Tyres – very important things! This weekend’s racing meet has been interesting in that we’ve had a variety of weather conditions – very wet on Saturday, slightly damp Sunday morning and dry in the afternoon, with the rain turning up YET AGAIN for a bit of fun.
I was talking with one of the Porsche team mechanics about who dictates what tyres get used – slicks or the treaded ones. Under wet conditions track officials tell teams that treaded tyres must be used, dry – you can use the slicks. But under damp conditions it’s down to each individual team – so pressure is on to make the correct call, it can make or break a race.
Why are racing tyres for dry conditions smooth? I’ve been told basically there’s more ground contact (those wee grooves in the treaded tyres are essentially negative space), so more control. The drivers do a hotlap first, the rubber heats up and gets sticky – better traction.
For the wet, water needs to be taken away from the contact area in an organised fashion – by way of the tread grooves.
However – I was also told that treaded tyres are softer than slicks, and as you go around a damp track it will dry out where most of the cars are driving. The drying will cause the treaded tyres to heat up and get softer – not good for speed.
That’s my very basic take on it – if you can add to that (or correct it!) please feel free to comment.