PALM SPRINGS, CA – The Bentley Bentayga sure looks like an ultra-luxury vehicle, from its regal exterior to its opulent interior. But two innovations that make the brand’s first SUV special are not readily seen.
One is under the hood. It is a big all-new 6.0L W-12 engine with both direct injection and low-pressure injection as well as two twin-scroll turbochargers.
It produces 600 hp and an equally impressive 663 lb.ft. (900 Nm) of torque. Bentley calls it the most advanced 12-cyl. engine in the world. Because of it, no other SUV tops out at 187 mph (301 km/h).
The other technological standout is an electrically actuated suspension system that provides on-road ride sophistication and off-road ruggedness. The system features the first application of the auto industry’s emerging 48V technology, resulting in a suspension that responds more quickly than a conventional hydraulic system setup.
Mercedes-Benz was the first automaker to introduce an electric 12V active suspension system. Bentley is first to market with a 48V version.
Bentley put the ironman engine and classy chassis in the Bentayga to distinguish it as the most powerful SUV in the world and as a vehicle with go-anywhere capability.
Until now, Bentley, known for its elegant exteriors and interiors, has not typically paved the way in advanced technology.
“We’re too small of a company to be a leader there,” says Cameron Paterson, a native of Scotland who oversaw the Bentayga’s vehicle integration as director-whole vehicle engineering.
Bentley is part of the Volkswagen Group. Because of Bentley’s low-sales volume, the British automaker looks to the group’s central engineering for technical assistance rather than going it alone.
“We developed the Bentayga with our group partners,” Paterson says. “That is the only way to make it work.” In a WardsAuto Q&A, he talks about what makes the Bentayga technologically special.
WardsAuto: First talk about the engine and then the 48V suspension system.
Paterson: The W-12 engine is similar in format to the preceding engine, but otherwise it is brand new from the ground up. We designed it to be lighter and more efficient.
It is a very clever engine. It is direct injection but it also has traditional port injection. This allows it to be powerful and yet meet the stringent emission and fuel-economy regulations.
It has twin-scroll turbochargers which allow for very short and transient performance and gets up to maximum torque in 1.1 seconds, which is a third of the time of the previous W-12.
This engine also has variable displacement which, under light loads, shuts down one bank of the engine. It is not always the same bank. It will switch to left and right.
WardsAuto: Why?
Paterson: To even the wear. It is completely seamless. The customer won’t know six of the cylinders aren’t in operation.
WardsAuto: What are the horsepower and torque differences compared with the previous model?
Paterson: The current engine is actually 635 hp, a little more than the new one. But the new one has the capability to do more, to deliver a lot more during its cycle.
Rolf Frech, Bentley's board member-engineering, tells what's special about the new Bentayga's engine and suspension system.
WardsAuto: Describe the active-suspension system and its first 48V application.
Paterson: It is an electronic anti-roll system we call Bentley Dynamic Ride. We went with 48V because it allows more power, more oomph. It much more quickly controls the ride and roll characteristics. It is most noticeable when you are on a winding road. The body roll is minimal. It makes the Bentayga nimble like a sports car. It belies its size.
The vehicle’s main electrical system remains 12V. The 48V system is an island. The componentry is in the rear, below the spare tire. The system consists of a DC/DC converter that takes it from 12 to 48 volts The charge is held in a couple of super capacitors. They can store the charge long enough to operate the system.
WardsAuto: Was there any thought of going with 12V?
Paterson: We did look at that. It’s just not as quick and powerful enough, particularly for a big vehicle like a Bentley. There’s no point in doing half a job. We needed a system that would do the job properly.
WardsAuto: How’s it work exactly?
Paterson: Within the actuators, there are planetary gear sets that adjust depending on sensor input from the wheels, and change the stiffness of the roll bar instantaneously. They are adjusting all the time based on the input they are receiving.
WardsAuto: And this is where 48V comes in?
Paterson: You need a 48V system to give the actuators enough power to operate.
The suspension provides stability during high speeds and on rough surfaces. It also has the added benefit of improving ride comfort on-road and particularly off-road. The ride is quite serene even during dramatic off-road conditions.
We call this the active chassis. We will later launch a conventional passive version. (Also in the works are a V-8 and diesel engine for the Bentayga as well as a plug-in electric hybrid powertrain.)
We always launch top drawer, coming in with a big engine and all the features. It makes things difficult to do it that way, but it is the right thing to do.
Bentley Dynamic Ride is a first for the industry. It is much, much faster (reacting) than a hydraulic system. It adds some weight with the actuators for each roll bar and the super caps and other electronic equipment. But it is 20 kg (44 lbs.) well spent.
WardsAuto: Do you think of yourself as working for the VW Group or for Bentley?
Paterson: I definitely consider myself as part of Bentley, but I never pretend we could do it without the VW Group.
