Welcome to the launch of the Bentley Continental GT, the world’s fastest four seat coupe, the first all-new and unique Bentley design for over 70 years and its most significant new model since the very first Bentley, the 3-litre, was first seen back in 1919. For Bentley Motors, the Continental GT is more than a product launch as it is symbolic of the change that the company is going through. It is the first offspring of a new family of cars, which deliver unparallelled levels of refinement, craftsmanship and driver involvement - or as Bentley describes this combination, the ultimate British Sporting Grand Tourer.
At the heart of this combination is the company’s belief that the car should be excellent in all rational parameters, but more importantly, should adapt itself to the character that the driver chooses. As a British Sporting Grand Tourer, it should have supercar pace, elegance, and exquisite levels of interior accommodation. As a Bentley, it must have all of these strengths and the capability to cover continents with power and comfort in reserve.
Just four years ago, the team at Crewe, set out to create something appealing and unique in the marketplace, and crucially, in line with the traditions of Bentley. The aim was not to create a pastiche of the past, but to understand the essence of ‘Bentleyness’, and then to carry this forward in a new and exciting way. Inspiration was drawn from the milestones of Bentley history, dating back to the 3-litre of 1919, through the R-Type Continental of the fifties and the now legendary Continental R; and the result is clear.
Rather than the customer having to compromise on comfort, luxury or performance, the Continental GT delivers 198mph (318km/h) top speed, prodigious tractability in all conditions, and levels of accommodation and craftsmanship that are typically Bentley - peerless.
The result is the Continental GT, a car that is as competent as a supercar, as versatile as our customers demand, and as expertly hand-crafted as any car from the home of automotive craftsmanship - Crewe, England.
Key points:
* An all new car, designed, engineered and built by Bentley in Crewe
* The fastest four seat coupe in the world. Top speed 198mph, 0-60mph in 4.7sec (0-100 km/h 4.8sec)
* A Grand Tourer in the finest traditions, capable of conveying four people and luggage in comfort
* Unique twin-turbo 6-litre W12 engine producing 552bhp (560PS) and 479lb ft of torque (650Nm) at just 1600rpm, placing it clearly ahead of Ferrari 456GT, Aston Martin Vanquish and Porsche 911 Turbo.
* All-wheel drive with traction and stability control combined with paddle-operated six speed automatic transmission to provide supremely safe and dynamic response.
* State of the art engineering and production techniques working in seamless harmony with unrivalled handcraftsmanship skills
* Car designed entirely in the virtual world, using some of the most advanced technologies ever used in the field
* Car designed not only be thrilling to drive but also supremely easy to live with, equally effectively as a recreational toy or serious business tool.
* Styling cues include pillarless cabin, minimal front overhang, pronounced haunches, distinctive ‘face’ featuring large inner headlamps, flush mounted rear spoiler that rises at speed.
The dream of building a new Bentley coupé is not new - indeed a secret turbocharged Bentley coupé was built as a feasibility study over 25 years ago - but it is only since £500 million investment programme that the dream could be turned into reality.
This investment has also enabled Bentley to transform the Crewe factory into a thoroughly modern centre of manufacturing excellence, ensuring not only that Bentley is in better shape today than ever, but also guaranteeing its design, engineering and manufacturing sovereignty as far into the future as it is possible to see.
Some 84 years ago, WO Bentley defined what how he wanted a car bearing his name to be viewed in one simple sentence: ‘a good car, a fast car, the best in its class.’ With the new Continental GT, we believe that is exactly what we have created.
Styling
The styling story of the Continental GT dates back to August 1999 when design director, Dirk van Braeckel was briefed to prepare a concept for an all new Bentley coupé: one that would use 80 years of Bentley design as its inspiration, yet look only to the future in its shape. It took just four months - until just before Christmas - when van Braeckel submitted his preferred design to the board of Bentley Motors. It was approved on the spot.
The key to honouring Bentley’s design past without creating a ‘retro’ car, was to take the design philosophy that inspired cars such as the Bentley Speed Six of 1928 and the 1952 R-type Continental and use it in a contemporary context.
Bentley’s design philosophy for the Continental GT can be quantified as follows: the car must have a short front overhang and a dominant bonnet expressed by the unusually large distance between the front axle line and the A-pillar. The pillarless cabin needs to be sleek and compact while the rear haunches should be taut and pronounced, giving the impression of a crouching animal ready to pounce.
Overlaying these highlights is a design language from the hearts of the styling team. It dictated that the Continental GT be styled to be curvaceous and sinuous with a form that appears and disappears like muscle on a gymnast’s arm, sculptural yet lean.
Finally there was what van Braeckel refers to as the car’s ‘jewellery’. It was decided that brightwork should be minimised, limited to the door surrounds, a finish along the sill, the exhaust surrounds and radiator grille. But the headlamps assume a dominant role in the styling with the inner units being the larger of the two pairs in tacit acknowledgment of past Bentleys, and to draw attention to the most distinctive Bentley feature of all: the matrix radiator grille.
Interior design and style
The cabin of the Continental GT is designed to make Bentley devotees and marque newcomers feel equally at home. Those familiar with the Bentley way of doing things will be reassured by the expanses of top quality hide and fine wood veneers; those for whom Bentley ownership is a new experience will discover a new level of luxury, style and effortless good taste.
Bentley is one of few car manufacturers to retain seat design as an in-house field of excellence and the particular challenge with the Continental GT was to offer a sublime seat comfort with considerable front and rear travel, a multitude of electric adjustments and integral seat-belts.
Those used to sitting in the back of most high-performance coupés will scarcely believe the thought that has gone into creating the rear cabin. Far from appearing as afterthoughts, the rear seats have been designed with the same care and attention as those in the front. Back seat passengers sit well apart with deeply scalloped recesses for their elbows, allowing ample personal space.
The toughest task facing designers of all luxury car cabins these days is to present the controls and information interfaces in a way that is both uncluttered yet easy to use.
Bentley’s solution is to use intelligence, common sense and ergonomic know-how to cherry-pick the best elements from both extremes, and combine them in a cabin that is both effective and attractive.
Most routine operations used frequently when the car is in motion - such as the cruise and basic music controls - can be operated directly from the steering wheel. Other functions such as the air-conditioning, navigation, computer information and more advanced entertainment features are individually controlled, but displayed on the same screen sited in the middle of the centre console.
All around the cabin, unmistakeable Bentley touches abound. Perhaps most easily spotted are the classic “bulls-eye” ventilation outlets with their organ stop controls. Then there are the stainless steel pedals, chrome instrument surrounds, knurled finishes to many of the ancillary controls, and the centrally mounted analogue Breitling clock.
The Continental GT is the first car to be fitted with a Breitling timepiece. Designed by Bentley after extensive consultation with Breitling to determine the correct proportioning, size and style of the font and needles, it features a classic black dial with white lettering while its hands are blood orange in colour.
Naturally wood and leather remain as integral and essential a part of this Bentley as any other. And while craftsmanship remains as important as ever, these enduring skills have been supplemented by some 21st century technology allowing, for instance, wood to be dramatically curved in a way that would simply not have been possible in the past. And while the leather is still applied to the car with the same loving care as before, it is cut from the hide using a new digitised process that ensures minimal levels of wastage and maximum efficiency.
Design
The design brief for the Continental GT was to create a car with as much room as the most spacious coupés, equip it with the performance of the world’s most dynamic supercars and retain the whole within compact dimensions.
There are many questions raised by such a demanding specification and it took sizeable measures of blue sky thinking and detailed innovation before it could be realised.
One key to maximising interior space is raising the so-called ‘H’ point - the position in which the driver and front passenger hips naturally sit, and which in all Bentleys is elevated above where it would be in a conventional supercar. The benefits are many: first it means the commanding driving position - another Bentley hallmark - is retained and the driver and passenger’s hip to heel angle is as close to anatomical perfection as is possible. Finally, and critically, a high and upright driving position liberates vital room in the back for rear seat passengers.
The result is a true two plus two, a phrase rather devalued today by being applied to cars with little more than a ledge behind the front seats. In the Continental GT it means a car capable of carrying two adults and two children in comfort for unlimited distances.
