Tire size questions

[Dah.car36]

I just purchased a F: 255/35/18 and R: 275/35/18 and I was wondering if those dimensions and tire sizes works on an e46 m3 ? I did the calculations and it’s .8 of a difference in diameter being larger in the rear … I read it’s okay but just wanted your guys second opinions haha

[Tbonem3]

The e46 m3 wants equal rolling diameters. So besides a square set up, the appropriate mix would be 235/265, 245/275 or 255/285 with the front tire having one size larger profile - 245/40/18 & 275/35/18.

A 255 on a typical 8 or 8.5" rim is overkill. What are your wheels?

[Dah.car36]

The e46 m3 wants equal rolling diameters. So besides a square set up, the appropriate mix would be 235/265, 245/275 or 255/285 with the front tire having one size larger profile - 245/40/18 & 275/35/18.

A 255 on a typical 8 or 8.5" rim is overkill. What are your wheels?

I’m currently running a 18x9.5 in the front and a 18x10.5 in the rear !

[Tbonem3]

Yes, me too. It's a difficult spec to fit esp if you want some good meat on there. Depending on the offset, 10.5" is a little dificult to fit AND put a 285 tire on. You'll have much better luck with 275 or even 265 if you're not willing to pull or shave the fender.

While 9.5" is pretty wide up front, you could easily fit a 245 which would then pair well with 275 or you could run 265 (but step down the profile). Either 265 square (like me now) or 265/276 (what I ran a couple of years ago. Close enough to stock ratio).

I think 255/35 is a little too small up front and 255/40 is too big. I'd go 245/40 or 265/35. At least you're in the ballpark. And worst case scenario, DSC gets little more disturbed, but you can turn it off or maybe even code in Mtrackmode dsc which is less sensitive.