2007 Bentley Arnage T

Bentley Motors continues the intensive development of its flagship Arnage range with the introduction of a major programme of powertrain and chassis enhancements for the 2007 Model Year. The Arnage's renowned 6.75-litre V8 engine now develops up to 500bhp and is mated to a six-speed automatic transmission benefiting performance, driving dynamics and refinement. The powertrain changes are complemented by subtle exterior, interior and under-bonnet design cues.

Key to this performance increase is the most powerful version of Bentley's legendary V8 engine ever built at the company's headquarters in Crewe, England. In the performance-oriented Arnage T model, the revised twin-turbocharged V8 engine produces a staggering 500bhp and 1000Nm of torque – an 11percent increase in power and a 14 percent increase in torque over the outgoing model. Twinned with the latest six-speed ZF automatic transmission, which uses state-of-the-art computer management, performance and refinement are optimised at all speeds. In the Arnage R and RL models the new engine is boosted from 400 to 450bhp, while torque climbs from 835 to 875Nm.

'The 2007 Model Year Arnage range is clear evidence of our intent to ensure Bentley's flagship model remains at the forefront of technology and delivers the performance, refinement and luxury that every Bentley customer demands,' explains Stuart McCullough, Member of the Board, Sales and Marketing.

The 500bhp Arnage T is a true driver's car with much higher performance and delivers an even more rewarding driving experience. The improvements to the refinement and comfort of the 450bhp Arnage R are equally striking, while the long-wheelbase RL shares the same increased power output together with major improvements to the rear passenger cabin.

'Two years ago we introduced major upgrades to the Arnage's chassis, steering and brakes,' says Dr Ulrich Eichhorn, Member of the Board, Engineering. 'Those improvements meant the car could easily handle a significant increase in power and torque, so work began on this important powertrain programme.'

The 2007 Model Year Arnage also benefits from safety, interior and design improvements. Every Arnage now has a Tyre Pressure Monitoring System, rSAP Bluetooth integrated telephone system and improved driver ergonomics as standard. Additionally, new wheel, exterior paint colour and interior trim options are available, as well as an optional retractable ‘Flying B' bonnet mascot.

The new 2007 Model Year Bentley Arnage range will go on sale from September 2006.

Overview

Uprated 6.75-litre twin-turbocharged V8 engine in Arnage T produces 500bhp and 1000Nm torque, thanks to new low inertia turbochargers and roller tappet system.

Arnage R and RL models uprated to 450bhp and 875Nm of torque.

Latest six-speed ZF automatic transmission with sophisticated locking torque converter provides fast yet ultra-smooth gearshifts.

New Electronic Stability Programme (ESP) logic system improves dynamic response and handling with less intrusive intervention when a reduction in grip is detected.

New Tyre Pressure Monitoring System fitted as standard to all Arnage models.

Improved driver ergonomics thanks to 25mm increase in length of steering column and in vertical steering wheel adjustment.

Exterior design styling changes includes new dark finish to Arnage T front radiator and bumper grilles, standardised bright chrome finish to R and RL grilles, and Bentley ‘B' badges on the D-pillars.

Underbonnet styling now features a black crackle finish to the Arnage T's inlet manifold, embossed Bentley logo on plenum chambers and new ‘6¾ LITRE TWIN TURBO' engine plaques.

Interior design updates include new hide-trimmed gearlever and chrome gearlever bezel providing access to semi-automatic transmission function.

New Thin Film Technology driver information panel displays more comprehensive and clearly accessible information.

Arnage RL model receives additional standard specification including rear centre armrest bottle cooler, veneered rear centre cushion box, rear rSAP master telephone system, and reversing camera (US, EU, Australia and New Zealand markets only).

Engine

Bentley's 6.75-litre V8 engine is the centrepiece of the 2007 Model Year Arnage development programme. This remarkable engine, the fundamental design of which has served Bentley models proudly for nearly five decades, has been extensively re-engineered to provide, in Arnage T specification, 500bhp and 1000Nm of torque - figures that ensure that the legendary Bentley wave of torque is even more astonishing than before. Top speed of the Arnage T has risen from 168mph/270km/h to 179mph/288km/h, while the 450bhp Arnage R and RL's maximum speed increases by 13mph/21km/h to 168mph/270km/h.

