Anyone know why they fit W rated tyres good for 168mph to the vRS?

I fancy a set of Yokohama 539s but they are V rated which is 149mph. Is there some issue with the loading due to the heavy engine or extreme torque of the motor?

I would think both.

Check with your insurance company. I know that some insurance companies will not pay out if non-factory rated tyres were fitted.

There is a load rating as well as a speed rating. I would always recomend Z rating or above for any car that isn't a shopping trolly !

As long as the load index is the same or higher, it shouldn't be dangerous. But as said, check with the insurers.

The speed rating is for a constant speed, and I'm sure you won't be doing 149mph solidly for any amount of time in your vRS

Anyone know why they fit W rated tyres good for 168mph to the vRS?

I fancy a set of Yokohama 539s but they are V rated which is 149mph. Is there some issue with the loading due to the heavy engine or extreme torque of the motor?

Certainly Mark 2 Mazda MX-5s were fitted with higher rated tyres than the maximum possible top speed would require. It's said this is because the stiffer sidewalls benefit the handling - and yes' date=' the insurance issue has also raised its head there with people finding they can't downgrade the tyres having consulted their insurers.[/color']

The Wheel & Tyre Bible (see link below) is worth reading. This is what it has to say about speed ratings:

All tyres are rated with a speed letter. This indicates the maximum speed that the tyre can sustain for a ten minute endurance without coming to pieces and destroying itself, your car, the car next to you and anyone else within a suitable radius at the time.

http://www.chris-longhurst.com/carbibles/index.html?menu.html&tyre_bible.html

http://www.dunloptyres.co.uk/ourTyres/car/pattern/standard/