- Bentley Continental GTC V8, 2013
The red winged 'B' and black gloss grille provide a strong indicator that a different Bentley powerplant nestles in the engine bay of the Bentley Continental GT V8 and its convertible stablemate.
Settle into the supportive cobra-style seats, press the start button, and all is revealed. The new 4.0 litre Bentley engine comes to life with an unmistakable V8 burble: deep, sporty and ready for action.
To achieve the 40 per cent efficiency improvement targeted by Bentley's Board of Directors back in 2008, Bentley's engineering team left no detail unexamined. The reduction in displacement from 6.0 litre W12 to 4.0 litre V8 was the first starting point - but a smaller capacity engine in itself would not have delivered anything close to the ambitious power and emissions targets.
Variable displacement - deactivating cylinders when at a gentle cruising speed or light throttle - was already an area of Bentley expertise. The Bentley Mulsanne's 6.75 litre V8, though similar in format to the original Bentley V8 of 1959, features variable displacement as part of its technologically-advanced specification.
Similar technology now features on the Bentley 4.0 V8: when the engine's control microprocessor detects a light throttle opening as the driver maintains a steady cruising speed or gentle acceleration or deceleration it closes the valves in four of the eight cylinders so that they simply act as air springs.
This has two immediate benefits; the remaining four cylinders operate at a higher level of efficiency, and the engine's frictional and gas transfer losses are reduced. As soon as the driver presses the throttle harder the engine instantly switches back to full eight-cylinder operation.
Switchable hydraulic engine mounts compensate for the different resonances of V8 and V4 mode, as the mount switches to a 'soft' state during idle for improved isolation from vibration.
Seamlessly managing the transition between modes and maintaining optimum efficiency throughout the V8's operating range is a highly advanced engine management system (EMS). A 32-bit TriCore™ microprocessor performs up to 180 million instructions per second, providing an unparalleled level of precision in its control of the combustion process.
The EMS also controls the thermal management system that ensures a faster warm up for the engine and transmission, as well as the switchable oil control system, each of which has a contribution to make to the new model's overall 40 per cent efficiency gain.
Another key component of the innovative V8 powertrain is the new close-ratio 8 speed automatic transmission. Not only does it deliver faster, smoother gearshifts, it also accounts for 6 per cent of the total 40 per cent efficiency gain achieved by the new V8. Having a greater number of ratios ensures that the engine is always working at its most efficient gearing, while drag torque losses have been minimised within the transmission.
New thermal management features ensure that the V8 reaches its most efficient working temperature as swiftly as possible, minimising losses via the unwanted extra drag of cold lubricants and bearings.
A rapid warm-up valve keeps coolant inside the engine until a preset temperature has been reached. It then diverts the warm coolant to the transmission, heating it rapidly thereby reducing energy losses. Only when both major drivetrain components have reached their most efficient operating temperatures does the coolant enter the full cooling system.
In the quest for efficiency, Bentley engineers considered the design of every component to minimise energy losses without compromising power or durability. This process of 'engine optimisation' encompassed everything from oil viscosity, variable oil pressure and indirect intercooling to the use of low friction bearings. Unusually, as well as being technically demanding to achieve, the turbochargers are mounted within the 'V' of the V8, contributing to efficiency and weight reduction, a process that Bentley's engineering describe as 'super side inside'.
Bentley's engineers have also designed the electrical system to work in a more efficient way, reducing the amount of power sapped by the alternator. Using the principle of recuperation, the alternator's output is 'topped up' by the battery at low engine speeds, then the process is reversed via energy recovery during those times when the car is decelerating.
Over a typical drive cycle this can reduce fuel consumption by 4 per cent, while the 'on demand' variable power assistance for the steering adds a further 3 per cent efficiency gain. Even the specification of the tyres had an additional 1 per cent efficiency gain to contribute, naturally without compromising the Bentley's limpet-like grip and responsive handling characteristics.
As a result of these incremental gains through the use of advanced engineering technology, the new Bentley Continental GT V8 does indeed offer a 40% improvement, compared to the W12-engined Continental GT of 2008, the date when the commitment was made.
But the greatest achievement of all is that the thunderous Bentley performance characteristics are maintained. Full throttle acceleration will catapult the Bentley Continental GT V8 or GTC V8 past sixty miles an hour in less than five seconds; performance figures only surpassed by the 6.0 litre W12 powered models.
Better still, it will do so with an intensity of aural and sensory feedback - a deep growl rising to a full throttle racer's pitch - that delivers a new form of Bentley driving exhilaration. Bentley's engineers accepted no compromises in their pursuit of efficiency - and as a result, the owners of the new Bentley Continental V8 models need make no compromises in their enjoyment of its performance.
Contemporary, sporting design character
The new Bentley Continental V8 models have all the sculpted, muscular elegance of their W12 stablemates, with their distinctive wide rear track, super formed aluminium wings, powerful haunches and low, poised stance. But a number of key differences distinguish these branches of the Continental family.
One of the most significant differences is also one of the smallest. When it appears on the Mulsanne and the 6.0 W12 Continental models the winged 'B' emblem above the radiator grille has a black enamel background.
On the Continental V8, the enamel is red. It's a distinction that dates right back to the 1920s, where the 'red label' badge appeared upon the company's smaller cars, such as the short-chassis 3 Litre, while black badges were usually reserved for larger-engined models.
Other external distinguishing features are more striking. The radiator grille of the V8 models features gloss black mesh, bordered by a fine chrome surround, in place of the W12 Continental GT's brightwork.
Underneath the grille the lower bumper also features black mesh and is divided by strakes into three distinct segments. The effect, both literally and figuratively, is a Bentley with a darker side to its character; potent, muscular and challenging.
At the rear two eye-catching 'figure eight' exhaust pipes, one each side of a dark lower rear valance, tell those in the know that this Bentley is powered by the advanced, exhilarating and efficient new 4.0 litre V8.
Both the coupe and convertible will be launched with 20-inch wheels as standard and customers will also be able to select from two 21-inch wheel designs especially created for the Continental V8 models. Both these options feature a six-spoke alloy with a strong, sporting theme and are finished in either Diamond Black (exclusive to the Continental V8) or Diamond Silver. Each Bentley 'B' emblem featured on the wheel centre caps is also finished in red.
The cockpit of the two Continental V8 models has a correspondingly sporty ambience, featuring a new veneer, Dark Fiddleback Eucalyptus, for the fascia and trim. Both the coupe and convertible feature a technical finish Eliade cloth headlining, rather than the leather that is standard in their W12-engined counterparts.
Unlike the full through-console of the W12, the centre console simply separates driver and front passenger seats, underscoring the sporting, lean and weight-conscious ethos of the V8 models.
Both the coupe and convertible will be offered with a choice of four single-tone interior hide colours, seven exterior finishes and (in the case of the GTC) three hood colours.
However, owners wishing to access the full palette of 17 exterior finishes, 17 hide colours, up to seven interior duotone colour 'splits' and eight hood colours available on the Continental W12, can take this option. This also brings access to the full Bentley range of veneers and a new sporty duotone seat design.
Other optional packages include the Driving Specification, Mulliner Styling Specification, Touring Specification and Convenience Specification. Many, however, will prefer the sporting, focused simplicity of the single-colour interior with its contemporary, clean Fiddleback Eucalyptus trim and Eliade cloth headlining.
0 comments:
Post a Comment