Tire size help

[Mineral///M4]

The facts

09 135i AT
170k miles
Continental tires
18 inch factory rims.

I want to move to Michelin Pilot Sport 4S

Please what tire sizes should I feel save with putting on my car. I am having a hard time finding 215/40/18 for the front. I can find 215/35/18 For the front. In the back I typically run 255.

[Lester]

225-40 on the front 255-35 on the rear.

[Just Apex It]

Originally Posted by Lester

225-40 on the front 255-35 on the rear.

I ditto this. You can upsize by one and still be within the manufacturer recommend tire sizes for those width wheels of 7.5" and 8.5". An abundant amount of different tires in those size.

[Tommm]

Tire Rack has rim recommendations on their site when you spec a tire. I had 245s on 7.5s. I would have preferred an 8.0, but they weren't available with my offset. 245 on a 8.0 was within spec, and was on a track car and they worked fine, and were safe too.

[Converted1]

I upsized to the 225 front and have not regretted it one bit.

[ShocknAwe]

At one time I had 225/255 and it works great

[tock172]

Been running an upsized set of 225 and 255-section Michelin PSS for years.

[Mineral///M4]

Spacers up front w/ the 225’s???

[Gangplank]

Originally Posted by Alpine1

Spacers up front w/ the 225’s???

No need. I'm running the stock wheels and a set of Firestone Firehawk Indy 500 tires. 18" 225/40 & 255/35. No spacers needed or mods needed. They work great and cost is good too.

I did do the alignment pin mod & m3 front control arms. Both add some front camber but its not needed to run the tires.