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These Saabs really get a grip

First all-wheel-drive cars offer sharp performance

STORA HOLMS, Sweden -- The Saab was sideways, front wheels pointed right, as it slid left through a sharp and wet-gravel corner on a test track here. Sideways, but perfectly stable.

Was Erik Carlsson, the great rally driver, at the wheel? No, just me.

I'm capable of sliding a car sideways in a controlled drift through a corner -- after all, I learned to drive on New Hampshire's frozen lakes. But it takes a balance of delicate gas control and tender steering to do so. In this case, I was not doing any work. I put pedal to the metal, counter-steered, and let the car do what it was going to do -- get sideways on its own, but go no farther.

That's significant, especially for New England drivers, because Saab is finally bringing all-wheel-drive to its cars. It seems odd that the company trails other manufacturers in spreading all-wheel-drive throughout its lineup, considering that Saab built a reputation in the United States on the winter capabilities of its front-wheel-drive systems. Back in the day, Saabs were among the best-performing in slush, sleet, and snow.

Now, the company's new 9-3 series introduces the fourth generation of a Haldex four-wheel-drive system. Initially, this so-called XWD system will be exclusive to 9-3 Aero Sport Sedan and SportCombi (wagon) models. In those models, it is being offered with a 280-horsepower, 2.8-liter, V-6, turbocharged engine, and either a six-speed manual or automatic transmission.

Saab is selling the XWD system not just as a good weather-beater, but also as a high-performance tool for driving enthusiasts. Using four wheels to power the car and act as receptors to electronic controls that prevent skids and slips is better than two wheels any day.

And on a multifaceted test track in Sweden, our test car showed a remarkable adaptability, the likes of which I've only encountered recently in the new Porsche Cayenne SUV on a test track in Texas.

We went from gravel to hard turns on rough pavement, and negotiated a tight slalom of cones without knocking any over. From there, we moved on to sharp bends on a dry racetrack. All was seamless. Then there was the simulated "ice" track -- mirror-smooth concrete kept wet by a constant spray of water, along with a course to negotiate. There also was an "emergency lane change" through a set of cones meant to simulate danger at highway speeds.

In several instances, I could feel the car try to break away. But, right away, I could sense the booming "voice" of the electronic controls and Haldex system saying, "Oh, no, you don't!"

The XWD system is fully automatic and does such things as send power to the rear wheels as soon as it senses an aggressive takeoff. Voila, the torque steer that is common to front-wheel-drive cars is suddenly gone.

The electronics serve to monitor a driver's input, the car's attitude, and driving conditions, distributing torque front-to-rear as needed. They also can send it corner to opposite corner. The variable torque transfer of an active rear limited-slip differential allows the power swap between rear wheels. In this case, the limited slip uses wet, multiplate clutch units. The "grip" between the plates can change and thus allow rotational difference between the two shafts of the rear axle.

Throttle and braking input, via electronic monitors, also act to control the car by reaching out to troubled wheels.

On the highway, when traction and grip is not an issue, only between 5 and 10 percent of the engine's power goes to the rear wheels. That provides the heavier tactile sense of front-wheel-drive and saves on fuel. Transfer to the rear occurs only as needed.

The XWD models could go on sale late this year, or by spring at the latest. While the XWD system is featured on just a couple of models for now, you can be sure that no car company would develop something this sophisticated without the intent of spreading it through its lineup. And remember, General Motors Corp. owns Saab, so there may be hope for some US versions of this system as well.

None of us will ever be Erik Carlsson, but should we accidentally find ourselves in one of the precarious positions into which he often put himself intentionally while racing, this car will do for us what he so often did for himself -- calmly fix it.

Royal Ford can be reached at ford@globe.com.

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