Manufacturing of the marque’s 12-cylinder engine has come to an finish – we clarify how Crewe made it so easy
One chapter within the story of our love affair with 12-cylinder engines has come to an finish with information that Bentley has lastly ceased W12 manufacturing.
Regardless of this engine being hand-built from 2600 components, every instance was completed pretty rapidly – in seven hours.
As soon as put in and fired up, the 6.0-litre, twin-turbocharged big was able to powering a Continental GT to a staggering 208mph.
It had been redeveloped over a three-year interval for the introduction of the Bentayga in 2015, with faster-responding twin scroll turbos and cylinder deactivation on one financial institution of six to cut back consumption when the driving force lifts or trails the throttle. For its first use in an SUV, it was additionally examined to carry out at tilt angles of as much as 35deg.
Affection for 12-cylinder engines has endured with good cause. Many automotive makers have chosen V12s for refinement and energy, and Crewe selected the identical route however with a W12, which is a detailed relative with one delicate however necessary tweak.
Earlier than we get to that, what are the qualities which have made V12s so fascinating and enduring for nearly all the historical past of the combustion engine, and why have them?
An engine’s smoothness is set by how little it vibrates. Two of a very powerful issues deciding which are main stability (vibrations that happen at each revolution of the engine) and secondary stability (each two revolutions).
Issues that trigger these vibrations are reciprocating lots (the burden of inner components transferring vertically or horizontally) and rotating lots, such because the crankshaft and combustion forces every time a cylinder fires. There are many different components that additionally have an effect on stability, together with the cylinder firing order and whether or not particular person reciprocating components like pistons and conrods all weigh exactly the identical.
Straight-six engines have excellent stability, largely as a result of the variety of cylinders permits motion of the pistons to be completely orchestrated. So it follows {that a} V12 with two banks of six cylinders needs to be in excellent stability as nicely, and it’s. The W12 follows swimsuit however is so – referred to as as a result of, like Volkswagen’s outdated VR6, the cylinders in every financial institution are offset by 15deg in order that they are often nearer collectively, making the engine 24% shorter.
However it nonetheless solely has two banks of cylinders, like a standard V12, though the identify suggests it may need 4 to kind a extra literal W form. Like a V12, the W12 can also be easy as silk, passing the ‘coin check ’, the place a coin can stand unaided on its floor at idle.
It owes a minimum of a part of that refinement to the hand-building in addition to good genes, with pistons and conrods being sorted into balanced units weighing inside fractions of a gram.
