Upgrading Your Tyre Size
This is a great article from Pirelli tyres.Hence, explains in short, what happens if you change your tyre size. Naturally, most drivers keep exactly the same tyres as were supplied with e new car. Wheels and tyres are designed by the tyre manufacturers and the car manufacturers. Of course, some tyre dealers also sell wheels. Therefore, these people become experts at fitting other tyre sizes. Thus also recommending fitting other sizes of wheels and tyres.
Usually, it is the younger driver that wants to upgrade his car onto different wheels and tyres. I must admit that this is a market that we at Pellon Tyres struggle with? People do not want the wheels that we keep in stock. Accordingly, they only want the wheels that you can’t get. However ,if the driver does fit new tyres and wheels it is important that the correct ones are fitted.
Wider wheels are usually wanted. Because of this it is important that the correct height is kept. This is known as “overall diameter”. There is an amount of tolerance involved. Thus, this is about 15%. You can get official tyre company charts that give you the correct change of tyre and wheel size. It is also worth remembering that your tyre size affects your speedo reading.
TO double check your speedo. Then you can check the reading against your SAT Nav.