Another less obvious but no less important benefit of the Continental GT’s design is the omission of a B-pillar. There are many aesthetic reasons for adopting the pillarless look, but for those inside looking out and particularly those in the back, the unbroken expanse of glass from the front to the rear of the cabin provides a feeling of great space and airiness.
Even the 370 litre luggage capacity has only been achieved through fresh thinking. In cars of this size, it is accepted practice to site the fuel tank between the boot and rear seat, the Continental GT’s fuel tank, however, is under the floor of the car. It’s a tricky piece of design but there’s no doubting the effectiveness of the result.
Not only is there enough boot space to swallow enough luggage for a family fortnight away, if that holiday happens to be to the ski slopes, it will take all four sets of skis inside the car or two pairs of skis and a couple of snow boards. All of this mind, without having to resort to an unsightly and insecure roof rack.
Design Technology
The Continental GT is the first Bentley to have been designed in the virtual world. Using the very latest CATIA-based Computer Aided Design (CAD) programmes, the Continental GT represents a huge step forward in Bentley design technology. With all components existing in the virtual world before a single one is created as a physical property, it is possible to see how each part interacts with all the others, illuminating problems and conflicts that, in the past, may never have come to light until the part had been machined.
This process cuts down development time and costs and enables Bentley’s engineers to design in reliability and consistency in each component. Indeed, one critical aspect of the design work now done in the virtual world enables Bentley to produce theoretically perfect component designs before the Data Control Model (DCM) is made.
The DCM is as close to a mathematically faultless physical model of the interior and exterior of the car as it is possible to have. And it is from this that are taken all the measurements used to specify the tools that will make it when production starts.
Designing this way results not simply in a better built product, it is also likely to be safer . Bentley’s advanced Dynamic Crash Analysis (DCA) capability means much of the trial and error traditionally associated with providing a car with good impact resistance has been bypassed.
Nevertheless it should be understood that DCA, as with all virtual design work will never replace real world test procedure, nor was it ever designed to. Its role is simply to ensure that by the time these tests are conducted, the product is in as good shape as possible to meet each new challenge.
Powertrain
Even before it had been determined how the Continental GT would be powered, two crucial decisions were made. First, the Continental GT would possess a new level of performance that placed it among the fastest road cars on earth; secondly that performance would remain inimitably Bentley. Reconciling these issues would require a great deal of power, but more importantly, huge torque delivered evenly across the rev-range.
But if the car’s packaging requirements were to be met the engine couldn’t take up much space under the bonnet and this is where you discover that the secret of the Continental GT’s interior room is, in fact, its under the bonnet. By choosing the basic architecture of the W12 powerplant used elsewhere in the VW Group, Bentley’s engineers were provided not simply with the opportunity to develop it into a unique Bentley engine, but also to exploit its phenomenal packaging attributes.
Instead of using two long banks of six cylinders, the W12 staggers the cylinders in each bank creating effectively two extraordinarily narrow angle (15deg) V6 engines sharing a common crankshaft and giving rise to the ‘W’ formation.
This naturally provides a phenomenally short engine for its capacity, and frees space that can be reapportioned to the car’s interior. Indeed it is the most compact twelve cylinder engine on the market is even more compact than some V8s.
The W12 formation provided both the power and torque potential that Bentley’s engineers wanted within the compact dimensions they needed.
Once the decision to use the W12 had been made, it was necessary to change entirely its specification to adapt it for the Continental GT.
It was impractical to increase the engine’s capacity beyond its existing 6-litre displacement so Bentley’s engineers decided it should be turbocharged. Forced induction was first used on Bentley road cars in 1929, while turbocharging has been a hallmark of Bentley engine design for 20 years. So twin turbochargers was selected as the preferred means of raising both power and torque. Two KKK turbochargers were chosen and carefully integrated into the under-bonnet package. At the same time, Bentley’s engineering team modified the internal componentry of the powerplant until all its power, torque, emissions, consumption and durability targets had been met or exceeded.
When they were done, the result was a car with 552bhp (560PS/411kW) at 6100rpm. But power is nothing without the torque to back it and this has been achieved not simply by providing 650Nm (479lb ft) of torque but by making it available at just 1600rpm, a speed at which most engines are little more than idling and stays that high up to 6000rpm.
All wheel drive power directed to all four corners
Having created one of the world’s most powerful and responsive engines, it was clear that an equally extraordinary transmission would be needed to cope with it.
The use of all-wheel drive was decided in the earliest stages of the project as it was felt that this new level of power demanded a commensurate level of control. Besides, if the Continental GT was to be exploited by its owners to its maximum potential, it would need to be at home in all environments from the Santa Monica Boulevard to the compacted snow surfaces of Alpine resorts.
Nevertheless, in order to ensure that the right Bentley feel is provided, Bentley’s powertrain and chassis engineers have experimented extensively with the distribution of torque to the front and rear axles. This has been done to provide the Continental GT with all the security of a all-wheel drive system but when appropriate, the added fun factor inherent within a rear-wheel drive layout.
Gearbox: six speed auto - the most advanced of its type in the world
Providing the link between the driven wheels and the engine is a six-speed automatic transmission built for Bentley by ZF and the first of its type to be used in an ultra-high performance coupé. The defining characteristic of this transmission is its ability to lock its torque converter in normal driving, providing the same immediacy of response expected of manual transmissions. Despite this, shift quality is so good that often the most obvious evidence of a gearchange having taken place is the repositioning of the rev-counter needle or centre dash gear display.
Tiptronic actuation means that the car can be used either as a conventional automatic or as a clutchless manual where gear changes take place only on command from the driver, via either the gear lever or paddles mounted behind the steering wheel.
It is a fair observation that a 6-litre, twin-turbo engine does not strictly need six gears. Then again, to look at any element of Bentley performance in terms of need is perhaps to miss some of the point of the marque. It’s true that many Continental GT drivers will spend much of their time allowing the transmission to shift itself, however, Bentley also knows that most of its customers will be enthusiasts who will relish the prospect of flicking up and down the gearbox at the pull of a paddle or the push of a lever. Under the circumstances, six speeds seem entirely appropriate.
Chassis: a car for drivers and passengers alike
Perfecting ride and handling is one of the most complex and difficult areas of car design. For the Continental GT designers this job has been doubly tough, for few cars have been brought to market with a greater expectation of excellence in both areas.
Even so, by starting with well defined and ambitious targets and applying clear thinking and the skills of a 25-strong chassis engineering team to realise them, the Continental GT has been equipped with a chassis that should appeal to sybarites and thrill-seekers equally. The result is a car with firm rather than harsh suspension, impressive resistance to roll, pitch and heave yet compliant enough to ride poorly surfaced roads with absolute equanimity.
The basis of the Continental GT’s chassis strategy is an extremely stiff body, without which, even the most sophisticated of suspension systems can be undermined. To this was applied the latest in suspension technology featuring an innovative double wishbone arrangement at the front - designed to minimise torque reactions through the steered wheels - and a multi-link rear axle behind. Extensive use of aluminium has been made to lower unsprung mass while the entire front subframe of the car is fashioned from stainless steel. Air springs are used at each corner, each one containing its own infinitely adjustable electronic damper.
These electronic dampers do more than offer a few different settings for the driver to play with. Within their set parameters they are capable of adjusting themselves continuously without the driver ever being aware of it.
Electronic stability systems: Unintrusive and at the discretion of the driver
Naturally both traction control and the latest Bosch Electronic Stability Programme (ESP) are fitted, though they can be disabled at the discretion of the driver - Bentley has no desire to dictate how the Continental GT is driven. The secret to understanding their function is to see them as additional to the Continental GT’s dynamic behaviour, rather than as an essential ingredient in keeping a car of these capabilities safe.
The Continental GT is capable of monitoring a whole range of dynamic attitudes such as lateral acceleration, individual wheel speeds, throttle position and brake pressure. No car can defy the laws of physics and there are certain extreme conditions that even ESP will be unable to guard against, but as an extra line of defence for the unfortunate driver caught out by unexpected circumstances, its safety value is real and evident.
That said, as the most sporting road-going Bentley since the R-Type Continental, the Continental GT is a driver’s car through and through and Bentley’s chassis engineers - enthusiasts all - have been acutely aware that not only must the chassis have the raw ability to match perfectly the engine’s phenomenal output, it must provide it in a way that indulges and engrosses its driver.
