This program is for comparing original equipment tire size to alternate after market tire sizes. All calculations are rounded up. Calculations are to be treated as approximate only, due to variations in how tires are manufactured.
To use this program you need to key in seven (7) pieces of information. The tire tread width, sidewall ratio, and wheel rim diameter from each of the two tires to be compared and a speedometer reading to be used to compute the effect the after market tire size has on your speedometer.
The following is an example to help to decode a tire size like 185/65R14
185 = tire width in millimeters, measured from sidewall to sidewall
65 = sidewall ratio, the ratio of sidewall height to tire width
14 = wheel rim diameter in inches
After keying in the seven (7) pieces of information, click on the "Compare Tires" button below to have the two tire sizes compared.
For information on stock and popular StarQuest tire selections, scroll to the bottom or click here.
Stock/Popular StarQuest Tires & Rim Specs: