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[TM9030]

I recently purchased a pair of 255/40 R18 for the rear and was thinking about going with a 225/45 R18 in the front in order to keep the tire diameter equal at 26". To fit the 255/40 in the rear I will have to roll the fenders a bit, it looks like I'm rubbing the slightest amount. Will I have any issues with the taller sidewall in the front since the width is pretty conservative at 225?

My current set up is:

Front: 225/40 R18
Rears: 255/35 R18

All I'm changing is the sidewall height to fill the extra space in the wheel well.

Thanks for any input

[b1aze]

You will likely run into issues rubbing on the fender clip in the wheel well depending on what your wheel offsets are.

Everything I’ve ever been told (especially from those whom I consider well informed) has been a taller tire is rarely better for performance so adding 1” diameter not only messes with your Speedo but actually reduces performance in just about every aspect.

[TM9030]

Originally Posted by b1aze

You will likely run into issues rubbing on the fender clip in the wheel well depending on what your wheel offsets are.

Everything I've ever been told (especially from those whom I consider well informed) has been a taller tire is rarely better for performance so adding 1" diameter not only messes with your Speedo but actually reduces performance in just about every aspect.

You are right going with a taller tire upfront will rub.
Going with a 45 sidewall upfront won't be the best option.

I ended up going with 245/40 in the rear and plan to go with a 235/40 or a 245/40 in the front. I want to fit the 245 in order to be running a square set up so the Speedo won't be affected.

I guess the threshold for diameter difference Is 2%.
Anything more is not recommended

[ShocknAwe]

Time to start playing with suspension which isn't a bad thing.

Don't mess with tire sizes unless you have a performance goal in mind.

[TM9030]

Originally Posted by ShocknAwe

Time to start playing with suspension which isn't a bad thing.

Don't mess with tire sizes unless you have a performance goal in mind.

That's very good advice, I've come to realize that wheel/tire fitments for the 135i is more tedious than I thought. The high offsets really limit us to certain wheel/tire sizes. I came from an Evo 8 and let's just say wheel tire fitment was easier with that car.

Looks like I have to do more research and familiarize myself with the 135i.

[b1aze]

Originally Posted by TM9030

You are right going with a taller tire upfront will rub.
Going with a 45 sidewall upfront won't be the best option.

I ended up going with 245/40 in the rear and plan to go with a 235/40 or a 245/40 in the front. I want to fit the 245 in order to be running a square set up so the Speedo won't be affected.

I guess the threshold for diameter difference Is 2%.
Anything more is not recommended

https://support.apexraceparts.com/hc...-Fitment-Guide

This is an excellent source of fitment info for our cars. You can sometimes cheat a few mm out further depending on the specific tire you select but these are about as dead-nuts on for fitment with our cars.