The V12 engine was born in a London workshop to power racing boats
The first V12 was not built for a car at all. In 1904 Putney Motor Works in London made one for racing boats, a hefty 18.4 litre design whose camshaft could slide to run the engine backwards for going astern. Its smoothness soon won it places in luxury cars, fighter planes, tanks and ocean liners.
The appeal is balance. Each bank of six cylinders behaves like a straight-six, which is perfectly balanced on its own, so two together run with remarkable calm. At any moment three cylinders are firing, meaning there is never a gap between power pulses. Most designs set the banks 60 degrees apart, which gives evenly spaced firing. The price is cost, complexity, extra friction and an engine that is long and heavy.
Its shape decides where it fits. A 60-degree V12 is narrower than a comparable 90-degree V6 or V8 but longer, awkward in a passenger car yet ideal where width is tight and length is free. That is why it suits locomotives squeezed by railway clearances, tanks limited by street widths and twin-propeller boats that need engines side by side. In piston-engined fighters and bombers, the long slim profile was far more streamlined than a stubby radial.
Aviation drove much early development. Renault produced the first aircraft V12 in 1912, a 90 horsepower unit that turned the propeller off the camshaft at half speed for better efficiency. Britain's Sunbeam Mohawk became the country's most powerful aero engine when the First World War began, and the American Liberty L-12 followed. Aircraft V12s peaked in the Second World War before jets took over.
In Formula One, V12s were common in the late 1960s and again in the early 1990s but have since faded from racing. Today they survive mainly in some European sports and luxury cars, locomotives, generators and ships. Big cruise liners may carry six of them, and a single marine V12 from Wärtsilä displaces 1,157 litres and produces 14,400 kilowatts.
Source: V12 engine
