Unleashing Power: The Resurgence of Bentley's Turbocharged Legacy

No fewer than 30 years passed between the introduction of the R-Type Bentley Continental and the subject of this month’s Motor Sport colour test, the Bentley Mulsanne Turbo; more than a generation during which those offerings marketed behind the Bentley radiator were basically Rolls-Royce models bearing cosmetic alterations. That’s not really meant to sound pejorative, for we’re not dealing with run-of-the-mill machinery; but the fact remains that this policy would have delighted those Rolls-Royce directors who presided when it acquired the assets of the Bentley company way back in 1931. Immediately after that takeover, the Rolls-Royce company devoted itself to obliterating Bentley’s own individual character, a process which continued after 1952 with equal effect, if not with the same premeditated ruthlessness that had characterised the 1931-39 period. The Bentley marque may have had its loyal devotees over the past quarter-century, but since the era of the Continental, mechanically they’ve had to rely on variations of the Silver Cloud, Silver Shadow and Silver Spirit theme. Now Bentley individuality is on offer once again with the £61,744 Mulsanne Turbo, the first forced-induction machine to carry the winged ‘B’ motif for half a century.

The Mulsanne Turbo is based on the large, stylish Rolls-Royce Silver Spirit/Bentley Mulsanne model which appeared at the end of 1980. With the advent of this new model, some enthusiasts confessed to being a trifle disappointed: instead of endeavouring to take on Jaguar and Mercedes-Benz in the agility stakes, Rolls-Royce decided to concentrate on what it knew it could do best. The Silver Spirit and Mulsanne are high quality, beautifully-built luxury saloons constructed to an impressively high standard, quiet, refined and relaxing cars in which to cruise at speed, but with a 0-60mph time in the order of 10sec and a top speed of around 116mph, they were hardly likely to electrify the wealthy businessman used to a Mercedes-Benz 500SEC or a Jaguar XJ12. That’s where the Mulsanne Turbo comes onto the scene. Adding a turbocharger to the 6750cc aluminium-alloy V8 engine catapults this two-and-a-half ton luxury saloon into a new performance class. The Bentley Mulsanne Turbo is now a very fast car indeed, although it does take some time to get to grips with its sensitive controls. It was with trepidation that we nosed out onto a rain-soaked M6, viewing the world from the imperious comfort of the Bentley’s leather-trimmed, high-backed seats, and it is only with time that one comes to appreciate that the Mulsanne Turbo keeps its 235/70VR15 Avon tyres well and truly in contact with the road, not withstanding initially disconcerting levels of roll, dive and squat.

Of one thing there is no doubt: this Bentley has no shortage of power. The turbocharger has helped raise the power output from 198 to 298bhp, while throttle lag is kept to a minimum by a valve to recirculate unwanted air pressure back to the intake side to keep the turbine spinning when the throttles are closed, a system similar to that on Ferrari’s Formula 1 V6 turbocharged engines during 1981.

The turbocharged V8 engine is unobtrusive, but certainly not quiet in the manner of Jaguar’s fuel-injected V12-cylinder unit. For sheer performance, however, the Bentley is quite remarkable. On a pretty damp tarmac surface, and with four adults ensconced within its club-like interior, the Mulsanne Turbo reached 60mph from rest in 7.5sec and then surged on to 100mph in a fraction more than 18sec. Not only does the Mulsanne Turbo knock its normally aspirated stablemate into a cocked hat in terms of sheer performance, but it also beats the much-vaunted Jaguar XJ12 from standstill to 130mph – although we could never coax it over 13mpg! Thus a full 23.5-gallon tank would last about 270 miles.

“The interior of the mulsanne turbo is a world apart – an air of uncompromising luxury”

Once the driver has come to terms with the supple suspension, and learnt to have faith in the ultimate adhesion despite its rolling gait, this very large saloon can be hustled along at remarkable speeds, even on twisting country roads.

