[335imax]

Was thinking of giving my 18x8 sportline wheels a wider stance in the rear only. Anyone run 255/40/18 on a square rim setup? Was going to leave the front alone at 225/45/18 and just change the tire on the back. I am curious if people have done this and opinions. I love the look of these wheels, but need more traction in the back.

[wdeerfield]

i dont think you can do a 255 on an 8" rim. widest recommended is a 245

[thejeremyman9]

Originally Posted by 335imax

Was thinking of giving my 18x8 sportline wheels a wider stance in the rear only. Anyone run 255/40/18 on a square rim setup? Was going to leave the front alone at 225/45/18 and just change the tire on the back. I am curious if people have done this and opinions. I love the look of these wheels, but need more traction in the back.

I asked basically the same question but for stock staggered 19s (see maximum tire size thread). I was told not to go wider than 245 on a 8'' rim. However, in other threads, i saw someone specifically state they were running 255s all around on stock rims. Note you would need to go down in aspect ratio if you go from 225 to 245. Not critical if you are RWD but you want to keep overall tire diameter similar front and rear.

Also, are you saying that your wheels are 18x8 all around? I thought even the 18s were staggered 8 and 8.5 wide.

[335imax]

All are 18x8 225/45/18 is exactly the same diameter as 255/40/18. Guess I could do 245/40/18 which is really close

[thejeremyman9]

Originally Posted by 335imax

All are 18x8 225/45/18 is exactly the same diameter as 255/40/18. Guess I could do 245/40/18 which is really close

Interesting, didnt know the stock 18s were square. In any case, you should be fine with 245/40/18 on a 8'' rim.

Also, for traction, stickier tires helps more so than adding section width (especially after a point). The jump from 225 to 245 should be noticeable though.

I spin 1st from a dig and 2nd from a roll with FBO, MHD 2+ tune, and summer tires on a clean dry road.

[335imax]

Any opinion on running a slightly wider tire on the rear with a square wheel setup?

245/40/18 or 245/45/18

[alohasurftoad]

https://f30.bimmerpost.com/forums/sh...MMMM+new+tires

https://f30.bimmerpost.com/forums/sh...F45%2F18+dummy

245/40/18 square or 235/45/18 square, Michelin Pilot Sport 4S. in addition to widening, the brand, model, category of tire you choose is just as important especially if you're looking for more traction.

[perezr10]

I've been running 255/40's for 3 years with no issues. It's a square setup on the 397's. I love the look. It was their identical diameter to the 225s which made me choose 255s instead of 245s.

[perezr10]

One more to give you more of an idea on how they'll end up. Although, I am using some 3mm spacers all around.

Since it's a square setup, I'm getting more life out of the tires since I can rotate every 3K. Otherwise the rear tires need to be replaced way to quickly.

[thadoggfatha]

Originally Posted by perezr10

I've been running 255/40's for 3 years with no issues. It's a square setup on the 397's. I love the look. It was their identical diameter to the 225s which made me choose 255s instead of 245s.

I myself am interested in running a set of 255/40/18 my wheels are the style 397s but my rims width on the front and rear is 8J.
Was wondering if that’s the same setup your running and if there is any rubbing etc!

Sean

[captainfast]

You won't be able to run 255/40/18 on 8J rims. Minimum is 8.5J to use that tire size.

[perezr10]

Originally Posted by thadoggfatha

I myself am interested in running a set of 255/40/18 my wheels are the style 397s but my rims width on the front and rear is 8J.
Was wondering if that's the same setup your running and if there is any rubbing etc!

Sean

Yes, they're 8J. No rubbing at all on the stock sport suspension.