The first North American Ford to get torque vectoring control will be the 2012 Focus. Ford is pitching the system as a safety- and performance-enhancing addition that helps the car "carve through turns like a downhill skier." We're not convinced.
First, we should understand how the system works. According to Ford, the torque-vectoring (TV) system works by applying "slight braking force" to the drive wheel most likely to slip during throttle application. In our experience, that's typically the inside wheel when exiting an aggressive turn. Ford claims the system's action is "imperceptible" to the driver, simply improving handling.
In reality, the TV system is an alternative to a limited-slip differential, leveraging existing wheel speed sensors and electronic brake control borrowed from the stability control system. How does the TV system mimic the presence of a limited-slip diff? By controlling the amount of wheelspin across the open differential through brake application, preventing the "one wheel peel" open diffs are known for.
The end result? "[A] Focus class-exclusive feature that serves as a confidence-builder for novice drivers, while pleasing enthusiasts with added control when cornering," says Ford.
All well and good so far, right? Not really. In our experience, TV systems' interferences with driver inputs are not only not imperceptible, they're downright annoying. In practice, TV systems aren't predictable in their engagement, often over-limit wheel spin, and generally serve to slow the car and make it harder to drive at the limit--especially when compared to the system they're replacing: limited-slip differentials. Even BMW doesn't get this right, so we don't expect anything special here.
Limited-slip diffs have their downsides, too, particularly in front-wheel drive cars. The first-generation Mazdaspeed3 is an excellent illustration: torque steer galore. But unlike computer-driven electronic nannies, the action of a limited-slip diff is mechanical, and therefore predictable. Don't hammer the gas until the wheel is straight, and expect some tug if you do--particularly over bumpier asphalt. Plan for it. Use it.
You can't do that with torque vectoring. You can't plan for that dab of brake on the inside wheel, which, depending on the surface, can actually reduce front-axle traction even further, particularly if you're already at the lateral limit, leading to understeer where an open diff wouldn't. Further, it taxes the brake system harder, applying the already-overworked front brakes during acceleration as well as braking, leading to reduced times before brake fade begins.
2012 Ford Focus ST
As a cost-effective safety device to help keep non-enthusiasts and other less-skilled drivers safe in tricky weather conditions, we completely understand the TV solution. As a performance enhancer? We're not buying it.
Catch the official announcement on page two.
Ford Technology Allows New Ford Focus to Carve Through Turns Like a Downhill Skier
- The all-new 2012 Ford Focus features standard torque vectoring control to increase vehicle stability in turns by applying slight braking force to one side
- Torque vectoring control is a Focus class-exclusive feature that serves as a confidence-builder for novice drivers, while pleasing enthusiasts with added control when cornering
- Torque vectoring control provides stabilizing braking force to an individual drive wheel in a similar way that a skier or board-rider would shift weight to carving edge when turning
The all-new 2012 Ford Focus is the first beneficiary of a new class-exclusive Ford technology that employs downhill skiing and snowboarding moves to increase vehicle stability in turns.
Engineered to increase novice driver confidence by adding a finer sense of control in curves, the next-generation Focus will please enthusiast drivers as well with the addition of a vehicle stability control system previously reserved for premium sports cars.
"The new Focus is the first North American Ford vehicle to offer torque vectoring control," said Rick Bolt, program manager for the Ford Focus. "This is a technology that has been offered on high-end sports cars, yet Ford is making it standard on their new small car."
Just as a downhill skier or board rider shifts weight to their outside edge in transition from schuss to edge – adding balance and stability to carve through a turn – torque vectoring control provides slight braking force to the wheel and the tire that is subject to potential slippage to help the driver and vehicle gracefully negotiate the curve.
The slight braking pressure applied to just one driven wheel is imperceptible to the driver. The behind-the-wheel experience is an improved sense of stability and control throughout the curve. This increased vehicle stability in cornering situations is sure to please enthusiast drivers yet serves as a confidence builder for novice drivers as well.
Torque vectoring control uses the Focus braking system to imitate the effect of limited-slip differential, constantly balancing the distribution of engine output between the driven front wheels to suit driving conditions and road surface. When accelerating through a tight corner, the system applies an imperceptible degree of braking to the inside front wheel, so that more engine torque goes to the outside wheel, providing additional traction, better grip and improved vehicle handling.
The system is designed to delight experienced and enthusiastic drivers but also to provide less- experienced drivers with confidence and a better sense of vehicle control, especially in difficult driving conditions.
"Torque vectoring control elevates the dynamic capability of the entire Focus model range, from an S series sedan through a Titanium Sport Package hatchback," said Bolt, an automotive enthusiast, frequent road course track-day participant, instructor, former Sports Car Club of America racer and – not surprisingly – downhill skier.
"Because torque vectoring control is on all our Focus models, it will elevate skill sets across a broad range of drivers," Bolt said. "The new Focus is differentiated from other vehicles in the segment by style and design, the technology it contains and the superior driving experience it provides."
The all-new 2012 Ford Focus goes on sale in early 2011.