When the first V8 engine was built in the1950s, the design brief unwittingly benefited later generations of Bentley engineers. It was a very forward thinking design with an all-aluminium construction, a five main-bearing crankshaft, and a well-supported camshaft. The steps taken then laid the foundations for the longevity of the engine.

'People might raise an eyebrow when they are told that the V8 engine in their 2007 Model Year Arnage was first used by Bentley in 1959,' says Bentley Motors' Director, Powertrain and Chassis, Brian Gush. 'But the reality is the basic design was so good that we have been able to continually improve it for nearly 50 years.

'One of the reasons the engine has evolved so successfully is the position of the exhaust valves, high in the cylinder head, originally designed for rapid heat dissipation to help engine cooling. Decades later it meant that we could heat the catalytic converter due to the short path from valves to catalysts, which benefits exhaust emissions. This is just one of the reasons why this brilliant engine lives on today.'

That first 6.25-litre engine produced around 200 horsepower – the new 2007 Model Year 6.75-litre V8 has more than twice that output, with 500bhp and 1000Nm of torque for the Arnage T. It was the introduction of turbocharging and intercooling in the early 1980s that saw step-change increases in the V8's performance, and the latest engine programme is no different. Two new low-inertia turbochargers operate with far greater efficiency at lower engine speeds – they reach maximum turbine speed in half the time of the previous unit – thereby ensuring significantly reduced turbo lag and that prodigious wave of torque at any revs.

Furthermore, a reprofiled camshaft with an all-new roller tappet system provides revised valve timing and substantially improved refinement. These changes also deliver for increased power, enhanced durability and ensure compliance with European EU IV and US LEV II standards. Although the 2007MY 6.75-litre engine produces around 300 horsepower more than its 1959 predecessor, its fuel consumption is only 60 percent of the original and thanks to its advanced fuel injection and exhaust controls, its emissions output is an incredible 99 percent lower than Bentley's first V8.

Drivetrain & Chassis

Such an impressive increase in power and torque is, however, of little benefit unless the powertrain is capable of delivering it to the driven wheels. For this reason Bentley's engineering team opted to introduce the latest six-speed ZF automatic transmission to the Arnage range. This state-of-the-art system offers two further ratios than the previous gearbox and has several key advantages over its predecessor:

The wider range of ratios is specifically tuned to each Arnage model, ensuring greater flexibility, response and refinement for every model.

Performance feel is also improved by using a sophisticated locking torque converter system which provides a more rapid response to throttle inputs.

Three transmission modes (Drive, Sport and Semi-Automatic) allow the driver to take full advantage of the new gearbox. Semi-Automatic mode is accessed by placing the gearlever into the sequential manual gear-selector gate, where a new ratio can be engaged simply by pushing the lever forwards or backwards.

A sophisticated electronic management system plays a major role in providing fast yet smooth gearshifts regardless of how the car is being driven. Previously the Arnage's engine and transmission were governed by independent electronic systems; in the 2007 Model Year, an uprated Bosch computer-controlled management system ensures that both parts work as a single unit to produce a supremely refined yet highly responsive drivetrain.

'The new ZF gearbox gives us a different dimension in transmission control,' says Dr Ulrich Eichhorn, Member of the Board, Engineering. 'Our main objective was to get the engine and transmission working together enabling us to transmit every ounce of power. Using the lock-up in all gears eliminates what we call the ‘rubber-band' effect – the surge of engine speed without a corresponding acceleration of the car – and gives much more immediate connection of throttle input to road speed.

'As the engine speed approaches the point at which a gearshift is due, it signals to the transmission that it is time to shift, so the ratio changes are much quicker - it feels significantly faster from the driver's seat. Similarly, when the gearbox is ready to change up it asks the engine to reduce the torque just for the period of the shift, which adds to the refinement.'

Another important development for the 2007 Model Year Arnage range is the separation of the sports suspension and sports gearbox settings, allowing the driver to select their preference for each system independently – via a ‘Sport' button on the dashboard for the suspension and by positioning the gearlever for the transmission's Sport mode.

A comprehensive chassis tuning programme was instigated alongside the powertrain updates to ensure the Arnage's chassis comfortably handles the additional performance. Refinements to the ESP logic system allow more spirited handling without any reduction in stability or safety.

