What tyre size is legal?
The overall diameter of a wheel and tyre fitted to a vehicle must not be more than 50 mm (4wds) or 15 mm (other vehicles) larger than the largest tyre size listed on the tyre placard and not more than 15 mm less than the smallest tyre size listed on the placard on all vehicles. It’s highly recommended to use the exact tire size recommended for your car. However, in a pinch the tire width and aspect ratio can be changed slightly and still fit on your rim. Although this will still work, keep in mind it may have adverse effects on the performance of your car.