To this end, a huge amount of work has been done analysing spring, damper and anti-roll bar rates to ensure the car has the right sporting stance on the road. Exhaustive testing of steering geometries has been undertaken to eliminate unwanted torque reactions, and also to provide the appropriate amount of ‘feel’ in the chassis. In particular, the Servotronic rack and pinion steering has been evaluated to ensure it delivers the right response in terms of steering, but also feedback to the driver.
Brakes: ensuring the Continental GT stops as well as it goes
Braking will be provided by all new, ventilated and grooved disc brakes at each corner featuring the latest Bosch anti-lock system with Brake Assist and Electronic Brake Force Distribution.
Once all the specification of the chassis had been determined, the Continental GT was put through the most rigorous real world evaluation programme of any Bentley in history, a process that continues to this day. From race tracks such as the famed original Nurburgring to mountain passes and sinuous switchbacks all over the world, the Continental GT is being tested and re-tested to fine tune its exceptionally promising chassis specification to provide ride and handling standards that don’t merely rise above the class standard but define it.
Safety: prevention is even better than cure
Naturally the Continental GT is equipped with the full suite of passive safety equipment. As well as possessing exceptional front, side and rear deformation characteristics on impact, there are two front airbags, four side airbags and two side curtain bags that, unusually for a coupé, run along the full length of the cabin. Seat belt pretensioners are used for all four seats.
Of course avoiding the accident in the first place has always to be preferable. To this end the Continental GT is specified like few others in the market. All-wheel drive, when correctly exploited, has colossal safety advantages in adverse conditions, while the latest traction, stability and brake control systems offer further opportunities for drivers to extricate themselves from danger. And of course there is the powerful engine and its ability to keep time spent on the wrong side of the road during overtaking to an absolute minimum; and should you ever have to accelerate away from trouble, few will do so more quickly than this.
Positioning: a unique opportunity to bring Bentley to a wider audience
At its core, the Continental GT is the result of just three things: first a deep seated emotional desire within Bentley to create an all new compact coupé. Secondly there is VW’s provision of the financial wherewithal not simply to create the car, but to do so in a way that gave Bentley a design, engineering and manufacturing lead over all potential rivals. But the Continental GT still would not have been possible without a concrete business case for producing such a car.
This case is satisfyingly straightforward and hinges on a clear gap in the upper luxury coupé market. In the past those looking to buy in this sector have had a straight choice between two differing breeds of car. The first was an uncompromising sportscar with minimal or no rear seat space and miserly luggage provision. Alternatively they could choose a rather more accommodating coupé, but suffer a commensurate reduction in driving enjoyment. Those who crave true supercar performance, response and style but need the flexibility of a car that seats four, carries their luggage and can be used everyday for all purposes, only the Continental GT will suit.
Although most of the 3200 plus people who have put down deposits for a Continental GT possess a number of cars, a significant proportion are buying to use the Bentley as their primary vehicle . Some 75 per cent of Continental GT customers are new to the marque.
The profile of the typical Continental GT buyer is also subtly different from the traditional Bentley customer. They tend to be younger, with an average age of under as opposed to just over 50 years. Men still buy many more than women, but their majority is decreasing from 96-99 per cent to a slightly more balanced 85-90 per cent. They are more typically owners of their own business rather than directors of public companies.
Progressive but utterly faithful to its heritage
In all physical senses, the changes the Continental GT has brought to Bentley have transformed the company beyond recognition. The car itself and the renewed factory in which it is being built mark the dawn of a new and thrilling era for the marque.
But in a less tangible but no less important way Bentley is actually returning to its heartland values, as defined by the founding vision of WO Bentley. The strength of any brand in this sector is the thought that created it, and while there were times in the distant past when that vision had become little more than a nostalgic fairytale, now and increasingly it resonates through the walls of the Crewe factory.
WO’s proposition is as compelling today as it was 84 years ago. He would combine cutting edge design with outrageous performance and superlative craftsmanship to create a potent and unique motoring experience. Moreover it would have a purpose that took it beyond mere recreation and turned it into something of real use and significance.
And while it would offer great comfort and unquestioned luxury as it went about its daily business, so also it would possess a thinly veiled ability to turn into something very special at any moment.
He also understood that a good car will always be greater than the sum of its parts. A car may look mightily impressive on paper, but it all still has to gel on the road to create an authentic Bentley experience, one that makes the driver feel in his or her element whatever the conditions.
A true Bentley is a car that goes beyond satisfying the needs of its customers: it should exceed all expectation and do so routinely; it should possess an ambience beyond mere description, one that has to be experienced before it can be appreciated. Above all it should blend apparently conflicting interests as if they were made for each other, proving thrilling yet cosseting, imposing but subtle, a car with great presence but lacking entirely in ostentation. These are precisely the qualities the Continental GT - a true British Grand Tourer - has been styled, engineered and designed to provide and the result is a car of which WO Bentley would be justifiably proud.
Bentley Continental GT - Technical Details
Highlights
* The fastest, four seat production car in the world
* Twin turbo, 6-litre, W12 engine developing 552 bhp (560PS) and 650Nm of torque
* Top speed of 198mph (318km/h)
* 0-60mph in 4.7sec (0-100 km/h in 4.8 sec)
* Maximum torque developed at just 1600rpm and comfort to 6000rpm
* Six speed, paddle operation automatic transmission with full lock-up
* Four-wheel drive with central Torsen differential
* Computer controlled air-sprung multi-link suspension front and rear
* Largest brakes of any car ever put into production
Introduction
Now that the Bentley Continental GT has made its world debut, Bentley Motors is now in a position to reveal the full technical specification of what is not only its fastest road car, but also the fastest, four seat car in the world. Two figures alone would seem to say it all: it accelerates from 0-60mph in 4.7sec (0-100km/h 4.8sec) and reaches a top speed of 198mph (318km/h). In fact such bold statistics barely scratch the surface of the Continental GT’s true capabilities.
The aim from the start of the Continental GT project was to create a car with an unrivalled performance envelope, so that it would not only be quicker and more powerful than any rival on paper, but that also these extraordinary talents would be able to be used safely and to the full in the real world. The Continental GT is not and never was about theoretical performance potential - every aspect of its ability has been specifically tailored so that it is not just possible to access its performance, it is easy and natural.
Moreover, the Continental GT concept also dictated that the resulting car would recognise that, though we would all wish otherwise, road conditions in all markets mean that frequently its owners will not be able to make use of its full potential. Indeed in some regions traffic conditions are such that being able to extend such a car is more of a rare treat than an everyday occurrence. Which is why in addition to being able to thrill its occupants at a moment’s notice, the Continental GT is also configured to comfort and cosset them the rest of the time - in the tradition of a true British Grand Tourer.
The Bentley Continental GT is the first product designed entirely under the patronage of the Volkswagen Group and a £500 million investment in the marque has enabled a transformation of the site at Crewe. This made it possible for the Continental GT to be designed, engineered and assembled on site.
The investment has also made it possible for Bentley to recruit over 400 new staff to Crewe, giving Bentley greater independence and control over its future than at any time since it first passed into proprietary ownership in 1931.
Engine
The heart of the Continental GT is its 5998cc, four camshaft, 48-valve, twin turbocharged W12 engine. It can now be revealed that its power output, hitherto quoted as ‘in excess of 500bhp’, is in fact 552bhp (560PS) (411kW) at 6100rpm. Maximum torque is 650Nm (479lb ft) which may sound an impressive enough statistic in isolation but its true significance only become apparent when you learn that it is generated at just 1600rpm. Typically, a performance car engine will force the driver to wait until it is spinning at between 3-5000rpm before it will deliver maximum thrust; in the Continental GT it’s all there at barely more than idling speed. No other car in production makes its torque so instantly accessible.
But this just the start of the story for this engine has other claims to fame beyond its headline-grabbing outputs. Its exterior dimensions, for instance, make it the smallest 12-cylinder engine currently in production, despite its considerable 6-litre displacement. The block is just 513mm long, 715mm high and 710mm wide. This has been made possible entirely by its ‘W’ formation where instead of arranging the cylinders in two long rows as you would in a conventional V12 configuration, each bank of cylinders is actually staggered, effectively creating two V6 engines mated on a common crankshaft. The angle between the two main banks is 72deg, that between the staggered cylinders just 15deg. The result of this is an exceptionally compact motor, a trait that brings advantages in many areas. Clearly it helps hugely with weight distribution as a geographically small engine is easier to locate nearer the centre of the car. This in turn helps the overall packaging of the car and, in particular, its frontal crash performance, a crucial consideration in a Bentley which has a short front overhang as one of the main features of its design language.