The power steering is very light, and the large steering wheel endowed with a notably thin rim, but one soon gets into the habit of gripping it delicately and placing the Bentley into corners with considerable confidence. On wet roads, if you keep your foot planted firmly on the throttle, you can induce slight oversteer, even to the point of losing rear grip, but a touch of corrective lock brings the Mulsanne Turbo back into line with all the responsiveness of a taut little sports saloon.

Over deep ripples and bumps on my local lanes the Mulsanne Turbo rode serenely without any problems. On dry roads I found myself covering familiar country over secondary roads no less quickly in the Mulsanne Turbo than in my normal staff car, a Capri 2.8i, which is a great fun car on twisting routes and covers the ground with impressive efficiency. That, for me, says a great deal about the way in which the Bentley Mulsanne Turbo has been developed.

The interior of the Mulsanne Turbo is, quite simply, a world apart. You enter, rather than get into, this impeccably finished environment, and immediately the senses are assailed with the fragrance of quality. Our test car’s exterior was finished in a restrained shade of green, complemented by the light tan Connolly leather upholstery. Beneath one’s feet lie deep pile Wilton carpets, and there are sheepskin rugs on top of these as well. Just to complete the aura of uncompromising luxury, rear seat passengers are provided with individual sloping footrests on which to place their weary hand-crafted shoes!

The seats are quite outstanding. I suppose it is possible to argue that a little more lateral support could be appreciated, but I found them splendid in every way. They offer superb comfort, and the adjustments provided, electrically, by the control on the centre console, enable anybody to find a comfortable position. Rear seat passengers are catered for with individual reading lights and mirrors.

Through the two-spoke steering wheel the driver is faced by a discreetly labelled 140mph speedometer bearing white lettering and needle on a matt black background. To the left of the driver there is a digital read-out panel including a clock, on-board computer readings and the exterior temperature. On the far right of the fascia is the ignition control, below which is fitted a three-position knob to control sidelights and headlights. Steering column controls deal with gear selection for the automatic ’box (right) and indicators (left). The parking brake is foot-operated with a release lever behind the fascia and the lights are dipped by means of a good old traditional foot switch which makes a pleasant change from most cars that come our way these days.

The automatic split-level heating and air conditioning functions with impressive promptness. This was one of the few cars in which it was possible to channel warm air onto one’s feet and cool air onto one’s face without any undue drama or difficulty, while the radio/stereo system was first class, as one would expect.

The large bonnet swings forward to reveal the daunting mechanical package beneath, while the capacious, carpet-lined boot houses the Bentley’s spare wheel beneath the floor and provides a generous tool kit which is fitted on a special tray.

Distinguished visually from its normally aspirated counterpart, the Mulsanne Turbo sports a radiator shell painted to match the rest of the car’s bodywork: from a purely personal point of view I would have preferred the normal, unpainted, radiator, but then these things are all subjective. . . . Right near the end of the car’s spell in our hands a worrying high-speed misfire developed, and this was eventually traced to a faulty sparking plug on the Mulsanne Turbo’s return to Crewe. That was the only mechanical blot on this Bentley’s copybook, an unfortunate minor footnote to an otherwise trouble-free week’s motoring.

As we mentioned earlier, the Mulsanne Turbo’s price is £61,743.50 of which £12,000 is tax, so our Government will doubtless be happy to see as many of these Bentleys sold as possible! Which leads us to the ultimate question —​ is it actually worth the money?

Assessed purely as a motor car against its significantly less expensive rivals, it must be questionable as to whether the Mulsanne Turbo can justify its price tag. However, for the well-heeled connoisseur who has the means to finance this sort of outlay, who prides himself on impeccable taste and appreciates near-flawless standards of finish and refinement, it probably is. There are certainly other luxury cars that deliver comparable performance allied to better overall handling, but there is nothing, in my experience, that delivers these qualities in the same distinguished, haughtily upper-crust, and oh-so-British style as this turbocharged Bentley saloon.

Taken from Motor Sport, May 1983