The Traction Control system is extensively recalibrated with the aim of avoiding unnecessary reduction in engine torque. The ESP system now monitors the car's overall stability rather than simply loss of grip to the wheels. This reduces the amount of intervention required and restores power earlier and more progressively, allowing the power of the engine to be fully exploited.

'We don't believe in creating power and then taking it away,' says Brian Gush, Director, Powertrain and Chassis. 'This new system allows the driver a lot more freedom to feel where the traction limit is without ever getting into trouble. The traction control is much more progressive and proportional – you can drift the car with some wheelspin but it never lets you get in any trouble. It is a calibration which keeps the spirited driver in mind.'

Design

Following the detailed design updates made to the 2005 Model Year Arnage, the latest models receive further exterior styling changes.

‘The revisions we made to the Arnage series two years ago gave the range exactly the sort of contemporary yet authentic Bentley feel that it needed,' says Head of Exterior Design, Raul Pires. 'Now with big increases in power and performance we wanted to add some subtle design cues to reflect the differences between the Arnage models.'

The performance intent of the Arnage T is underlined by the addition of a new dark finish to its front radiator and bumper grilles. A standardised bright chrome finish is applied to the R and RL grilles while Bentley ‘B' badges have been applied to the D-pillars on all models.

To highlight the superb feat of engineering beneath the Arnage's bonnet, a newly styled engine bay leaves no doubt as to the potency of the car. A black crackle finish has been applied to the Arnage T's inlet manifold, while every model displays an embossed Bentley logo on the turbocharger plenum chambers and new ‘6¾ LITRE TWIN TURBO' engine plaques.

Additional optional extras include a 19-inch six-spoke disc wheel for the R and RL models, and 19-inch five-spoke ‘Blade' sports wheel for the Arnage T. Also available across the range is the famous winged ‘B' mascot, which saw a welcome return this year on the Diamond Series Arnage. The iconic mascot – which can retract neatly into the grille surround – was originally designed by motoring artist F. Gordon Crosby and first used on the 1930 Bentley 8 Litre.

Interior design updates include a new hide-trimmed gearlever, chrome gearlever bezel, and new Thin Film Technology driver information panel to display more comprehensive and clearly accessible information. The Arnage RL model receives additional standard specification including a rear centre armrest bottle cooler, veneered rear centre cushion box, rear rSAP Bluetooth master telephone system and reversing camera (US, EU, Australia and New Zealand markets only).

Conclusion

The significant upgrades to both engine and transmission mean every new Arnage will not just match customer expectations but surpass them on all fronts, as Dr Franz-Josef Paefgen, Bentley Motors' Chairman and Chief Executive explains:

'These important powertrain enhancements reaffirm the very essence of the Bentley Arnage, offering our customers an absolutely unique blend of seamless power and torque which produces storming performance when you demand it and blissfully relaxed cruising when you don't.'

by Bentley

The luxurious Bentley Arnage was debuted at the Sarthe Circuit in France on the 26th of April of 1998. This was considered fitting because this was the racecourse where Bentley's had finished first place in the legendary '24 Hours of Le Mans' at least five times during their history. The name Arnage was taken from the challenging bend at the famous track. The Arnage measuring 197 inches long, 75 inches wide, and featured a curb weight of more than 2.5 metric tons. At one point, it was the fastest and most powerful four-door saloon on the market.

The first of a new generation of sporting Bentleys, the Arnage featured great mid-range pulling power alongside superb levels of refinement. A large luxury vehicle produced by Bentley Motors in Crewe England, the Arnage was introduced in 98 and ran until 2009. Introduced in the spring of 1998 alongside it's Rolls-Royce branded sibling; the Silver Seraph, both were the first brand new designs for the two marques since 1980. Completely breaking from tradition, these new vehicles had bodies constructed at the Crewe factory, with its internal combustion engines built elsewhere.

Some Bentley enthusiasts were unhappy that the vehicle lost the traditional 6750cc V8; a powerplant that could trace its history back to the 1950's, it instead featured a 4.4-liter turbocharged V8 engine from BMW. The BMW engine, with Cosworth-engineered twin-turbo installation, was an excellent unit that delivered tons of power and torque. Diehard Bentley devotees weren't pacified through until September of 1999 when the Volkswagen Group, Bentley's parent company, offered the huge Rolls-Royce 6.8-liter V8 in a new version of the Arnage.

