Our progressive journey towards sustainable luxury mobility means making changes to every area of Bentley Motors .
engine is run over an extended test cycle and then fully stripped for inspection .
The W12 engine facility will have delivered over 105,000 engines before reaching its 20th anniversary this year .
BATUR SHOWCASES THE ULTIMATE W12
For the final and ultimate version of the W12 , Mulliner ’ s engineering team has reworked the intake , exhaust and cooling systems to liberate more power and torque than ever before . Under the watchful eye of Mulliner ’ s Chief Technical Officer , Paul Williams ( who previously led the development of the second-generation W12 ), the engine is now signed-off at 750 PS and 1,000 Nm of torque – both record-breaking figures for the engine .
The turbocharger compressors are of a new design to improve efficiency , while the ducts that feed air to them are 33 per cent larger – at peak power , the new engine ingests more than a ton of air ( 1,050 kg ) per hour . Larger charge-air coolers , with a depth increased by 10 mm and a new core geometry , reject 35 per cent more heat from the pressurised intake air , reducing intake temperature to a greater extent meaning a denser charge for more power .
The new intake and turbocharging system is matched with a heavily revised engine calibration to liberate the extra torque available , and the complete engine system is then paired with a new transmission calibration to deploy the additional power and torque and enhance the driving experience .
THE EVOLUTION OF AN ICON
Bentley ’ s legendary 6.0-litre twinturbocharged W12 , created in 2002 , has evolved into the latest iteration of W12 engine used across today ’ s current model range . The unique W-configuration means that the engine is 24 per cent shorter than an equivalent V12 , benefitting packaging and maximising usable cabin space .
The latest generation of W12 was launched in the Bentayga in 2015 . A thoroughly reworked engine included a crankcase 30 per cent stronger than its predecessor , while the cylinder surfaces were coated to reduce friction and improve corrosion resistance . A low-alloy steel coating is applied to the bores using an Atmospheric Plasma Spray ( APS ) process .
Improvements were also made to the cooling system , with the engine featuring three separate coolant circuits . The first is designed to bring the cylinder heads up to optimum operating temperature as quickly as possible for best engine performance and low emissions . The second cools the engine block and oil system , while the third handles the thermal load of the turbochargers . Each system has a dedicated water pump , allowing optimised individual control .
The W12 combines high-pressure direct fuel injection ( 200 bar injection pressure ) with low-pressure port injection ( six bar ). The combination of these two systems maximises refinement , lowers particulate emissions and optimises power and torque delivery .
Twin-scroll turbochargers minimise turbo response time and provide a more efficient exhaust package . The exhaust assemblies for the three front and three rear cylinders are separate from one another which then feed the twin-scroll impellers . The turbocharger housing is welded directly to the exhaust manifolds and feature integrated speed sensors , allowing the engine to monitor turbo performance for maximum efficiency .
Bentley ’ s Variable Displacement system shuts down half of the engine under defined conditions . Intake and exhaust valves , fuel injection and ignition are all shut down on defined cylinders , with the engine running as a six-cylinder for improved efficiency . The system will run in this mode in gears three to eight , below 3,000 rpm and up to 300 Nm torque output .
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