmon engine. The massive 7.4-liter mill tipped the scales at a whopping 1,300 pounds and delivered 175 horsepower.
The car attracted rave reviews from the media and the public in the United States, so Cadillac sent five cars in a promotional tour in Europe that included 24 cities in 10 countries. The Cadillac V-16 was a massive success in 1930, with no fewer than 2,000 cars sold by June. But as depression hit the United States, demand dropped dramatically over the next months and Cadillac eventually sold less than 4,000 by 1937, when Cadillac introduced a new V-16 engine.
1931 Marmon Sixteen
Founded as a manufacturer of flour grinding mill equipment in 1851, Marmon started building cars in the early 1900s. By the 1910s, Marmon was already famous in the United States.
Marmon is also known as the first company to design a V-16 engine for automotive use.
Word has it Marmon Howard got the idea while in France, during World War I. Deployed there to lead the American Air Corp Technical Team, Marmon studied Bugatti’s U-16 jet fighter engine and presented his idea of a V-16 design to engineer Owen Nacker in the early 1920. A single crankshaft, overhead valve V-16 with reverse flow outboard intake and exhaust manifolds was finished by late 1926, before Nacker was recruited by Cadillac.
Following Nacker’s departure, Marmon altered the engine’s design to include fork-and-blade connecting rods, a central camshaft, dual downdraft carburetor, and aluminum crankcase, cylinder blocks, and cylinder heads.
The engine debuted in the Marmon Sixteen in 1931, a year after Cadillac introduced its own mill. Although he narrowly missed being the first to launch a production V-16, Marmon takes credit for having design a more modern mill that weighed less than 1,000 pounds and generated 200 horsepower. The V-16 was also the largest produced with a displacement of eight liters. The Marmon Sixteen was produced for three years in small numbers. Marmon offered a variety of body styles, including sedans, coupes, and convertibles.
1938 Cadillac Series 90
While Marmon went bankrupt during the Great Depression and the Sixteen disappeared after only three years, Cadillac’s V-16 car lived long enough to feature a second-generation engine. Although it sold only 50 units a year from 1935, Cadillac decided that its range-topping model, now renamed the Series 90, needed a new engine for 1938.
And unlike the first V-16, the new mill marked a return to Cadillac’s more traditional flathead design and featured a wider, 135-degree angle. It also included twin carburetors and twin fuel pumps.
Smaller than its predecessor at 7.1 liters, the flathead V-16 was just as powerful as the later versions of the overhead valve variant at 185 horsepower.
However, the new V-16 was nearly silent at idle, operation was smoother, and turned the Caddy into one of the quickest accelerating cars of its time. The engine also returned slightly better fuel economy.
But the revised V-16 model wasn’t as popular as the original car. Cadillac sold 315 units in 1938, 138 examples in 1939, and another 55 before the nameplate was discontinued in 1940.
The Cadillac V-16 was the first and also the last production car with a V-16 engine to emerge in the United States. Cadillac eventually built a concept car with a V-16 in the 2000s, but it never went into production.
1932 Peerless V-16
Marmon and Cadillac weren’t the only American companies that produced V-16 engine before World War II. Peerless also developed one, but just like Cadillac, it was based on Marmon’s design. That’s because Peerless was joined in 1929 by James A. Bohanon, who had been Marmon’s purchasing agent for six years.
Bohanon brought his knowledge of Marmon’s V-16 engine to Peerless, which designed a similar engine with a single crankshaft and an aluminum crankcase, but went with alloy blocks and heads and did not use Marmon’s crossflow design. The engine was lighter than Cadillac’s, but heavier than the V-16 that Marmon eventually launched in 1931.
But unlike its competitors, Peerless didn’t get to put its engine into production. Peerless completed a V-16 prototype in 1931 and showcased it for the 1932 model year, but the company stopped producing cars as sales of luxury vehicle dropped due to the Great Depression. Two V-16 coupes were in the work at Murphy’s Pasadena body shop when Peerless decided to stop production. When the Prohibition ended in 1933, Peerless converted its car factory into a brewery.
About 63 years after it discontinued its first V-16 car, Cadillac revisited the idea for the Sixteen concept.
A full-size sedan that paid tribute to Cadillacs from the 1930s with its center-hinged, dual-design engine hood, the Sixteen was powered by a massive, 13.6-liter V-16 developed specifically for this concept car.
