How much difference can winter tyres make to your car’s performance and safety?
In snowy conditions, choosing between winter and summer tyres is like choosing between crampons and slippers, but plenty of British winters pass with barely a flake touching the ground. So it’s understandable that most of us are reluctant to fork out for winter tyres.
Yet tyre makers claim there are benefits when temperatures dip below 7degC, especially when it’s wet. In other words, the conditions you’ll typically find during a British winter. Are we missing a trick?
To see for ourselves, we’ve come to Pirelli’s Vizzola test track in Northern Italy. The temperature is hovering at a few degrees above zero while sprinklers keep the surface greasily wet. It’s here that we’ll compare winter and summer tyres’ performance during 0-62mph standing starts, braking tests and full lap times.
But, there’s a twist: we’re equipping our BMW 435i with 18-inch Pirelli Sottozero 3 winter tyres and pitching it head-to-head against an M3 on its factory-fit 19-inch Michelin Pilot Sports.
The 4.0-litre V8 M3 has 112bhp on the 3.0-litre turbocharged 435i, as well as uprated brakes and suspension, so it should monster the 435i. But can the 435i’s Sottozeroes overhaul the M3’s performance advantage? Time to find out…
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0-62MPH STOPPING DISTANCE
Failing to launch your M3 to 62mph as quickly as a 435i might dent your ego, but it won’t dent your car; losing the edge on braking performance might. So we get our two test cars up to speed and sit side-by-side at a constant 62mph, then stand on the brakes as hard as we can at a marker cone.
The 435i’s brake pressure builds quickly under my foot and as I push harder I feel the ABS pulse. There’s no twitchiness, though, just a very controlled stop that forces me hard against my seatbelt.
Given the conditions, the M3 is actually quite impressive, pulling up quickly and under total control, and when we turn off the sprinkler system and allow the track to dry a little, there’s barely a car length in it.
But you don’t need to look at the data to see the extra metres the M3 requires in wet conditions, and after several attempts the figures settle at 40.6 metres for the 435i compared with exactly 50 metres for the M3 – a 20% difference. It could be the difference between having a nasty accident and a near miss.
>> Missed Part One of 435i vs M3 V8? Click here to catch up