In 1998 during the takeover battle between BMW and Volkswagen Group for possession of Rolls Royce and Bentley Motors, BMW threatened to halt the supply of their engines if Volkswagen Group won. This threat was later withdrawn when BMW acquired the right to manufacture the Rolls Royce marque at a new location and it was obvious that Volkswagen couldn't accept the risks associated with having their long-term business partner as a rival. In response, Volkswagen got ready their old 6.75 liter 16-valve engine from the Turbo R, which they mated to an outdated 4-speed automatic. Unfortunately, this combination made for a thirsty engine that wouldn't meet Government-imposed emission standards without quick modifications.

The BMW-powered version was called the Green Label, while the Rolls-Royce engine model was dubbed the Red Label. Both Red and Green Label vehicles received stiffer body shells along with larger wheels and brakes. 2000 model year vehicles were fitted with more powerful brakes while the Green Label model received the 18-inch wheels that were displayed by the more powerful Red Label variant. Because of the extra weight of the British engine, the stiffer body shell was a priority, the same with the larger brakes. Unfortunately though despite the larger brakes, the performance only worsened with the additional weight of 6.75 engine. The 1999 Green Label had a braking performance from 70-0 at 172 feet while the Arnage T's performance was 182 feet from 70-0.

Other revisions included adding park distance control to the front and rear, making a pop up Alpine navigation system standard, and increasing the rear-seat legroom. The steering rack was also modified to reduce steering effort at low speed and adding power-folding exterior mirrors. The headlight lens covers transitioned from glass to plastic.

Bentley's public relations department hinted at customer demand for the reason behind the reversal of the previous two-valve per cylinder 6.75-liter unit for the Red Label. Most consumers accepted this, but few criticized the BMW motor as lacking in power and dull. The BMW-powered Arnage was more up-to-date, more fuel-efficient and featured 32 valves with double overhead camshafts, twin-turbo and Bosch engine management technology, rather than 16 valves, single turbo, and a pushrod motor with considerably less advanced engine management.

Less than a second of the 0-60 mph time was shaved from the Red Label's growth in motive power. The BMW's twin-turbo unit did continue to remain more responsive and nimble from the driver's perspective due to its DOHC engine being more responsive along with better weight balance and nearly 600lb lower curb weight.

The Green Label was sturdier and more reliable as well as being cheaper to service in the long run. The BMW engine's output drawback was the ZF 5HP30 transmission; which wasn't rated to handle more than 413 lb/ft of torque that the twin-turbo engine was tuned to produce.

The production of the aged 6.75 liter Roll's Royce engine was outsourced for use in the continued Azure and Continental models to Cosworth, so going back to the old standby engine was an easy choice for the company. The Red Label model went back to the old V8 engine that featured torque of 835-newton meters with a single Garrett T4 turbocharger. At this time, it was the highest amount of torque for a four-door vehicle. The GM-sourced four-speed 4L80-E automatic transmission also made a reappearance.

The Green Label was very quietly dropped shortly afterward in 2000.

The Arnage RL was a long-wheelbase model introduced in 2001. It was 9.8 inches longer than the original Arnage with the extra length at the rear doors and its C-pillar. The RL model had rear-wheel butts a few inches further back than the standard Arnage model whose wells butt up against the rear door-frames. The effect was a larger rear area on the interior of the vehicle. Sometimes dubbed 'double-cut' in the U.S., the type of saloon stretch was named this was because of the two main points where the car is extended. Each Arnage RL was individually customized for the buyer.

Arnage RL wheelbases ranged from 131.3 inches to 140.4 inches, and even sometimes 151.3 inches. The longest wheelbase version, the 151-inch version had its length stretched between the front and rear doors instead of at the C-pillar at the rear doors, American limousine-style. The large car handled well due to the suspension being returned for the added weight. Many Arnage RL limousines were ordered with bulletproof elements, reflecting the clientele of the vehicle. For a hefty price tag starting at $243,000, a full B6 package was available which offers protection from grenades and assault weapons. As of 2006, the Arnage RL continues to remain in production.