Although GM had the option to weld a couple of V-8 crate engines together, it eventually decided to built a V-16 from scratch. However, the company’s engineers did use the 6.0-liter V-8 of then upcoming C6 Corvette as a starting point, including its variable cam timing, a first for a pushrod design, and Displacement on Demand. The latter was an older active fuel management system that shut down cylinders to save fuel under low-load conditions. It could shut down either 12 or eight cylinders, which led to a combined fuel economy of 16.6 mpg.
Cadillac claimed that the 13.6-liter V-16 engine was capable of in excess of 1,000 horsepower and 1,000 pound-feet of torque. These are impressive figures for a naturally-aspirated engine.
Bugatti, for instance, needed four turbochargers to blow past the 1,000-horsepower mark with the W-16-powered Veyron in 2005. Despite initial rumors that the Sixteen might go in production, it remained just a concept. However, the exterior design of the Sixteen inspired upcoming generations of the CTS sedan and even the Escalade SUV.
Read our full review on the 2003 Cadillac Sixteen
2004 Rolls-Royce 100EX
One year after Cadillac shocked the world with its massive V-16, Rolls-Royce introduced the 100EX concept. A two-door version of the Phantom built to celebrate the 100th anniversary of the meeting of Charles Rolls and Henry Royce, the 100EX was powered by a 9.0-liter V-16 engine developed by BMW.
The engine was rated at an impressive 770 horsepower and 1,100 pound-feet of torque, but it never went into production.
The 100EX was followed by a coupe version called the 101EX in 2004, which previewed the Phantom Drophead Coupe. The production model was launched with a V-12 engine instead.
1988 BMW 767iL Goldfisch
The V-16 in the Rolls-Royce 100EX concept wasn’t the first such engine developed by BMW. The German firm began working on its first V-16 as an experimental engine in 1987. Known as project Goldfisch, the V-16 was actually an M70 V-12 engine with four extra cylinders.
The 6.7-liter mill featured a cast aluminum block and cylinder heads, two valves per cylinder, and generated a maximum output of 402 horsepower.
Tested in 1988, the engine was mounted in an E32-generation 7 Series model. BMW went with a 750iL version, usually powered by a V-12, and called it the 767iL. Because the engine was longer than the V-12, BMW was forced to install a cooling system in the trunk and massive cooling vents in the rear fenders. So not only the 767iL looked weird, but it had also lost its practicality without space in the trunk.
The engine was presented internally within BMW, but the company decided to pass on the idea. On top of not being very practical due to its size, BMW bosses also considered that a production V-16 would start an "arms race" with other manufacturers, Mercedes-Benz included. What’s more, BMW was already working on a beefed-up version of its M70 V-12 engine with 375 horsepower, only 27 horses below the V-16.
The engine was also trialed in the first-generation Bentley Mulsanne as a possible upgrade to the already available V-8. Because it featured a massive, 6.75-liter V-8, the Mulsanne had plenty of room for the V-16 and its cooling system in its engine bay, but the project was shelved and Bentley continued to use naturally aspirated and turbocharged V-8 engines.
1989 Mercedes-Benz 800 SEL
Having learned of BMW’s Goldfisch project, Mercedes-Benz began developing its own V-16 engine. Details on Stuttgart’s plans remain vague to this day, but the automotive media reported about an S-Class model with a V-16 engine in early 1989. That’s when Mercedes-Benz was still working on the W14-generation S-Class, which was launched for 1991.
Rumor had it that the V-16 would power a range-topping model called the 800 SEL, which would slot above the 600 SEL. The latter broke cover with a V-12 engine rated at 400 horsepower and 428 pound-feet of torque.
There were also reports that Mercedes-Benz had built a small fleet of 85 prototypes with the V-16 engine, but there’s no proof of their existence aside from some drawings of the engine. The V-16 was reportedly cancelled due to the increasing concern for climate protection and fear of sending a wrong message to the public.
Apparently Mercedes-Benz also considered a W-18 engine for the S-Class. This mill never made it past the blueprint stage, but it seems that the engineers in Stuttgart used three 2.6-liter six-cylinder engines to create the W setup. Documents from the company’s archives show a version with two valves per cylinder and 490 horsepower and a variant with five valves per cylinder and 680 horsepower. Needless to say, it would have created a monster of an S-Class, but it would also have been a packaging nightmare.
|Engine:||V-16 with unknown displacement|
|Production years:||1989 (rumored)|
|Units produced:||85 prototypes (rumored)|
The Devel Sixteen is by far the most ambitious V-16 car envisioned so far. Unveiled in 2017, the prototype was built in the United Arab Emirates and it looks like it came from space.
