Driving a car with high-performance summer tires is great – until the temperatures start to dip. 
Summer tires are standard equipment on many high-performance cars such as those from Audi, BMW, Mercedes-Benz, Porsche, and other manufacturers, and the tires are designed to provide optimum dry-conditions performance and good handling in wet conditions.

There is, however, a catch.  At 7° C (45° F), their compound loses adhesion and, as a result, they cannot be used safely under wintry driving conditions.

This is where winter tires (formerly known as snow tires) come in.  Today, drivers have a variety of options so there is no need to sacrifice handling and performance in colder climes.  A choice of tires that provide maximum traction on snow and ice (typically labeled “snow and ice” for that matter) as well as the relatively new high-performance winter tires are available.  There is also a third category, all-season tires, which, although beyond the scope of this review are generally a compromise.

Many countries mandate the use of winter tires from November through March but failing to fit winter tires can have far more significant consequences than a ticket: simply put, one’s ability to accelerate, steer, and brake can be significantly compromised without the right tires in wintry conditions. Cars with summer tires are an accident waiting to happen.

But most winter tires can have a dramatic (and negative) impact on how the car handles.   Especially at speed, they can be less responsive and somewhat mushy compared to the connected feeling one experiences when driving on summer tires.

Enter winter performance tires.  Even if you reside in an area that gets significant snowfall, you’ll probably be driving on plowed roads and this is where the argument for performance winter tires comes in.

To find out what the best tire is for winter conditions, we tested both sides of the equation.  The answer, we came to find out, is “it depends.”  As you will see, winter performance tires are a worthy substitute for summer performance tires in the colder seasons and snow and ice tires simply don’t have the dry grip that many drivers expect when they are not driving in snow and ice.

For our tests, we drove the BMW 335d in a variety of winter conditions, from the Roßfeldhöhenringstraße  near Berchtesgaden at an altitude of 1560 m to the cold and (this year) very snowy streets of New York City.

In Europe, the 335d was shod with Goodyear Ultra Grip winter tires on 17″ Borbet CA wheels, excellent snow and ice shoes which are endowed with superb grip.  But drive over 130 km/h (80 mph) on a dry road and the 335d starts to flounder and the steering starts to feel far less precise.

On snow, however, it was a different story.  For a drive through ski country, we found you couldn’t be on better snowshoes.  The Goodyears were confident and gripped the road without hesitation.

If you see more snow than pavement in winter, think Buffalo or Fargo (or Philadelphia and Washington D.C. this year), this would be the way to go.

Back in the States, we fitted the 335d with Pirelli Winter 210 Sottozero winter performance tires on 17″  BMW Style 159 wheels.  Pirelli engineers designed the Sottozero to be effective as the temperatures drop near freezing in autumn until they warm up in early spring.  Did this mean that drivers would no longer dread the day they had to give into Mother Nature and swap tires?  Judging by the 335d’s gains in acceleration and braking compared to the Goodyears, the answer is “you betcha.”

Pirelli explains that the Winter Sottozero tread compound utilizes cap and base technology that combines two different compounds.  The portion of the tire that comes into contact with the road uses Pirelli’s latest generation silanes to bind the silica and polymer to provide greater stability during hard driving in both wet and dry conditions, while the tire’s base uses nano-composites to provide stiffness that translate into enhanced stability and driving precision.

The asymmetric tread pattern has distinct inner and outer elements that Pirelli claims are able to combine traction in snow and ice with drivability on dry and wet roads.

Inside, these tires utilize the same ultra high-performance structures that are found in Pirelli’s summer performance tires, adding to the level of performance that the Sottozero can provide.  After several hundred kilometers in sub-zero February temperatures, we found we got no compromise sports-car like responsiveness on dry roads along with excellent traction and braking in New York City’s latest blizzard.

TIPS FOR WINTER DRIVING

• Use the correct tires (see main article). Store your summer tires carefully (we use Kurgo Tire Totes and label tote and tire each for proper reinstallation in the spring)
• Check tire inflation regularly.
• Know where you are going (and via what route) and check forecasts on the Web before leaving.
• Do not use cruise control on slippery surfaces (ice, rain, leaves, sand).
• Allow for conditions. Accelerate and decelerate slowly.  Slowing down on ice and slush takes longer.
• If you begin to skid, look and steer in the direction you want to go
• Don’t stop as you go up a hill.
• Take supplies along (snack, water, medication, blankets, gloves, shovel, and ice scraper).
• If you get stuck, stay with the vehicle.
• ICE – ICE stands for “in case of emergency” and storing an emergency contact in your mobile phone under the name ICE can help rescue personnel quickly locate a friend or family member if warranted.
  Winter Diesel Driving
  
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A World Cultural Heritage Site, Graz is Austria’s second largest city and is the capital and largest city in the province of Steiermark (Styria), a heavily forested region.  Graz was the Cultural Capital of Europe in 2003.

Leaving Roßfeld, the drive to Graz takes ca. 3 hours and is reached via a mix of Autobahnen, Bundesstraßen, and Landstraßen.  Only 150 km of the trip are via an Autobahn.

The route takes the 335d from the B999 (Roßfeldstraße) through Gmerk, where we cross the Austrian border and take the Dürrnberg Landesstraße through Hallein and continuing along the Salzachtal-Bundesstraße (B159) and then the Europastraße until reaching the Tauern-Autobahn (A10), which we take in the direction of Graz and Villach.

In the course of a 47-kilometer stretch on the Tauern-Autobahn, we go through five tunnels (Ofenauer Tunnel, Hiefler Tunnel, Brentenberg Tunnel, Zetzenberg Tunnel, and the Helbersberg Tunnel).

We continue on the E651 (which is first the B99 and then the B320) through Liezen, for ca. 75 km and join the Pyhrn-Autobahn (A9), which we take for the remaining 105 km to Graz.  The A9 takes us through the Gleinalmtunnel, with a toll of 7.50 EUR.

Exiting the A9, we reach the city center and the Grand Hotel Wiesler in just a few minutes.

Join us here for the drive.

The 4.60 € toll (for the car and one person, 6.50 € for two people plus children, going as high as 11.50 € for a car with five adults) is well worth the price.   A souvenir sticker is .50 € but a small brochure is handed out to all visitors.

To the north, one sees Austria, namely Hallein and Salzburg and, to the east, the Salzach valley and the mountains of the Salzkammergut.  In the southeast one sees the Dachstein mountains, which reach 2995 meters above sea level.

On the German side one sees the Hohen Göll, Kehlstein to the southwest and north of that the Berchtesgadener Alps.

In winter, ski lifts are everywhere as are skiers.  But many come just for the view and the many opportunities to sample good Bavarian Hausmannkost (plain fare).

Join us as we drive the Roßfeldstraße in the 335d.