It is no secret that the basic engine architecture has been supplied to Bentley from its parent company, the Volkswagen Group, but by the time Bentley’s powertrain team had finished re-engineering it to an exclusive specification for the Continental GT, it could be truly considered a unique engine in its own right.
Clearly the major engineering challenge was to adapt the engine to accept forced induction, a process that required major re-engineering of the block, the replacement of many internal components and all new inlet and exhaust manifolds. The result would have to cope with a rise in output from 420bhp in standard form to 552bhp once installed under the bonnet of the Continental GT.
The engine features special pistons, specifically designed for the Continental GT in order to deliver the desired compression ratio of 9.5:1, a phenomenally high figure for a turbocharged engine. The engine also features seven main bearings, pent-roof combustion chambers and variable valve timing on both inlet and exhaust valves. The timing is infinitely variable within its fixed range, which is some 52 degrees on the inlet camshafts and 22 degrees on the exhaust camshafts.
A huge amount of work was also undertaken to make sure the Continental GT could use very efficient air to air intercooler. Fitting them within the already cosy confines under the Continental GT’s bonnet was not the matter of the moment, but Bentley’s engineers regarded their inclusion in the specification as not negotiable and, after several months work, they were integrated into the under bonnet package.
The Continental GT also uses a dedicated exhaust system, using two six-into-one manifolds. Much attention has been paid not simply to ensure the exhaust provides maximum efficiency, but also that its sound is appropriate to the fastest Bentley road car in both tone and volume.
The turbochargers are made for Bentley by renowned specialists, KKK, and need operate at only the comparatively conservative boost pressure of 0.7bar to provide the Continental GT with its headline performance. Given this, the existence of maximum torque at 1600rpm and the engine’s 6-litre capacity and it’s easy to see how turbo-lag, the sole undesirable side-effect of this variety of forced induction, has been effectively removed from the equation. As with all Bentley-designed powerplants since the birth of the company in 1919, smooth power is not something you need to wait or ask for - it is there, at your disposal at every point of the rev-range from idle to its 6100rpm red-line.
Controlling all this power is Bosch’s state of the art ME 7.1.1 engine management system which comes complete with two throttle bodies, exhaust gas temperature regulation, boost pressure regulation, two air mass sensors, four knock sensors with adaptive learning and the latest ESP 5.7 electronic stability programme. Ignition is achieved without the need for a distributor, thanks to each cylinder being provided with its own coil. The engine is fully compliant with future Euro IV emissions regulations and has been calibrated to run on standard 95RON octane pump fuel.
Such is the power of the Bentley Continental GT’s powertrain that Bentley engineers took the decision to reinforce its already substantial engine mounts with Kevlar bindings to make sure it does not move even under the most extreme circumstances.
Powertrain testing
The engine in the Continental GT has undergone some of the most gruelling and exhausting test procedures of any engine in order to ensure that it can be depended upon to accommodate all and more than any owner could ever need. Naturally prototypes have and continue to rack up millions of miles in some of the hottest, coldest, driest and most humid places on earth, but perhaps no single test illustrates the relentless pursuit of engineering perfection than those tests performed with the engine out of the car and sitting on a bench.
Perhaps the most eye-opening of these is a test where the engine is switched on and revved to maximum revolutions (6100rpm) from cold and then left there, not for a few minutes or even a few hours. It is left to run at maximum speed for 100 hours or, put another way, over four Le Mans in a row.
Another test puts the engine through an advanced programme of cyclical accelerations, decelerations and steady state running at all points in the rev range for 500 hours non-stop or, to put that it perspective, just four hours short of three weeks.
The engine has also been exposed to prolonged thermal shock cycling where internal temperatures are swiftly brought to a peak whereupon its coolant is replaced by ice-cold fluid in order to induce the swiftest possible drop in temperature before the engine is re-heated up to maximum temperature again and the process is repeated.
Transmission
Not many gearboxes are capable of handling the extraordinary torque loadings that the Continental GT engine is able to produce and none so far fitted to a luxury coupe has had the benefit of six gears. Yet with the help of its partners at ZF, that is exactly what Bentley has provided for the Continental GT. Designated 6HP26, the new gearbox is the most advanced of its kind in the world, offering not only six ratios but also the ability to lock up its torque converter in every gear, providing effectively manual gearchanges via either the gear lever or steering wheel paddles.
The gearbox itself is exceptionally light and compact, given the torque it must handle, indeed it has almost 30 per cent fewer components than a conventional five speed automatic, decreasing weight and improving both reliability and efficiency. Though variants of this gearbox have been supplied by ZF to other luxury car manufacturers, that used by the Continental GT is distinguished by being adapted for use with a four-wheel drive transmission and has been further modified for use in the Continental GT.
Not only does the Continental GT carry bespoke gearing, tailored precisely to the unique torque characteristics of the engine and the car’s exceptional top speed, it has also been fundamentally redesigned for installation in the Bentley, placing the front differential ahead of the torque converter in order to push the front wheels as far forward as possible, creating a minimal front overhang, an inimitable Bentley design trait. Direct drive equates to 22.7mph (36.5km/h) per 1000rpm which, with a 0.691:1 top gear ratio, gives 32.85mph (52.86km/h) per 1000rpm. At first this may appear a relatively long-legged ratio, after all the Continental GT will sit at the UK national speed limit (70mph) with just over 2100rpm on the rev-counter. In fact, and in keeping with the car’s extreme sporting aspirations, this ratio has been chosen to ensure that maximum power and maximum speed coincide as closely as possible.
All-wheel drive
Pointing the power in four directions was part of the original strategy for ensuring the Continental GT would remain, safe, usable and enjoyable in all weather conditions routinely found around the world.
The system used employs a central Torsen (TORque SENsing) differential and a free differential on each of the front and rear axles. Both the front and centre differentials have individual cooling radiators.
After exhaustive investigation and a substantial test programme of available alternatives, Bentley’s engineers decided to divide the drive equally between the front and rear axles, giving a conventional 50:50 torque split. This is the combination that was found to be best at providing not simply the safety demanded of a car with this performance potential, but also the most favourable handling response.
Naturally this front to rear ratio is infinitely variable according to available grip and the Torsen differential together with the 4 wheel asr can sense slip of less than one per cent and act accordingly, apportioning the engine’s torque to either the front or rear axle. It would, in reality, take exceptional conditions for this to happen such as both wheels of one axle being on black ice but in more conventional circumstances the Torsen differential will always be able to optimise the torque loadings between the axles.
Thanks to the Continental GT’s advanced electronic stability programme, the need to equip each axle with a limited slip differential is obviated. When slip is detected at one wheel, the ESP system can apply the brake individually to that wheel and allow the torque to be transferred across the axle to the tyre with the most grip. In normal use this system acts entirely unobtrusively but it does, in fact, possess the ability to keep the Continental GT moving forward when traction is available to just one of its four wheels. It is true that luxury coupés rarely find themselves in these conditions but it is also true that this is because their hitherto practical limitations have tended to keep them from places where such circumstances are more likely to occur. But with all-wheel drive, advanced traction and stability systems (not to mention its spacious interior, large boot and ski-friendly through-loading facility), the Continental GT will easily take its occupants to remote mountain resorts where no other luxury coupé would dare to follow.
Electronic Safety Systems
Bentley takes the responsibility of putting a 200mph car on sale to the general public extremely seriously and, in addition to the clear traction advantage afforded by its all-wheel drive hardwear, Bentley’s engineers have been working just as hard to make sure the software is there to back it up too.
ABS anti-lock brakes, HBA (Hydraulic Brake Assist) and EBD (Electronic Brakeforce Distribution) in conjunction with the Continental GT’s varied array of other defences designed to keep the car under control.
These include ASR traction control that employs the ABS sensors to detect when traction is lost at either end due to a combination of a low grip surface and an excessive application of power. Under these circumstances, the ASR will instantaneously cut the power until traction is restored.
