Tire Size: Is Bigger Really Better?

When it comes to tire size bigger may be a recent trend, but that doesn’t mean it’s right for every driver or car. Most new vehicles are equipped with 16- to 18-inch tires. However, aftermarket plus sizing increases wheel diameters from 1 to 8 inches beyond the original tire size.

Do these enhancements add value beyond the aesthetic? Here’s what you need to know:

Don’t Judge a Book by Its Cover

A bigger wheel size might look buff, but it reduces the height of the tire sidewall (the area between where the tire meets the wheel and the pavement) that will still fit within the stock wheel well. More sidewall creates a cushion between your vehicle and the road. Meaning that many vehicles with 18-, 19- and 20-inch tires have narrow sidewalls. So although the end result may be improved handling and a trendy look, it also makes the car less comfortable to ride in and drive.

Pros and Cons

The shorter and wider a tire is, the better the cornering and handling. Other benefits of wider tires include improved turning radius, ability to accelerate and stopping power. These larger tires also influence other ways that a vehicle responds to the road, including traction control and stability.

There are, however, some drawbacks. For instance, larger diameter tires and wheels put more strain on the brakes in order to stop. This can lead to increased wear on the brakes and thereby accelerate the maintenance schedule and how often you’ll need to replace them. It also takes more engine power to start rolling a larger diameter tire/wheel package, which adds an increased burden to the driveline. In addition, the speedometer will no longer be calibrated once the rolling diameter has changed.

Other Considerations

Some people choose to install a much taller tire to increase ground clearance for off-road vehicles. While other drivers perform these modifications mainly for appearance. Put any factory stock Jeep and a modded out beast on 44-inch tires side-by-side and it won’t take long to decide which cuts the more imposing figure. But remember upgrading the brakes may be necessary, as well as gear ratio swaps, once these changes are made.

A wide tire and a change of wheel offsets (the distance from the hub mounting to the center of the wheel) can also cause rubbing on the inside of the wheel well and the outer fenders. The condition may be addressed by “rolling” the fenders to create more clearance. But this modification may then lead to other issues such as steering and suspension geometry, which can have an effect on vehicle alignment and stability.

Choosing to change your tires and wheels from the stock size to a taller or wider model has both advantages and disadvantages. While clearly not a necessary upgrade for most daily drivers, car enthusiasts who put a premium on aesthetics and performance will gladly accept a few potential negatives to help their ride stand out from the crowd.

Check out all the steering and suspension parts available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on tire size, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

Photo courtesy of Wikimedia Commons