If you want to change your car’s original tire and wheel size, then you need to consider some important factors. You cannot simply go out and put on a larger wheel and tire and expect your car to be the same. Your car is designed to roll on a specific wheel and tire size. Changes to either may start a cascade of handling and mechanical issues if you don’t plan carefully.
Below is more information about what tire and wheel size changes do to your car and how to change them the right way.
Reasons for Tire and Wheel Size Changes
Sometimes, people have practical reasons to change their tire and wheel size. One big reason to change wheel or tire sizes is if your car’s original tire size is difficult to find or unavailable. For example, many older cars with smaller wheels may have only a few tire options available in some areas. This can be a problem if you drive under certain conditions or have a certain driving style. If you size up, then you may find more tire options or variety.
However, for many people, a change in tire or wheel size has more to do with appearance than anything else. Many people use custom wheels to dress up and add value to their cars. Usually, this means a larger wheel size than before. However, some people, like those who own cars with lowriders, often downsize their wheels with wider rims.
Problems With Tire and Wheel Size Changes
One of the most common problems a change in your tire and wheel size can cause is an inaccurate speedometer. A larger tire has a higher circumference and fewer rotations as you roll along the highway. Because the tires rotate slower, the speedometer reads this as a lower speed. The faster your drive, the more your speedometer reading will be off. Your odometer will read lower, too.
Another issue has to do with wear and tear on suspension and brake components. Larger wheels and tires change the suspension angles and could even affect your transmission’s gear ratio. In some cases, brakes, especially anti-lock brakes, are affected. You may need to make suspension and brake changes to compensate for these problems.
Another consideration you should take into account is the amount of clearance you have for a larger tire. Some wheel wells are very tight. A larger tire or wheel may rub against your fender or your suspension, especially during turns. Larger tires and wheels also add weight that could reduce your car’s gas mileage.
Ways to Minimize Effects of Tire and Wheel Size Changes
You can minimize the possible effects of a larger tire and wheel with a few calculations and changes. If you minimize the overall size difference, then you may eliminate or reduce problems. For example, you may be able to increase your rim size while you reduce your profile or increase your width. If calculated correctly, you may end up with an overall wheel size similar to your stock wheels, but you will have the larger wheels you want.
Though many people recommend against significant tire and wheel size changes, you may be able to do it safely with the right precautions. If you don’t like the math calculations, then use a tire change calculator to see acceptable tire and wheel sizes for your vehicle. Some calculators also give you information about how your speedometer is affected.