Bentley is currently celebrating 100 years of being a motor vehicle manufacturer, and for 60 of them it has been building its venerable V8 powerplant, still the centerpiece of its flagship models to this day.
It may be the longest-serving V8 in production but it still retains the unstressed performance characteristics and superb refinement that gave it its enviable reputation all those years ago. It was originally fitted to the S2 model of 1959, and underwent regular updates and improvements over the years, increasing capacity to 6.75-liter in 1971 and implementing a number of major changes in 1980 for the Bentley Mulsanne to meet stricter emissions and safety regulations (including a collapsible water pump to help with frontal impact performance).
The design brief for the V8 was for it to be at least 50 per cent more powerful than the six-cylinder it was due to replace, while occupying the same space in the engine bay without any increase in weight. Senior engine designer Jack Phillips was asked to undertake the confidential study—and 18 months later Phillips and his team had a running engine.
Dr Werner Tietz, member of the board of engineering at Bentley Motors, said, ‘The original V8 was designed to deliver a step-change in performance, along with smoothness, reliability and refinement. The engine was tested over hundreds of thousands of miles in the toughest conditions, as well as at full throttle for 500 hours. The success of Bentley’s acclaimed 6¾-litre V8 today in the Mulsanne owes much to that ethos.”
The need for additional power saw the introduction of a turbocharger in the 1982 Bentley Mulsanne Turbo, which raised the power output by 50 percent over the naturally aspirated version. Fuel-injection was added a few years later to the Turbo R and continuous development has seen variable valve timing, twin-turbos and cylinder deactivation being integrated into the design too. The culmination of these efforts can be seen in the contemporary Bentley Mulsanne Speed, which develops an impressive 530hp and an astonishing 811lb-ft of torque. That massive torque figure is what gives this engine its unique character. Rapid progress is always a mere prod of the throttle pedal away.
Almost 36,000 of these V8s have been manufactured since 1959, each key internal component still being individually chosen to ensure that the engine runs as smoothly as possible. And while Bentley also uses the VW Group’s capable 4.0-liter twin-turbo V8 in some of its models, the big and torquey 6.75-liter V8 is still reserved for its range-toppers. Bentley owners wouldn’t have it any other way.
Images courtesy of Bentley Motors