You will need
- - table of basic parameters of tires;
- - a sheet of paper and a pen.
Look at the nameplate, in the doorway of the driver's side the recommended tire size. Write it down on paper or remember. Find the auto wheels with the same size using a measuring tape, measure the outer diameter of the tyre. Write this value down on paper. Driving the car to the pit and turn the front wheels fully, first one and then the other side. Measure with a ruler or tape measure the distance from the tire to the nearest structural member and record these values on paper.
Choosing tires, keep in mind the diameter of the future discs, and, depending on the size of future tires, pick up wide disks. The desired width of the disk equal to the width of the tread. It may be easier to find a disc of slightly larger diameter of the desired width. For example, to take the disks with a size of 14 inches instead of 13 and pick on them tires. This option would be even more advantageous in terms of durability, but more expensive.
Try to buy tires, the dimensions of which are approximately the same as recommended. For example, the manufacturer recommends a tire size of 175/70R13 86S. 175 is the width of the tyre in millimeters /70 – the height of the tire profile in percentage of width, R-13 – mounting diameter corresponding to the diameter of the discs 86 is the load coefficient, S is the speed index. It should be noted that the overall width of the tyre may be different from the width of the tread, so if you want a wider tread, then pay attention to this feature. Do not take tires with a low load and speed factors.
If you want to put on the car drives R16 is R13, locate the rubber of suitable width. Since R16 tyre width 175 mm does not exist, it is more realistic to find tires with a width of 215mm and wider. View your records and calculate how many centimeters you have in stock. Increase the width of the tires on more than the recommended 1cm, shorten the measured distance between the wheel and the body is 5mm. please Note that it is not desirable to increase wheel diameter more than 3 cm, as this will lead to increased fuel consumption and to the deterioration of traction characteristics of the machine. Select the appropriate tire and measure the diameter with a tape measure. Compare with the recommended wheel diameter. If exceeding the recommended dimensions of the future wheel within your design specification, you can buy your selected tires. Speed and load ratio in this case would substantially exceed the recommended that have a beneficial effect on the durability of the rubber.