| Test Summary | |
| Wet Braking |
Dunlop Winter Sport 5 Continental WinterContact TS 850 P Horizon Polar Star 5 |
| Dry Braking |
Dunlop Winter Sport 5 |
| Wet Handling |
Dunlop Winter Sport 5 Pirelli Winter Sottozero 3 Michelin Pilot Alpin 4 |
| Rolling Resistance |
Continental WinterContact TS 850 P |
| Noise |
Continental WinterContact TS 850 P Michelin Pilot Alpin 4 Hankook Winter i cept evo2 |
| Snow Handling |
Vredestein Wintrac xtreme S Horizon Polar Star 5 |
Luckily Auto Bild Sportscars have us covered with their latest ultra high performance winter tyre test. Auto Bild have taken eight UHP winter tyres in 225/40 R18 and tested them on a RWD Mercedes C Class across the usual range of snow, wet and dry tests and have included a summer tyre as reference.
Snow
During the snow tests the results were close, and the top places varied. The Nokian offered the best snow braking, the Pirelli was the fastest over a lap and the Michelin offered the best traction. All the winter tyres vastly out performed the summer tyre, which was unable to complete a snow handling lap, and stopped the Mercedes test car in 38.3 meters compared to 22.5 meters for the worst winter tyre on test (Horizon) and 20.5 meters for the best on test (Nokian)
Wet
Under wet testing, the summer tyre regained some points, winning the wet braking, handling and wet circle tests. The margin was greatest in wet handling, where the summer tyre had an average speed of 86.5 kph and the best winter (Dunlop) could only manage 83.2 kph. Under wet braking the margins were closer, with the Continental and Dunlop winter tyres stopping just 1.4 meters behind the summer tyre from 50 mph and the Dunlop and Pirelli beating the summer tyre under the straight line aquaplaning test.
Dry
Again in the dry handling and braking tests, the summer tyre showed its strengths. While the best winter tyre (Continental) could keep close to the summer tyre during dry handling, the dry braking test once again showed where siped tyres lose out, with the test winning Dunlop taking 43.5 meters to stop the car from 60 mph, compared to 36.3 meters for the summer tyre.
Results
What temperature where the wet tests taken under. I thought winter tires out performed summer tires at lower temperatures in the wet.
Auto Bild didn't list the temperatures. The tyre companies list 7c as the crossover point between summer and winter tyres, but in reality it's much closer to freezing.
How come the only "A" rated tyre for wet tracktion - Nokian D4 is showing such poor wet results ... just a five... Are Nokian bending the truth? Is the standard set up in a way that is not objectively measuring the behavioral/performance aspects of the tyre? Is the test bias towards the big 5 (4 in this case I see no Bridgestone and Goodyear they can not be worse than Horizon .....) ?
The tyre label only tests one category, wet braking, whereas Auto Bild have tested wet braking, handling, circle, and aquaplaning scores meaning they give a much more complete view of a tyre's wet performance.
That said, the Nokian was still only 5th best under wet braking (6th if you count the summer tyre), but we're extremely confident it is no test bias involved. Test conditions can change the balance of test performances but quite a margin.