Does going from a 215 to a 205 series tire give me better performace in snow? I have been told that it does not.
It’s nor “series”…It’s the SIZE of the tire you are referring to. Stick to the recommended correct size tire for your vehicle…Never install smaller tires than recommended.
My guess is you are looking at 215/45/17 vs 205/50/17.
For winter 205/50/17 are better as they will offer little better traction and less prone to damage due to higher profile. Speedometer will only be slightly off if 215/45/17 is standard size.
I know all this as my car uses 215/45/17
A snow tire will work better in snow. If you live in snow country, you might consider a second set of cheap steel wheels (if they will fit over the brakes) with taller and narrower snow tires for the winter only. When teh snow melts, put the good wheels back on.
The number you alllude to is the width of the tire at its widest point, the “section” width. While a narrower tire of the same make and model will penetrate the snow better when all other things are the same, in order to have this effect you’ll need to adjust the “aspect ratio” accordingly to ensure the same rolling diameter. That’s the other number that follows the section width number. It represents a ratio of the sidewall height to the section width. A 205/50x17 will have about the same rolling diameter as a 215/45x17. By keeping the sidewall roughly the same you keep your speedo and odo accurate, procide the same pothole protection, and do not offset the traction gains of the narrower width by adversely affecting the handling too much.
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