When you buy new tires or wheels you consider the minimum wheel width. However, for maximum performance (i.e., the widest tire patch), you should also consider the section width. It is important to know that narrower or wider wheels will have a decreased, or increased section width. The accepted standard is for every 1/2" change in rim width, the tire's section width will change by approximately 2/10" in whatever direction the wheel width changes from the minimum wheel width. As you change section width, the contact patch of the tire will change, but within the acceptable width range, you generally won't have a huge static contact patch change assuming you change the inflation as well. As an example, you can safely mount a 275/40-20 tire on a wheel with a width measuring 9-11 inches. However the recommended section width is 9.5 inches. So, if you mount this size tire on a 9 inch wide wheel, you will not maximize its tread contact area. For specific information see: https://www.tyresizecalculator.com/tyre-wheel-calculators/wheel-rim-size-calculator
Yea, but. . . . . I still say the tire should be at least as wide as the rim. I Hate the looks of the Rim being wider than the tire. Even my stock front 245/45/20 looked weird on my 9" SRT rims. And ha, I was right, you calculator shows they should be on 8" rims
It's not like they SHOULD be on an 8" rim but that's what the typical tire manufacturer based their design and published sectional width, on. There are cases where some tire manufacturers have actually recommended differently then what the typical recommendation charts show. As a point of interest you will note that the wider the profile is, the narrower the wheel is allowed to be. More room for flexing.
Tire Rack has an online configuration tool for your car. Plug in your details and they give you a list of wheels and tire sizes.