As mentioned earlier, the Continental GT also features the latest Electronic Stability Programme (Bosch 5.7). This ESP system, which necessitates the use of a fly-by-wire throttle, operates by a system of sensors analysing a number of different parameters such as speed, throttle opening, steering angle and the car’s yaw and pitch. When one of these parameters is breached, indicating a possible or impending loss of control, the ECU is informed and appropriate action is taken. Depending on the nature and severity of the situation this might amount to little more than throttle modulation or it could involve the targeted application and release of individual brake callipers until full control is restored.
The final weapon in this armoury is MSR drag torque control. This is an intermediate, electronic control system, designed to intervene before a potential loss of control is address by ESP or ABS. During deceleration it modulates engine braking to ensure deceleration is consistent, swift and helps remove the possibility of a wheel locking when the transmission changes down on a reduced grip surface.
Body Structure
It is widely understood that whether your ultimate aim is fine handling, exceptional ride quality or any blend of the two, the fundamental essential quality that must be provided before all others is a rigid structure. Without this firm foundation, the good offices of finest suspension systems and tyres will be irretrievably undermined. The trick is to remove as far as possible the frequency at which the body will start to vibrate from the frequencies of the disturbances introduced all over the body by everyday life on the road. The stiffer the bodyshell, therefore, the less the body will vibrate in sympathy with road imperfections and the better suspension will be able to work.
It is also true that the potentially positive effect of adding stiffness to a car’s bodyshell is entirely negated if the weight of that shell rises in proportion to the additional stiffness gained.
When presented with a brief for the Continental GT, Bentley’s engineers were told that nothing less than exception torsional rigidity would enable the Continental to meet its dynamic targets. And the challenge they faced was providing such stiffness to a car with such a long wheelbase relative to its overall length and one which, thanks to its pillarless design, lacks a B-post between the front and rear side windows.
The first step to realising its targets was taken in the virtual world. Every single component on the Continental GT was designed on a computer and integrated into three dimensional digital models of the car. Using the latest Computer Aided Design (CAD) technology alongside Digital Mock Ups (DMU), Finite Element and Dynamic Crash Analysis (FE and DCA), Bentley’s engineers were able to predict, analyse and enhance the Continental GT’s structural integrity long before the first prototype was built.
Next, Bentley’s engineers turned to adhesive technology. Adhesives have played a vital role in aircraft and aerospace technologies for some time (where they are used, for instance, to attach wings to aircraft fuselages) but it is only now that their full potential is being realised in the arena of car design. If understood correctly and used properly, adhesives can bring huge improvements to a body structure’s rigidity with a minimal increase in weight. Adhesives are therefore used throughout the structure of the Continental GT, but particularly where there are long seals, such as around the door apertures.
Another emergent technology employed for the first time by Bentley is laser-welding. This process is expensive but, by introducing a new level of control into the welding process, it allows a considerable extra degree of strength to be introduced into each weld while, at the same time, ensuring minimal wastage and therefore saving weight.
Chassis
The Continental GT is without doubt the most sporting Bentley since the original company went into liquidation in 1931, but it would be no kind of Bentley at all if it was tuned to provide invigorating handling at the expense of a bone-jarring ride. The Continental GT is as its name describes, a long distance British Grand Tourer and while capable of being enthralling to drive, it also recognises that most of the time it will be driven on motorways or in towns when handling response will always be of secondary interest to overall ride quality.
Therefore, in the spirit of no compromise it was laid down that the Continental GT had to be as comfortable as it was quick, as responsive and it was restful. This was no mean feat to achieve and Bentley’s engineers had to turn to one of the most sophisticated suspension arrangements ever configured to realise it.
Suspension at the front of the car is provided by twin upper and lower arms that converge as in a conventional wishbone arrangement but, in fact, never meet. The system is described as a ‘virtual king pin axis’ arrangement because the pivot point, where the arms would meet eventually meet is actually in the plane of the wheel rather than at a point in-board of the wheel.
The problem with the conventional system is that the torque loadings will only not be felt by the driver if they are equal either side and therefore cancel eachother out. But if one wheel slips on a low friction surface, the loadings become unequal and this is fed straight back to the driver through the steering wheel. But by having the axis in the plane of the wheel, the torque is not created in the first place. The result is a car capable of putting phenomenal amounts of power through its front wheels without risking the dreaded ‘torque steer’ that would otherwise afflict it.
The rear suspension of the Continental GT is a multi-link arrangement designed to promote stability under all conditions be they braking, acceleration or cornering. Using trapezoidal wishbones and tie rods to give the rear tyres a firm foothold on the tarmac regardless of loading, this system plays a critical role in assuring that the Continental GT meets its targets for both ride and handling.
Much of the suspension at the front and rear, including all control arms, are made from aluminium that not only helps reduce the weight of the car but, critically, also keeps unsprung mass to a minimum, helping to achieve optimum ride quality.
Self-levelling air suspension has also been specified as standard equipment for the Continental GT. Much more expensive than a conventional steel spring, air suspension brings many benefits that would otherwise have been denied to the Continental GT. Air suspension works very simply with air-filled rubber bellows acting within a sealed tube with a concentric damper in the middle. As the wheel moves up, it compresses the air in the bellows which then offers resistance and thereby a springing effect.
One of the main advantages of air suspension over a steel spring is that the laws of gas dynamics mean that if you increase the mass on the axle, it compresses the spring further so the natural frequency of the car bouncing on its spring is are held nearly constant whereas in a conventional system the frequency would become lower. This can be exploited to ensure that the car never suffers from that stodgy feeling that affects all steel sprung cars when they are heavily laden. In addition, the pressure acting on the spring is uniform across the entire strut whereas any conventional spring will inevitably be subject to some side loadings.
Another crucial benefit of air springs is the scope it provides in being able to tailor the car’s ride characteristics. By carefully shaping the bellows, you can ensure that as they go up and down, they also go in and out effectively varying the spring rate as they do. The further in they go, the less air they contain and the softer the springing will consequently be. The bellows on the Continental GT are therefore designed to be quite narrow at the centre of each wheel’s movement so that the suspension is relatively soft about its central point with obvious benefits in ride quality. Then, as the springs are compressed or expanded through acceleration, braking or cornering, the bellows widen to accept more air, firming up the ride and providing an extra level of control precisely when it’s needed.
The final primary advantage of air suspension is packaging. If you were to ask a conventional spring to provide the same low frequencies that the Continental GT can achieve, there are only two ways of achieving it. You can either make the spring very long at which stage it can become unstable under compression, or you can shorten and widen it, bringing inevitable packaging problems. Using an air spring has allowed Bentley’s engineers to allow for a much wider range of frequencies within a given space.
Air springs also allow Bentley to lower the ride height of the Continental GT at speed, optimising its aerodynamic performance. Currently the suspension is programmed to lower the car by 15mm at 100mph (161km/h).
The dampers used on the Continental GT are continuously and infinitely variable and the most sophisticated yet seen on a Bentley. Controlled entirely by computer, the dampers possess the ability to change their characteristics many times during a single ‘event’ such as a wheel moving up and down over a bump.
The electronics are so sophisticated they don’t merely look at a force and react accordingly - they monitor the entire car. One example of how this works to the benefit of the Continental GT’s ride comfort is that the computer can decide to let a wheel move to accommodate a single event if the car itself is in a fundamentally stable state. So if a bump is encountered, the damper will allow the wheel to travel upwards in the normal way. If however the body, let us say, is already moving downwards in reaction to an immediately prior event, the computer will analyse the relative movement of body and wheel and, if need be instruct the dampers to stiffen, thereby checking the upward motion of the wheel towards the descending body.
The overall set-up of the suspension has been configured to make the Continental GT an inherent mildly understeering car in steady-state cornering. This approach has been adopted primarily because Bentley believes that oversteer is a condition that should only ever arise at the driver’s command. A car with low levels of natural understeer will, when the limit of adhesion is finally broached, gently start to run wide in a corner, a condition that can easily be cancelled by a simple lift of the accelerator. Bentley believes this is undoubtedly the safest and therefore the only responsible route to take.