Heavily inspired by jet fighter designs, it features a very short and slanted nose, a canopy-style cabin, and a very long and aerodynamic rear section. Under the hood, the Sixteen hides a quad-turbo V-16 built by Steve Morris Engines from Michigan. Upon unveiling the prototype, Devel claimed a power rating of around 5,000 horsepower, a sprint to 60 mph in just 1.8 seconds, and a top speed of around 350 mph.
Although the prototype is fully functional, a production model has yet to surface, but Steve Morris Engine released footage of the engine generating a whopping 5,007 horsepower on the dyno.
Read our full review on the 2017 Devel Sixteen
1929 Maserati Tipo V4
One year before Cadillac launched the first production car with a V-16 engine, Maserati fitted some of its race cars with experimental V-16s built from two Alfa Romeo 26B mills into a single crankcase and transfer case.
However, they each had individual supercharges and prototype Weber carburetors mounted by Edoardo Weber himself. The engine displaced only 4.0-liters and generated a solid 305 horsepower.
The Tipo V4 made its first outing at the Gran Premio di Monza in 1929, but struggled due to increased tire wear and reduced braking at the front (all due to the heavy twin-engine setup). An upgrade model managed to win the Gran Premio di Tripoli and take third places at Monza and Coppa Acerbo. But the Tipo V4’s biggest achievement was setting up a world speed record of 152.8 mph at a special event in Cremona, Italy.
1930s Auto Union race cars
Formed in 1932 by struggling auto manufacturers Audi, DKW, Horch, and Wanderer, Auto Union wanted a show piece project for the German car shows. Auto Union chairman was advised to meet with Ferdinand Porsche, who had just established a race car division. In 1933, Adolf Hitler announced a state-sponsored racing program for Mercedes-Benz, but he was eventually persuaded to include Auto Union as well With sponsorship from the German government, Porsche went on to develop a mid-engined, RWD car, a layout that was unusual at the time.
The original car was called the Auto Union Type A, but it was followed by upgraded models named the Type B, C, and D, all of which raced through 1939.
The Type A, B, and C cars were all powered by V-16 engines with displacement ranging from 4.4 to 6.0 liters.
The first cars developed around 295 horsepower, but later models surpassed the 500-horsepower barrier. Far more spectacular in appearance than cars from rivals Mercedes-Benz, the Auto Union were also competitive, winning numerous racing in the European Championship, the series that preceded Formula One. Auto Union also set several records, including a top speed of 199 mph with a streamlined car with enclosed cockpit. The Type C was rumored to be able to hit 211 mph.
Unlike its predecessors, the Type D was powered by a supercharged V-12 engine. Production of Auto Union race cars stopped when World War II broke out and many of the cars were lost during the conflagration.
|Engine:||4.4- to 6.0-liter V-16|
|Power:||290 to 513 horsepower|
|Torque:||391 to 629 pound-feet|
1938 Alfa Romeo Tipo 316
As Auto Union was moving away from the V-16 engine for the 1938 racing season, Alfa Romeo was preparing to enter a car fitted with a 16-cylinder mill in European Championship. Called the Tipo 316, it was part of a three-car lineup designed specifically for the new rules of the 1938 season. The other two were the Tipo 308 and Tipo 312, fitted with straight-eight and V-12 engines, respectively. The 316 was based on the 12C, a car that Alfa Romeo produced in 1936 and 1937.
Alfa's V-16 engine, designed by Gioacchino Colombo, who later created some of Ferrari's most iconic powerplants, displaced only 3.0 liters, but it featured a supercharged and generated 350 horsepower.
It had a 7,500 redline and powered the Tipo 316 to a second place finish in the Grand Prix of Italy. In 1939, Alfa Romeo lost interest in the project as it started working on the iconic 158 Alfetta race car.
|Engine:||supercharged, 3.0-liter V-16|
1951 BRM P15
Automakers moved away from the V-16 engine after World War II, but British Racing Motors made one final attempt in the early 1950s. Seeking the same success as Auto Union before WW2, BRM set out to create a V-16 engine that would comply with the new Formula One regulations. This meant that it had to displace no more than 1.5 liters. It also had to be supercharged. The engine was rather revolutionary, mostly because it featured a twin centrifugal supercharged instead of the more traditional Roots-type unit. Developed by Rolls-Royce, the supercharger design was based on the units used in the Merlin aero engine. The design allowed for tremendous power at high revs, but it also means that the engine produced significantly less oomph in the lower range. Drivers were thus forced to keep the revs within a very narrow power band and this proved to be the car’s main shortcoming.
