|December 20, 1999
Editor's Note: With this article AudiWorld is pleased to announce that we will be reprinting, on an ongoing basis, wheel and tire articles courtesy of The Tire Rack.
While Performance Winter tires may sound like an oxymoron in North America, their original European roots help explain their very existence. In Europe, where there are still some unlimited speed highways, the compromise in vehicle performance resulting from the use of "all-season" tires has never been accepted. So on a continent where driving is taken very seriously, only dedicated "summer" and "winter" tires are used to meet the prevailing driving conditions. However, several Central European highways, like Germany's Autobahn and Italy's Autostrada, require that even winter tires measure up to their high speed dry road driving conditions by providing enhanced handling and high speed durability.
Additionally, many European vehicle manufacturers and aftermarket vehicle tuners now produce high performance cars that require large diameter wheels and low profile tires to clear their massive brakes and still fit inside their wheel wells. Today therefore, tire manufacturers offer Performance Winter tires that are up to H-speed rated (210 kmh/130 mph) with profiles as low as 35-series for wheels of up to 18 inches in diameter.
And because winter tires have become increasingly popular in North America for sports cars, coupes and sedans, several tire manufacturers have imported their Performance Winter tires directly from Europe, while other manufacturers have developed new tires which emphasize the winter performance traits they think will better meet their North American customers needs.
In order to get a better understanding of the on-road and ice traction capabilities of several Performance Winter tires, The Tire Rack Team conducted a Ride & Drive comparing two new Performance Winter Category tires, the Bridgestone Blizzak MZ-01 and Michelin Pilot Alpin, to the Pirelli Asimmetrico Ice (which was introduced last year). In place of our normal test track drive, our team went to a local ice rink to experience the ice performance of these tires months before the first snow will fall in South Bend. And although it was 88 degrees and sunny outside, inside the air was cool and the ice was as cold and slick as polished intersections will be in the middle of winter - perfect conditions for getting the feel of winter tire ice traction and handling in a controlled environment. After the ice rink evaluation, we put the tires through our normal seven mile "Real World Road Ride" loop to evaluate each tire's road noise, comfort and handling traits. We used three 1999 BMW E46 Chassis 328i sedans fitted with their original equipment 205/55R16 size tires mounted on 16"x7.5" wheels.
This year we introduced several ice testing methods which help eliminate the affects of the driver's reaction time and reduces the possibility of driver error affecting the outcome of the tire's ice ratings. First, each car was lined up with its rear wheels on the goal line. Then as the car accelerated as fast as its traction control would allow, we recorded the time it took for the car to cover the final 60 feet to the center of the rink. This was immediately followed by ABS controlled braking. And finally, we tested each tire's ability to corner on ice as it negotiated the equivalent of a typical 90° right hand street corner while maintaining a predetermined speed. With traffic cones set every 6 feet along a line (representing the center of the road being turned onto), we could determine how tight an arc the tire's traction would allow the car to maintain.
Bridgestone Blizzak MZ-01 - Developed for use where ice traction is a priority, Bridgestone's nickname of "The IceGripper" for the Blizzak MZ-01 identifies it's one of the tires that takes an alternate approach to the Performance Winter Tire Category. While the Blizzak MZ-01 is available in the low profile, large rim diameter sizes, rather than focusing on traditional European dry road handling and high speed durability, the Blizzak MZ-01 follows in the tradition of other Blizzak tires by providing superior ice traction combined with good snow traction.
On the road, the Blizzak MZ-01 received the best ratings for its real world ride qualities, tied the Asimmetrico Ice for best noise levels, but was the slowest of the three tires in responsiveness. On the ice, the Blizzak MZ-01 was the easiest of the three tires to drive and provided the most traction for accelerating, braking and cornering. The Blizzak MZ-01's average 60 foot acceleration times on ice were 1.2 second (about 20%) quicker than the faster of the other two tires. In the cornering exercise, the Blizzak MZ-01 only hit an average of 0.5 cones, indicating that it could hold the tightest line through the corner.
The Q-speed rated Blizzak MZ-01 is available in the low profile, 15- through 17-inch wheel diameter sizes.
The Michelin Pilot Alpin lived up to its origin by being the most responsive of the three tires on the road, and this is where its European heritage really showed. The high speeds driven on the European highways in winter require that the Pilot Alpin meet the needs of drivers who frequently drive fast on dry highways, but must remain prepared for snow and slush.
On the road, the Pilot Alpin received good marks for its real world ride and handling where it was rated best for responsiveness, and was rated just slightly noisier than the other two tires. On the ice, the Pilot Alpin provided less traction for accelerating, braking and cornering than the other two tires. The Pilot Alpin's average 60 foot acceleration times on ice were about 1.5 seconds (25%) slower than the Blizzak MZ-01. In the cornering exercise, the Pilot Alpin hit an average of 3.5 cones, indicating that it couldn't hold as tight a line through the corner as the other two tires. The Pilot Alpin's focus on providing high speed durability and dry road handling prevented it from offering a tread compound that could match the ice traction of the other two tires.
The H-speed rated Michelin Pilot Alpin is available in low profile, 15-, through 17-inch wheel diameter sizes.
The Pirelli Winter Ice Asimmetrico is the Northern European member of Pirelli's Asimmetrico winter tire lineup. It is Q-speed rated (160 kmh/99 mph) and features a special blend of rubber resulting in a softer tread compound to better grip snow and ice at very low temperatures. Note: The other member of Pirelli's Asimmetrico winter tire lineup, the Winter 210 Asimmetrico, was developed for driving in the weather conditions of Central and Southern Europe, is H-speed Rated (210 kmh/130 mph) and features a standard winter tread compound.
On the road, the Pirelli Ice Asimmetrico received good marks for its real world ride and handling qualities (rated just behind the Pilot Alpin for steering response), and tied the Blizzak MZ-01 for best noise levels. On the ice, the Ice Asimmetrico provided good traction for accelerating, braking and cornering, but couldn't match the superior traction of the Blizzak MZ-01. The Ice Asimmetrico's average 60 foot acceleration times on ice were about 1.2 seconds (20%) slower than the Blizzak MZ-01. In the cornering exercise, the Ice Asimmetrico hit an average of 2.2 cones, indicating that it couldn't hold as tight a line through the corner.
The Q-speed rated Pirelli Ice Asimmetrico is available in low profile, 14, through 17-inch wheel diameter sizes.
In summary, here are three tires from the performance snow category that have slightly different characteristics. Which one is best? None of them all of the time. But each of them is best when their capabilities match your driving needs.
So the next time you go to an ice rink or watch figure skating or a hockey game on television, just remember that The Tire Rack Team has been on the ice and on the road so we can share our firsthand experience with you.