That said, Bentley is equally aware that most Continental GT drivers will be of the ‘press on’ variety and have made it possible for the engine’s torque to be used to overcome understeer in certain conditions, allowing the car to adopt a stance of neutrality or even mild and controllable oversteer, regulated by the ESP system.
Steering
The Continental GT features rack and pinion steering with speed sensitive Servotronic power assistance. The rack and pinion was chosen as it is the most precise form of steering available and offers great feel to the driver, an essential consideration in a car such as this. The rack has been designed with a fixed ratio so as to provide maximum linearity and consistency across the locks and has been equipped to give excellent feel both on and off-centre.
Wheels and tyres
The Bentley Continental GT uses the same size wheels and tyres on both the front and rear axles after extensive investigation revealed this to be the optimum solution for a front engined car such as this when fitted with four-wheel drive. Two wheels will be available with 19in rims as standard and 19in split rims as an option. Tyre size is 275/40R19. These sizes have been chosen not only because they fit the ride and handling requirements of the Continental GT, but also because either can be fitted without changing the overall gearing of the car.
Brakes
The Bentley Continental GT is equipped with the largest brakes ever to be fitted to a standard production car. The ventilated front discs have a 405mm diameter (15.9in) and are 36mm (1.4in) thick, making them wider than the actual wheels of most production cars. Ventilated discs are also used at the back, this time of 335mm width (13.2in) and 22mm thickness (0.9in).
These brakes are not available on any other car, indeed they were created specially for the Continental GT by Teves to a specification laid down by Bentley. Teves were also responsible for their appropriately huge callipers.
The reason Bentley chose a brake specification beyond that yet offered on any production road car is simply that it holds the conviction that the Continental GT should stop as well as it goes.
The energy contained within a fully laden Continental GT travelling at around 200mph is naturally considerable. Through months of real world tests and computer analysis it was determined that nothing less than the finest braking system in the world would be capable of delivering not only the retardation Bentley required, but also the ability to do so again and again with no fade or loss of performance.
This formidable braking hardwear is also backed by a comprehensive software package. In addition to Hydraulic Braking Assistance (HBA) and anti-lock (ABS) and drag torque control (MSR), the Continental GT also comes with Electronic Brakeforce Distribution (EBD). This system monitors the level of grip available to each tyre and apportions braking force accordingly. This not only helps reduce stopping distances but also greatly enhances the feeling of control enjoyed by the driver under heavy braking.
Aerodynamics
The role played by aerodynamics in modern car design has advanced considerably from the age where making the smallest hole in the air is the most important consideration. Aerodynamics affect almost all areas of the car and without both the exploitation as well as the avoidance of the airflow, no modern car will realise its full potential.
And the faster the car, the more important are its aerodynamics, not simply to realise such speeds, but also to keep the car stable and its underbonnet temperatures cool.
The Continental GT’s shape can be said to be a thoroughly modern interpretation of classic fastback design and as a result it boasts the enviably low drag coefficient of just 0.32. However one of the historical drawbacks of such a shape is that if the airflow is allowed to spill off the back of the car unchecked, it creates classic conditions for encouraging rear-end lift. This could potentially change the balance of the car, alter the effective weight distribution and create unwanted instability.
To counter this, the Continental GT has two specific aerodynamic devices, neither of which is immediately visible to naked eye when the car is stationary, that takes the potentially threatening airflow and turns it to the car’s advantage.
The first is a rear spoiler that lies across the base of the rear windscreen and deploys once the car is travelling at above a certain speed. This effectively interrupts the flow of air coming off the back of the car and uses it actually to push the car harder onto the road rather than let it create unwanted lift. Working in close conjunction with the rear spoiler is a diffuser underneath the back of the car, which not only contributes greatly to the car’s overall stability, but also helps extract air from underneath the car and this reduces drag
Another crucial responsibility of the aerodynamics team is to ensure there is sufficient airflow to and from all heat-generating components. One look at the displacement of the engine, its power output and the tightly packaged under-bonnet area gives some idea of the challenge involved. But in fact, the cooling requirement is that the Continental GT should be able to run fully laden in 40°C ambient temperature and at maximum speed until it has drained its fuel tank - a tougher test by far than will ever be replicated by any owner on the public road. To achieve this, thousands of hours were spent creating and studying computational fluid dynamics data (CFD) to ensure the correct airflow to all areas under the bonnet and to the brakes. In those areas where this flow in inherently compromised, (such as for both the front and central differentials) individual cooling radiators have been installed.
Acoustics
In many luxury cars, the primary acoustic aim is to reduce noise intrusion from the wind, road, suspension and powertrain to create the greatest level of refinement possible. But when you are charged with creating an all-new Bentley some rather more subjective and no less important considerations need to be accommodated. In short, the Continental GT needs not only to look like a Bentley from bumper to bumper, it needs to sound like one too.
Bentley’s acoustic engineers have been at work since the very start of the Continental GT project deciding first how the car should sound and then determining how that sound should be achieved. So important is their work that they were able to influence the design of both the intake and exhaust manifolds to make sure a true, unique and instantly identifiable Bentley soundtrack would greet the occupants. Bentley also carried out extensive customer research among existing Bentley owners and prospects who will be new to the marque, in conjunction with benchmarking the sound quality and quantity of other luxury sportscars.
The sound of the Continental GT is therefore deep, smooth, muscular and inspiring.
In keeping with its Grand Touring aspirations, the Continental GT has also been configured to be an extremely refined car. In pursuit of this, the design has been helped by the provision of an astoundingly smooth engine and a very rigid bodyshell. These have provided Bentley’s engineers with a platform that already possesses minimal noise, vibration and harshness (NVH) characteristics.
Beyond that, the task was to investigate every component, every system and the car as a whole to make sure no unnecessary NVH sources were inadvertently designed into the car. This work was carried out first in the virtual world and was then incorporated into the wind tunnel programme.
It continued on Bentley’s own Hydropulse four poster rig at Crewe which replicates road conditions without the potential for inconsistency caused by changes in weather and traffic and, of course, on real roads around the world to ensure that every part, from the smallest seal to the body structure itself, contributed to making the Continental GT the most refined car in the marque’s history.
Use of Electronics
There are many elements of the Continental GT’s specification that deserve to be described as extraordinary but perhaps none more so than its use of electronics.
Consider these points: Each Continental GT contains approximately two miles (3.2km) of cabling and the main wiring harness alone weighs over 50kg. A Continental GT also contains 70 microprocessors. A PC has just one. It has 35 individual control units - black boxes by another name - and they all talk to one another via three Control Area Networks (CAN) working at 500 kilobits/sec, and one superfast fibre-optic serial network operating at 4.2megabits/sec. A conventional low-speed serial network functions at just 9.6kilobits/sec. At any one time, the quantity of CAN messages in use around the car can number over 2000.
This electronic dialogue is important because all the various features on the car need to know what the others are up to as rarely does one have no impact on any of the others. For instance if the windows are being lowered, this is information that is likely to be of interest to the security systems. Another example is the information provided by the self-levelling sensors in the suspension is also of use to systems such as the ESP to help it constantly monitor the car’s progress and the automatic headlight levelling to keep the beam at a constant pitch.
This system also helps simplify operations as it saves the same information being gathered by independent systems. One example of this is that responsibility for measuring vehicle speed has been allocated to the ABS sensors but this information is also used by the powertrain network for the engine management and transmission.
The easiest way to understand how the Continental GT’s internal communications are configured is to imagine the networks as a huge notice board upon which all contributing systems post information as they receive it. Once there it can be seen by all other systems and, if need be, acted upon accordingly.
Conclusion
As can be seen, the Bentley Continental GT is one of the most sophisticated cars ever to be produced, breaking new ground in several areas while offering a level of performance for a four seat car that is unique in both quantity and quality. And while Bentley’s engineers have made use of many processes and components that already existed within the Volkswagen Group, the result is as much a Bentley as it would be if it had gone to external suppliers.
Technologically the car is a tour de force and a mobile showcase for the technical capability now resident in Crewe. It shows that Bentley has both the backing and the ability to take on the world with a product unlike any other in the market place - one that still benefits from the unrivalled understanding of handcraftsmanship that has been handed down the generations at Crewe, but one that also sits right at the cutting edge of 21st century knowledge. Not once during the development of the Continental GT, has this blend of the traditional and advanced worked with less than total harmony. Using techniques both new and old, they have produced a car that does not need to look back because it knows already exactly from where it has come.