The RL featured a completely reworked version of the old 6.75-liter V8 engine. Over half of the engine's parts were brand new, with the old Zytech system being replaced with Bosch Motronic ME7.1.1 engine management and two small Garrett T3 turbochargers replacing the single large T4. This new engine was said to be capable of meeting all future emissions requirements and developed 405 metric horsepower and 835-newton meters. Similar to the originally Cosworth-BMW unit developed for the 98 Arnage, the RL was powered by a modern twin-turbo unit with a state-of-the-art electronic management system.

In 2002 Bentley updated the Red Label as the series two Arnage R. The Arnage T was the more sporting model and was introduced in contrast to the Arnage R. Same with the RL the Arnage R features two Garrett T3 turbochargers. It also claimed to be the most powerful road warrior at its debut at the Detroit Motor Show in 2002. There were twin-turbochargers, like with the Arnage R, but they were tuned to develop 465 metric horsepower and 875-newton meters. The T's top speed was 170 mpg and could achieve 0-60mph in just 5.5 seconds. All R & T models share the same 122.7 in wheelbase. In 2005 the Arnage range was updated and the front end now resembled the new Continental GT.

In honor of the Queens Golden Jubilee in 2002, the Bentley State Limousine was an official vehicle created by Bentley Motors Limited. Only two were built. The car's twin-turbocharged 6.75-liter V8 engine was converted from Bentley's Arnage R version to produce 296 kW; 397 bhp and 616 lb/ft or torque.

For 2007 the Arnage R received low-inertia Mitsubishi units designed to enhance engine response that replaced the Garrett turbochargers. This model year's engine was joined to a variant of the six-speed ZF automatic transmission found in the Continental range. The engine capacity was increased from 411.8 cu in to 412.6 cu in. Due to the new tuning, the horsepower was bumped up to 500 (368 kW; 493 bhp) and 1,000-newton meters in the Arnage T, while the Arnage R featured 460 metric horsepower and 875-newton meters. The Arnage T was performance-oriented and could reach 0-60 mph in just 5.2 seconds with a top speed of 179 mph.

For 2006 Bentley commemorated their 60 years of production at the Crewe factory with a unique Diamond Series Arnage. A total of 60 vehicles were planned, mostly for the United States. The vehicles featured diamond-quilted leather seats, diamond wood inlays, special 19-inch alloy wheels, a stainless steel front bumper, and Union Jack badges on the front wings.

Two years later in September of 2008, it was announced that Arnage production would cease the following year, once a final run of 150 'Final Series' models had been completed. The Final Series included the Arnage T powertrain and the twin-turbo 6.75 V8 engine that produced 500 metric horsepower and approximately 1,000-newton meters of torque. Through a six-speed ZF automatic transmission, the powertrain delivers torque to the rear wheels.

On the exterior, the Final Series featured special 20-inch alloy wheels, body-colored headlamp bezels, a retractable 'Flying B' mascot, dark tint matrix upper and lower grilles, lower front wing vents, special badging, and a 'Jewel-style' fuel filler cap. Mulliner designed the interior of the car and featured Final Series kick plates, special chrome trim, drilled alloy pedals, two picnic tables and a rear cocktail cabinet. This model also came with a premium 1,000-watt audio system by Naim Audio and came with four distinct umbrellas.

Forty-Two exterior color schemes were offered with this model, twenty-five interior hides, and three wood veneers. Customers could also specify bespoke color- matching offered by Bentley. The Arnage Final Series marks the 50th Anniversary of Bentley's V8 engine. The 2009 version of the engine continues to be loosely based on the same design that was introduced way back in the 1959 Bentley S2. Though the 2008 engine shares no identical parts with the 1950 model, the final common item having been replaced in 2005. Advertising of the engine when first introduced described the power and torque as 'adequate'. Twin-turbocharged, the all-aluminum alloy engine delivers 0-60mph in just 5.3 seconds. The car weighs 2.5 tons.

In 2009 a replacement model called the Bentley Mulsanne was debuted in August at the Pebble Beach Concours d'Elegance in Monterey, California. Because of separate parent companies, the design of the Mulsanne will now be completely separate and independent from Rolls-Royce cars. Rolls-Royce is held by BMW and Bentley is held by the Volkswagen Group.

Sources:

http://en.wikipedia.org/wiki/Bentley_Arnage

http://www.compucars.co.uk/car-reviews/bentley/review/?arnage

by Jessican Donaldson