My summer tires were scrap last year, and now I am due to swap out my winters to summers, so am on the hunt for summer tires. I first usually look around to see if I can find a sweet deal on some slightly used tires with tread left (7-8/32). Most of the 275/45 I was finding were less than ideal, BUT I did manage to find a really nice set of 255/50. I plugged in the numbers into the calculator and it gave me a +1% in diameter, so it is pretty close to OEM.

Would you guys come to the same conclusion ?

My bigger worry was the narrower tire fitting onto the same stock 20" rim, which from what I understand is 9" wide. When looking up info for 9" wide rims, it says that the minimum width tire to mount on a 9" wide rim is 235, and IDEAL would be 245-255, which happens to be the width of the tire I was looking at above (255).

Note: 255/50 installed (Hankook Ventus), and I can see the lip of the rim exposed, where as before it was covered nicely with the fatter 275/45.

Which made me think, why the heck would Audi slap a wider 275 tire onto a 9" rim? Isn't that an issue ?? Or perhaps, because I have the S-Line 20's, maybe my rim is 9.5", hence the wider 275 tire ??

Trying to understand Audi's logic on the 275, and also trying to feel comfortable that by dropping down to a 255 I will still be ok on that OEM rim.

Thanks
Neil