When, 75 years ago (1928), WO Bentley announced what would become his most fabled car, the Speed Six, he saw no problem in producing a design that could be both a limousine and a Le Mans winner, both disciplines in which the car went on to excel; and while the Continental GT cannot claim to cast its net quite that wide, the same principle of creating a car with the ability to both cosset and enthral is the same now as it was then. Then it created one of the world’s few automotive legends; it is not for Bentley Motors to make such lofty claims for the Continental GT - all we would say is that it is a car of which we are inordinately proud and can only hope that, could he see it, it is also a car to which WO would be equally proud to lend his name.
Crewe factory gears up for Bentley Continental GT
The Bentley factory at Crewe has been described as ‘the largest showroom in the world’. For years, owners and prospective owners from all over the world have come to see the hand-crafted cars slowly taking shape and to enjoy the unique experience of talking to the very people who build their Bentleys.
But the launch of the Continental GT poses a new set of challenges for Crewe. The W12-engined, all-wheel drive Continental GT is itself one of the most complex and advanced machines on the road. The production team at Crewe had the task of producing this exceptional new British Grand Tourer to benchmark quality standards, in greatly increased numbers, without losing the human judgement, core skills and customer interaction which form such a large part of a Bentley’s appeal.
The result is not so much a new production line as a new factory. Every element of the production process has been re-designed, in close consultation with team leaders among the 1200 Crewe associates who work in Bentley production. Being part of the Volkswagen Group, Bentley Motors has benefited from an overall £500m/Eu800m investment programme, with Eu91m being spent directly at the Crewe site. Although the largest-ever investment made at the Crewe factory, this was no ‘blank cheque’ approach. The manufacturing engineering team took as their mission the achievement of world-class quality levels, on time, at optimal cost and - crucially - in a socially responsible manner.
Hand built Bentley engines
From the earliest days of Bentley in Cricklewood, under the critical eye of Walter Owen (WO) Bentley, the design and build of the Bentley engine has always been the heart of the marque, and the Continental GT is no exception. In WO’s day, coachwork was outsourced to a number of specialist coachbuilders, whilst today the Continental GT’s body is produced at VW group production facilities in Mosel, Germany, benefiting from economies of scale. But the twin-turbocharged W12 Bentley engine for the Continental GT is, quite properly, built up from the base casting on site at Crewe.
The engine’s crankcase and an entire ‘kit’ of parts for each engine is mounted on an Automatic Guided Vehicle (AGV), which is self-powered and equipped with laser-guidance tracking that follows defined black lines painted on the floor. The AGV visits each of the 16 assembly workstations in strict sequence, and remains at each for exactly 17 minutes. It thus takes four and a half hours to process and test a Bentley engine with a total assembly time of 15 hours per unit.
Each engine is hand-built and the judgement of the skilled craftsmen who assemble it is used to select matched parts that balance exactly: crankshaft to main bearing, crankshaft to conrod bearing and crankcase to pistons.
The DC electric power tools used to torque up the engine’s fastening nuts and bolts are linked to the AGV and its on-board monitoring system. As each bolt is tightened in sequence by the engine craftsman, the DC power tool ‘reports’ back to the monitor that the correct torque has been achieved. There can be no possibility of ‘missing’ a fastener or failing to tighten it to the required torque - until the task is complete, the AGV will not move to the next station.
Every Continental GT engine is first turned during a cold test to check that all is well, before being connected to the hot test rig and fired up for the first time. When production is under way each engine will be tested for at least two hours, with 10% of engine production being run for up to 48 hours under full power to validate the integrity of the assembly process.
Assembly Line - from body shell to “marriage station”
As a Continental GT proceeds along the line and through the various workstations, its panels protected by tailored covers with the famous winged ‘B’ Bentley emblem, it slowly takes shape as a finished Bentley. In the Chassis 1 area, the wiring, hydraulic pipes, lights and HVAC (heating, ventilation and air conditioning) systems are assembled to the body shell. From there the shell passes to the ‘marriage station’, where it meets up with the engine, subframes and wheels, and becomes recognisably a Bentley Continental GT. Within the engine bay of the Continental GT the compact but massively powerful W12 engine and transmission is an exact fit, with not a millimetre of excess space. Fluids for hydraulics, HVAC, brakes and coolant are then added, but not before each system in turn is tested for leaks, first under pressure, then under vacuum. If no leaks are detected, the vacuum is then used to draw the fluids through into its various reservoirs and pipes.
Wood - new techniques reinforces traditional skills
The unbleached fine wood veneers of a Bentley’s fascia, console and waistrails are an essential part of the character of the marque, and Crewe’s expertise in wood makes it unique in world automotive production.
Naturally, Bentley’s woodshop still uses only the finest sheets of hand-selected veneer, but in cutting the veneer to shape, new technology has helped to cut waste and improve quality. Laser cutters, accurate to 0.25mm, cut the veneer sheets to shape - Bentley still insists upon veneer that is a full 0.6mm thick, rather than the industry norm of 0.4mm.
Bentley’s fascia panels have always displayed ‘mirror-matched’ veneer patterns, with one side exactly reflecting the other; only possible when two adjacent wafer thin leaves have been taken from the same tree. The Continental GT is no exception, and the signature join of mirror-matched leaves is ’stitched’ together at the rear with a zigzag glue weld.
Between the substrate panel and fine wood veneer comes a sandwich of two cross-grained constructional veneers interspersed with three paper glue sheets, with a base sheet of Mylar to adhere to the substrate and the final leaf of fine veneer on top. This is pressed and bonded for 4 minutes at 135°C before being hand-sanded using belt-driven mops, a process called soft form sanding. A ‘fladder mop’ - fingers of fine grain abrasive in a revolving mop - almost caresses the surface of the veneered panel, enabling the Bentley craftsperson to see that even the contours and apertures for dials and switches are correctly sanded before PU lacquering.
But first the veneered panels are carefully inspected by woodshop craftsmen, who use a ‘wet mop’ to bring out the veneer colour. This highlights any area of minor discolouration, so that the panel can be touched in by hand before the colour is sealed in by PU lacquer in sealed, dust-free spray chambers. The lacquering of the veneered panels is one of the few areas of Crewe where robotics are used. Bar-coded carriers identify the panels, so that the robotised spray arm can read the code by laser, ‘recognise’ the component and follow its shape precisely. A 50,000 gallon water backdrop catches all overspray and separates it out so efficiently that it needs only two top-ups a year: for the most part the water is recycled to be used over and over again.
A minimum of 72 hours is required to cure the lacquered panels before the final flatting, after which the panel is machined around the edge to achieve the final exact panel size. Even here Crewe’s attention to detail ensures that the panel edge of aluminium and its veneered surface is edge-painted to match the chosen veneer, so that no telltale flash of aluminium can ever be seen around the edge once the fascia or console is in place within the finished cockpit.
All told, a full set of 15 separate veneered panels for each Continental GT takes between 16 ½ and 18 ½ man-hours to create, considerably shorter than the 58 hours required to create a Bentley wood set for the previous generation of Crewe-built cars.
However, wood is a natural material and cannot be hurried: including the time taken to stabilise the humidity of the veneer sheets, and the 72 hours for curing after lacquer spraying, the total time required to make a set of panels for the Continental GT comes to 10-12 days, making the wood set the sub-assembly with the longest lead time in the entire factory.
Upholstery and trim traditional - Bentley skills and human judgement oversee laser-accurate execution
Much of the character of a Bentley comes from the ambience of the interior. A keynote of this is the tactile and olfactory delight of hand-stitched full leather trim covering every surface, made using the finest grade leather. But even on the best quality hides there are tiny flaws and minor imperfections, and the judgement of the men and women in the Crewe upholstery shop is critical to ensure that each matched set of hide is as consistent and smooth as possible.
Previously at Crewe, the individual panels were cut out of the complete hide using a press and cutting forms, which were positioned by hand to make best use of the material. In contrast, for the Continental GT the hides are cut using a computer-guided laser cutter. However, human judgement is still critical to the process; craftsmen and women use fluorescent tape to mark the areas of the hide that contain flaws or graining imperfections, and the laser cutter automatically computes the optimum use of the hide to cut out the differently-shaped and dimensioned panels whilst avoiding the marked areas.
