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Should you buy winter tyres: CAR puts them on test
Stuff We've Done
04 December 2012 11:11
Do winter tyres work? We've explained how snow tyres work in our separate story here, but now it's time to put them to the test. We've tried cold-weather rubber in a wide range of cars, to see if they really are up to the hype.
The venue? Porsche's Experience Centre at Silverstone.
The cars on test: a winter tyre workout
CAR arranged back-to-back comparisons between regular and cold-weather tyres on a variety of popular cars: the new Honda CR-V 2.2 DTEC, Ford Focus ST estate, Jaguar XF 3.0 Diesel S and Lotus Evora S. Two models of each were provided, with and without snow tyres.
That Lotus happened to be road test editor Ben Pulman’s ex-long term test car shod in winter rubber – it's good to see it’s still leading charmed existence as its maker intended!
Do you really need winter tyres on a 4x4?
Perhaps the most interesting test was the Honda CR-V, because this is, after all, a part-time 4WD soft-roader – exactly the sort of rough-and-tumble crossover buyers flock to because they like the pretensions of all-weather ability. Well, dispel those assumptions, because on normal tyres the CR-V was a law unto itself on the low-grip ‘ice hill’. Despite the vocal protests of the ABS, and best efforts of the all-wheel drive brain, the CR-V responded to steering inputs like a fairground dodgem, where you twirl the wheel to engage reverse but become a drifting duck in the meantime.
Braking performance, or the total lack thereof, was downright frightening. The winter tyre-shod car was by no means stuck to the road, but it allowed measured braking and steering with very little electronic interference. The glassy nothingness of response through the steering also disappeared. No matter what the brochure says, this test suggests you need cold-weather tyres fitted before you can tackle icy roads in real confidence – even if you drive an SUV.
How does your faster-than-average family hatch cope with snow tyres?
The Ford Focus ST might be a hot wagon, but the front-drive chassis is still by far the most common layout for most British drivers. How did it handle the twisty low-grip track? Rather well on both sets of tyres, it has to be said. On the dry track, temperatures simply weren’t low enough to fully exploit the softer compound winter tyres. The regular-rubbered car did feel more tail happy (no bad thing for giggles) and struggled to put moderate power down in lower gears even with the traction control on. Still, we’re talking about a 247bhp hot rod here: both cars performed admirably.
Can winter tyres teach an ageing executive saloon new tricks?
Our time in the rear-drive, auto-only XF was limited to the kick-plate at the Porsche centre. Simply, as you drive onto a wetted, slippery surface, a hydraulic floor panel shifts as it senses the car’s rear wheels passing over it, causing the car to snap into oversteer. The cold-weather tyres found more front-end grip with which to use opposite lock in stopping a spin, but traction control on or off, the 275bhp, 442lb ft XF lit up its rears easily, regardless of tyre choice.
It goes to show that although the winter tyres are better at maintaining traction in the slippy stuff, they won’t necessarily make your car noticeably easier to handle once traction has been lost. Having said that, if you prefer to stand on the brake pedal rather than attempt to catch your sliding car, winter tyres stop you sooner.
And how does a world-class sports car take to winter rubber?
Finally, to the Evora S. How does a 345bhp supercharged sports car take to wobbly winter rubber on a mild afternoon? Predictably, this was the only test of the day where the winter tyres performed worse than their summer counterparts. Thanks to the more malleable treadblocks, understeer entered the fray (unheard of in the Evora) and the front sidewalls suffered as the Evora leant over hard on the winters’ sidewalls. Asking for full power on corner exit even through second and third gears had the traction control light blinking like a nightclub strobe light, with marked delays in power delivery.
By contrast, the summer rubber Evora was the sublime machine we’re familiar with at CAR. Well damped, lovely communicative steering (that the Porsche bods would do well to emulate in their confounded electric set-ups) and, incidentally, much preferable with the paddleshift ‘IPS’ auto than the notchy, obstructive manual.
Should we be ‘blessed’ with a white Christmas, it’s heartening to know that even high performance mid-engined cars aren’t necessarily consigned to the garage. They can be made fit for duty – at a price. A fulsome £500 for a set of Yokohama 275-section rears, to be exact – and another £195 each for the fronts.
Winter tyres: the cold, hard facts
You can be sure that cold-weather tyres are substantially better performers in wintry conditions. And I mean potentially bumper/no-claims bonus/life-saving. In wet conditions, they can stop an average family hatch from 50mph 18m shorter than regular rubber. Yet despite being mandatory in winter months in Austria, Switzerland and Germany, only 3.1% of the new tyres sold in the UK in 2011 were winter tyres. It seems our ever-unpredictable weather is a factor: drivers simply aren’t willing to shell out around £150 a corner for extra tyres if they may end up only compromising handling in the event of a mild winter.
It comes down to what price you place on the peace of mind offered by more appropriate rubber every time the road is wet, icy, or it’s simply cold enough to see your own breath. Some tyre-fitters and car makers are now offering storage schemes whereby your summer wheels will be looked after free of charge when not in use, encouraging motorists to invest in cold weather tyres.
From driving a diverse array of cars with wilding varying power, drivetrains and set-ups, you can be sure of one other thing: take it from us – it’s the tyres that’ll look after you this winter, not necessarily the car they’re fitted to.
>> Click here for the science of winter tyres: how snow tyres work