[JamesNoBrakes]

Originally Posted by JimGnitecki

Just an alert to keep in mind: Winter tires are usually narrow when compared to wide performance tires on performance cars. This is so they will cut THROUGH snow and slush versus "planing" on top of it before running you off the road.

Your neighbourhood tire professional can probably provide some experienced guidance on that.

It's probably unnecessary to say this to you, but you will not be able to use your car to much of its power potential in the winter.

Jim G

There's a good video on this which shows it's basically in the noise. I've seen others by the same author and their testing seems to be very exhaustive. Wide vs. narrow is far far less important than the actual winter tire and tread pattern. If you are going to be driving through 2 feet of snow, sure you might need a narrower tire for penetration, but if not, it's in the noise and doesn't matter. The results were the narrower tires DO accelerate/grip marginally better on snow and ice during acceleration...but they turn worse and brake worse than the wider tires, so you choose your poison. Also noted that any differences were even smaller on ice, they had to keep re-running the test to pick anything up between wider and skinnier. Overall, extremely small differences that are in the noise compared to winter tire differences overall. Also worth noting that your traction will then suffer on every other surface if you go real skinny 275 width tires are expensive and unless he's going to be driving only on cold surfaces, it would be best to downsize to smaller diameter and width rims so you can fit narrower tires. But that's from a cost perspective, not that he needs to run 205s or anything. If he's got an extra set of rims, it might make sense to go ahead and get them set up.

But to the actual question, there are usually 4 tire widths that fit on a rim, going from "stretched" to "bunched". In most cases manufacturers set it up so their rims have the max size already on them, so for my 11" rims, it's 305, so I can't go larger, but I can go smaller, like 295, 285 and 275. You have to refer to the tire mfr to get the actual correct numbers, but 95% of the time, this is the way it is. Sometimes you find an outlier where michelin for instance says I can run a 10mm wider tire than stock that is already at the "limit" for that rim, but that's rare. For a 10" wide wheel, you could go down as low as 255 safely. In most cases, it won't be recommended to go skinnier than that. Again, check with the tire manufacturer, they will say what the tire will run as far as rim widths.