The result is that whereas the previous system required up to 15 hides to create a set of hide trim and upholstery for just one car, the new technology enables the same quality to be achieved for just 11 hides per Continental GT.
Complete upholstery sets are still made the traditional way using sewing machines, and some of the most intricate parts of the hide trim are still created by hand. A Bentley steering wheel’s immaculate hide cover, for example, is double-stitched by hand using two needles simultaneously, and the craftsmen and women who perform this task have their own specially designed stations for this exacting and detailed work.
The Continental GT reaches completion
Back on the production line, the sub-assemblies such as seats, fascias, trim and doors are all prepared in areas alongside the production line, another aspect of the re-designed factory that helps to ensure that lines of communication are kept short and effective. Throughout the assembly hall, overhead illuminated displays provide line managers with an instant readout of any areas of concern. Each Crewe associate working on the assembly line can stop its progress by a pull cord next to his or her station; this will automatically show on the display to identify the exact point of hold-up. But the reporting system is also programmed into the power tools themselves. In the unlikely event, for instance, that a bolt has a piece of swarf in its thread, the DC electric power tool will be unable to tighten the fixing to the correct torque setting, and this information will automatically stop the line, ensuring that the Bentley in question proceeds no further until every fixing is perfectly tightened.
In addition to built in process controls, production have established an ethos in the workplace that promotes “right first time” and a way of working where each associate will carry out “buddy” checks to ensure each and everybody in the team are working together to achieve this target.
Close by the production line is the quality area, where there is a Continental GT bodyshell, machined out of solid aluminium to the master dimensions of the car. This ‘full-size functional checking fixture’, known as CUBE, means that any fitting or compatibility issues with components or sub-assemblies can be taken straight to the master and the cause swiftly identified.
The finishing touches
As the Continental GT proceeds towards the end of the assembly line, it passes into a rheostatically controlled lighting booth where bodywork and finish can be examined under perfect lighting conditions. From here it is driven onto the hydropulse shake rig - simulating a brisk drive over uneven road surfaces - which give the suspension the opportunity to ’settle’ to their normal ride height.
Once the drivetrain and suspension has reached its normal road-going state the Continental GT passes to the next station where castor and camber are checked and set using laser guided technology. Only then can the headlight alignment be set once it is certain that all aspects of the chassis and ride height are to their correct specifications.
From here the Continental GT passes into a rolling road cabin where it is run at varying speeds for a minimum of 12 minutes in order to check all functions and measure acoustic performance. The finished car is then driven down the test track to check for rattles and squeaks before passing to the ‘monsoon test’ - an intense shower test lasting a full 17 minutes - to ensure than not a drop of water makes its way into the cabin. Every Continental GT is checked, and every Continental GT is drive tested on the road, before it is considered to have passed Checkpoint 8: the final point in the production process, after which it is passed over to become the responsibility of the Sales division, en route to one of the 140 Bentley Dealers throughout the world.
Site logistics - Traffic flow of key importance and deliveries
The commitment to Continental GT and its increased production volumes requires a lean manufacturing ‘Just In Time’ supply system. As a result, traffic flow is of key importance, and by clearing unused parts of the site around 15% more space has been won so that deliveries can be smoothly processed via two receiving areas under large new weatherproof canopies.
Crewe will keep on site up to three days’ supply of bodyshells, which arrive already painted from the Volkswagen Group’s production facility at Sachsen in Mosel, Germany. The shells are stored on automated storage racking, so that the correct shell and body finish can be called off for its journey down the assembly lines in due order.
Just one day’s supply - two shifts’-worth - of other components will be stored at Crewe. Thus the smooth flow of components onto the production line as they are used - the KANBAN system - is a key element of the new Continental GT production line, and a fleet of tow trolleys will circulate throughout the assembly lines, constantly replenishing component bins.
Transit packaging of components and sub-assemblies poses its own set of challenges. Removing and compacting large amounts of packaging can take up time, cost and space, whilst its disposal creates environmental impact. The solution for Bentley Motors has been to invest in heavy-duty re-usable crates and packaging, and provide them to each of its suppliers, so that as each truck arrives with a fresh delivery of components, it is first unloaded and then refilled with the previous day’s empty cartons, ready for re-use.
Attention to detail - a Bentley priority
One of the first things the visitor will notice upon entering the assembly areas is the cleanliness of the factory, an obsession that extends down to the smallest detail. Rubbish sacks are made of clear plastic, so that team leaders and managers can see at a glance that the correct waste has been put into the proper place. Cupboards are glass-fronted so that their contents are visible - the philosophy is not to have any unnecessary clutter anywhere in the workshops. Around £750,000 (Eu 1.1m) has been spent on the floor finish alone. It is a metallised acrylic coating, originally designed for hospital and laboratory use, which can be buffed spotlessly clean at the end of every double-shift. By every workstation there is a ’shadow board’ with stencilled spaces for dustpan and brush, and each workgroup is responsible for sweeping up any litter or debris in its area.
Even the tool chests, component bins, cupboards and workstations are mounted on large rubber-tyred castors, so that the entire line can be cleared for cleaning once a day.
Bentley Motors’ greatest asset - its people
In planning the new Continental GT production facilities, the directors of Bentley Motors were adamant that they did not want to change the special character and individuality of a Bentley, which strongly derives from the people who design, engineer and build it. Despite the considerable increase in production volumes, automation throughout the Continental GT line at Crewe is only ever used as a means of achieving higher levels of quality, rather than a way of ‘de-skilling’ the human input. Thus there are only two areas of the Continental GT line where robotised machinery substitutes for human being: the lacquer spraying of the veneered wood sets, where both consistency of spray path and health and safety issues make the machine an intelligent alternative; and the robotised application of glazing adhesive in a continuous bead around the window and windscreen apertures of the bodyshell, a monotonous task requiring utter consistency of bead size and nozzle path. Other than these two areas, every assembly operation is guided and controlled by the skilled men and women of the Bentley Crewe factory.
In stark contrast to the Crewe of yesteryear, each working area has a rest area close by the line, where associates can take their tea and lunch breaks and relax. Each area has comfortable seating, a fridge and a microwave oven, so that associates do not have far to walk when the break bell sounds.
Crewe has added to its production staff in preparation for the launch of Continental GT, and those directly employed in production now number 1200. Before any new recruit can work on a Bentley, he or she will spend five weeks in a combination of classroom and practical training. Being Bentley, and committed to unique standards and working methods, the production team elected to create their own specific training programmes staffed entirely from within Crewe, rather than buying an ‘off the shelf’ training solution.
Once within the factory, new associates are allocated to work groups, each with its own team leader. The ratio of team leaders to associates throughout Crewe is 1:6, and the team leader for each area is qualified to perform every task within that group. Daily briefings before each shift flag up any areas of concern, that in turn are reported upwards if the team leader is unable to resolve them. This way, not only are any potential bottlenecks identified swiftly, but every associate is empowered to make suggestions that will improve either quality, productivity or both, as well as being able to develop their own preferred work patterns. Every associate is also recorded on video performing their work, so that the team can study them to find areas of improvement.
A new Crewe - a new generation of hand-crafted Bentleys
In comparison with the highly bespoke Bentley Arnage R and Arnage T, which typically require around 500 man-hours to create, each Continental GT to leave the site at Crewe will have taken some 250 man-hours to build. But it is worth putting these figures in context: for example, a typical high-volume family saloon or hatchback will require somewhere between 20 and 30 man-hours to assemble from start to finish.
The Continental GT is therefore a highly individual and hand-crafted car, whose performance, quality of materials and design represent exceptional value at its pricing level. More importantly, the very factors that make owning a Bentley such a unique experience - the sense that one is driving a hand-made performance machine, made to one’s own preferences and specification - are both retained and safeguarded by the investment, both human and financial, that has been made in Crewe.
To visit Crewe and to see a Bentley being crafted is one of the wonders of the automotive world. In creating the Continental GT production facility, Bentley Motors has ensured that this pleasure will be experienced by a new generation of Bentley drivers, enjoying the sense of personal involvement and commitment that only Crewe and its craftspeople can generate.
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