The BRM P15 debuted in 1950 in non-championship races and won the Goodwood trophy. BRM enter the car in the Formula One championship in 1951, but the P15 raced in just one of eight events, finishing fifth and seventh. BRM prepared to race the car in F1 in 1952 as well, but with Alfa Romeo retired from the series and Ferrari left as dominant force, the FIA decided to run the season with Formula Two regulations.
The P15 didn’t meet these new regulations so the project was abandoned. The P15 was raced in five more non-championship events through 1953, scoring second place at the Albi Gran Prix and winning the Glover Trophy at Goodwood in 1953. The BRM P15 was the last race car to feature a V-16 engine.
|Engine:||supercharged, 1.5-liter V-16|
The W configuration is notably different than the more familiar V layout, because they feature three or four cylinder banks on the same crankshaft. When viewed from the front, the layout resembles the letter W. However, these engines also feature 16 cylinders, so they have a well-deserved place on this list. W-16 engine are notably scarcer than V-16 mills. While the latter made its first appearance in a car in 1930, the W-16 did not debut in an automobile until 1995.
1995 Jimenez Novia
The Novia was the first ever car fitted with a W-16 engine and only one was built.
A one-off supercar, it was developed by Ramon Jimenez, a French motorcycle racer, as a tribute to the iconic Porsche 917. Development reportedly started in 1985 in a small workshop in Avignon, where Jimenez made his own carbon-fiber composite panels from scratch. A single car was finished in 1995, powered by a 4.1-liter W-16 made by combining four Yamaha FZR1000 motorcycle engines. The W-16 was rated at 560 horsepower and enabled the Novia to hit a verified top speed of 236 mph, a record at the time.
The Novia cost Jimenez almost $900,000 and his initial plan was to enter the car in the 24 Hours of Le Mans race and put the car into series production with a price of around $300,000. Both projects failed due to financial difficulties and the fact that the French government mandated that a separate chassis be made for crash testing.
Following a decade of experimenting with W-18 engines, Bugatti eventually settled for a W-16 for the Veyron.
Introduced in 2005, the Veyron was the first series production car with such an engine. The powerplant was created by joining two Volkswagen VR8 engines at the crankcase and placing them on a single crankshaft. Considered a technological wonder, the quad-turbo W-16 in the Veyron debuted with 987 horsepower and 882 pound-feet of torque, but it was later on upgraded to deliver 1,184 horsepower.
The engine helped Bugatti set a world top speed record of 253.8 mph with Veyron in 2005 and 267.8 mph with the Veyron Super Sport in 2010. The same engine was used in the Bentley Hunaudieres, Audi Rosemeyer, and Bugatti 16C Galibier concept cars. The Bentley and the Audi featured earlier, naturally aspirated versions of the mill. The Veyron remained in production for 10 years, spawning a handful of variants and countless special edition models.
|Engine:||quad-turbo, 8.0-liter W-16|
|Power:||up to 1,184 horsepower|
|Torque:||up to 1,106 pound-feet|
Read our full review on the 2005 Bugatti Veyron
The Chiron replaced the Veyron in 2016 and continued the legacy of the 8.0-liter W-16. A heavily redesigned car inside and out, the Chiron also features an updated version of the quad-turbo W-16.
The mill generates 1,479 horsepower in the standard Chiron and 1,578 horses in the limited-edition Super Sport 300+.
The latter was built to celebrate a new top speed record achieved with a prototype model at 304.7 mph, making the Chiron the first production car that broke the 300-mph barrier. Just like the Veyron, the Chiron spawned various limited-edition models, but it was also used as a base for heavily modified versions, namely the one-off La Voiture Noire and the limited-edition Divo and Centodieci. Bugatti plans to built 500 Chirons before developing a replacement. However, the W-16 could be discontinued once the Chiron goes into the history books.
|Engine:||quad-turbo, 8.0-liter W-16|
|Power:||up to 1,578 horsepower|
|Torque:||up to 1,180 pound-feet|
Read our full review on the 2016 Bugatti Chiron