How to change your tyre size

When considering a fitting a wheel of a different size to your car, it is important to obtain expert advice. Naturally a taller or shorter wheel will bring with it the need to fit a tyre of a different profile (height).

You must maintain a combined diameter of wheel and tyre that is as close as possible to the original so that the gearing of the car’s drivetrain is not adversely impacted. Doing so will also ensure that the ride height will not change significantly and the car’s safety will not be compromised. Before changing wheel and tyre size, etyres would recommend checking the guidelines set out by your car manufacturer and it is worth speaking to your insurer, too.

Many drivers choose to fit a taller or wider tyre for cosmetic reasons. The combination of a taller or wider tyre and a lower profile tyre can increase roadholding performance, although the comfort of the car’s ride will be reduced. Alternatively, a large wheel with a low-profile tyre can be replaced with the combination of a more standard wheel and a taller tyre. The latter is quite a common practice when fitting winter tyres to a performance car, for example.

Entering your current and desired new tyre size into the calculator below will enable you to see if this is a viable and safe option. If the percentage difference in diameter is more or less than 2.5%, etyres would not recommend this change.

Current tyre size
Tyre width:
Tyre profile:
Wheel size:
Overall diameter:
New tyre size
Tyre width:
Tyre profile:
Wheel size:
Overall diameter:
Difference in diameter: 0%Actual diameter change: 0mm
We recommend a MAXIMUM of +/- 2.5% difference

 

To buy new tyres for a new wheel, simply enter the new tyre size into the search tool at the top of the page and select the best tyre for your needs. Alternatively, if you would like to discuss the implications of changing wheel and tyre sizes, you can call our National Sales Team on 0800 028 9000 or 0333 323 9000 at a local rate from a mobile.