Posted Jun 27th 2012 11:57AM
At this year's North American International Auto Show, Bentley unveiled something quite incredible - a V8 version of its Continental GT sports coupe that is an estimated 40 per cent more fuel efficient than its 12-cylinder brethren.
With the ever-increasing emphasis on the environment, tailpipe emissions and fuel reserves, it's no wonder that alternative-fuel vehicles are seen as the answer to a solution that is very much needed in the foreseeable future. However, it's also worth noting that there are some pretty sharp minds out there working on optimizing the performance of the good ol' internal combustion engine - and the 2013 Bentley Continental GT V8 provides ample proof of this fact.
The entire Continental line, starting with the original GT coupe introduced in 2003, has only been offered with one type of engine: the twin-turbocharged W12. Over the years, this engine has been modified and tweaked to produce more power, more torque and more performance.
Click here to see how the V8 stacks up in our review.
Related Gallery2013 Bentley Continental GT V8
Now we have the new GT V8 with a twin-turbocharged V8 engine in place of the 6.0-litre W12. While it may seem an affront that an exclusive car such as Bentley should be fitted with a mere eight cylinders, it's worth remembering that the latest Mulsanne, the biggest car in the company fleet, also employs a twin-turbo V8.
But there's yet another opportunity for dissenting opinion: The Mulsanne has its own bespoke 6.75-litre V8, but the new Continental features a smaller 4.0-litre unit that was developed in partnership with Audi, which uses a variation of this same engine for the new S8 super-sedan.
Still, nothing speaks louder than outright performance. The twin-turbo V8 (500 horsepower; 487 lb-ft of torque) is almost a match for the twin-turbo W12 in standard spec (589 hp; 516 lb-ft). Sure, the V8 is a slightly more relaxed engine from a standing start - 4.8 seconds for the sprint to 100 km/h versus 4.6 seconds for the W12 - and the car's top speed is a "measly" 303 km/h (318 for the W12) - but in the grand scheme of things, this difference is negligible.
It's even more negligible when you consider that 40 percent improvement in fuel efficiency compared to the W12. This slick bit of engineering has been achieved through a number of means.
First, just by downsizing from 12 cylinders to eight and the corresponding weight reduction in the engine bay, the car is 16 percent more efficient. The V8 also features cylinder deactivation technology, as first used by Bentley on the Mulsanne, which allows it to run on just 4 cylinders when not under significant load. This represents a 5 percent gain.
The engine has also been calibrated for optimum efficiency (3 per cent), thermal management of engine heat has been improved (2 per cent), and a variable power steering pump has been brought on board to reduce load on the engine (3 per cent).
The Bentley also benefits from an overall reduction in weight (2.5 per cent), low rolling resistance tires (1 percent), an energy recuperation system that charges the battery under deceleration (1.5 percent) and an 8-speed automatic transmission (6 percent). Total them all up and you get 40 percent - simple, right?
Most of the technological improvements are seamless in nature; the average driver probably wouldn't be able to tell something different is going on under the taut skin of the GT V8. But the final improvement on the list, the 8-speed automatic, while an improvement over the 6-speed automatic found in the W12 in terms of efficiency, certainly falls short of providing a rewarding experience behind the wheel.
For the drive event, track time was arranged at the Circuito de Navarra in northern Spain, followed by a road test through the region's picturesque surroundings. The order of things is important here because I ended up being frustrated by the nuances of the transmission, something that might not have happened if the agenda had been reversed.
On track, even in manual mode, the cogs would switch of their own accord rather than waiting for the driver to take action. A truly sporting vehicle would at least have one drive mode that kept the engine bouncing off the rev limiter until the driver made a move.
The car also a real stickler when it came to downshifting; approaching a corner at speed always took more care than expected because the engine would, for example, refuse to go from third gear to second at 80 km/h, but was happy to respond at 79 km/h.
To make matters worse, there was no indication that a lower gear had not been engaged - no warning beep, as one finds on other cars. So, on a number of occasions, I attempted to put the power down coming out of a slower corner only to discover that I was in too high a gear. The fully automatic mode proved to take some strain off the brain, but the 8-speed was clearly not calibrated to hold maximum revs before shifting.
Of course, close to 100 per cent of the car's drivers will toss it into full automatic mode and let the transmission do all the work - every time. But even some of those drivers would want to know that there's some race-inspired thinking in there somewhere.
But then, as mentioned, out on public roads it was very much a different story. When put under less pressure to be in the proper gear in an instant, the combination of the V8 engine and the 8-speed performed beautifully the entire time, even in manual mode.
Free from the distractions created by the transmission, the on-road experience afforded the chance to appreciate the dynamics of the all-wheel-drive super-coupe with its 40/60 rear-biased torque split and a traction control system that has been recalibrated for less intrusive behavior.
Also worth mentioning: Despite four fewer cylinders, the exhaust note of the GT V8 is downright nasty and it rivals the W12 for sheer, blood-curdling appeal. The thing has three different sounds - one for start-up, another for the mid-range and a third that chimes in at the top end.
All told, despite the disappointing transmission calibration choices, the 2013 Bentley Continental GT V8 is an inspired premium sports coupe and a poster boy for the incremental-improvement movement. The slight hit in performance is easily offset by the gains in efficiency. Not only that, this version of the Continental will be 10-15 per cent less expensive than the W12 in markets around the world. Nice.
News Source: Evergeek