One of the easiest ways to improve the performance of your vehicle is with Plus Sizing wheels and tires.
Plus Sizing refers to tires that are wider and have a shorter sidewall. The result is a larger contact patch and a sporty look.
Drivers choose Plus Sizing to improve:
- Steering response
- Cornering ability
- The look of your vehicle
What’s “Inch Up”?
“Inch Up” is the process of mounting a lower aspect ratio tire and larger diameter wheel on your car. This creates a larger contact patch and a shorter sidewall.
Why “Inch Up”?
“Inch Up” to improve your vehicle’s performance and appearance.
- Increased Steering Response
- Improved Dry Handling
- Enhanced Cornering Ability
- Aggressive Good Looks
How Can You “Inch Up”?
“Inch Up” with the experts in plus sizing.
- Innovative Technology
- Precision Fit
- Wide Size Selection
- Proven Performance
“Inch Up” may be done in several ways. The most popular are:
1. Plus Zero
This method utilizes the same wheel diameter as Original Equipment(OE), but incorporates a tire with a larger than OE section width and smaller than OE aspect ratio. For example, replacing an OE 175/70R14 tire (on a 5.5-inch wheel) with a 195/60R14 tire would be a proper Plus Zero fitment. Note that this may require a replacement wheel to maintain proper rim width for the new tire.
2. Plus One
This method utilizes a one-inch larger diameter wheel, in conjunction with a tire of a one-step lower aspect ratio. An example of an appropriate Plus One fitment is to replace an OE 175/70R13 tire (23-inch overall diameter) with a 185/60R14 tire (22.9-inch overall diameter). Note that this method always requires a replacement wheel.
3. Plus Two
This method utilizes a two-inch larger diameter wheel, in conjunction with a tire of a two-step lower aspect ratio. An example of an appropriate Plus Two fitment is to replace an OE 175/70R13 tire (23-inch overall diameter) with a 195/50R15 tire (22.8-inch overall diameter).
An independent research company recently conducted a test to determine the effect “Inch Up” has on handling. Included here is an abbreviated summary of the test results.
The vehicle used for this comparison was a 1989 Mazda RX-7 SE. The original equipment tire is a 185/70HR14, and is mounted on a 5.5-inch wide wheel. The test was conducted on a dry asphalt surface. As the results from the lateral acceleration and handling course indicate, each successive plus size led to a noticeable increase in handling performance.
When changing to a non-OE tire size, always consult the load/inflation charts to determine proper inflation pressure to maintain OE load-carrying capacity. Talk to your local CountryTire store about your Plus Sizing options.