Sponsored by The Tire Rack

[michaelalex17]

Hello everyone, I apologize in advance for this dumb question. I recently got style 193m wheels and tires for my xi wagon which have the following specs:

Front:
18x8 ET 34
225/40/18

Rear
18x8.5 ET 37
255/35/18

My problem is that the tires look like rubber bands for my liking. Based on these dimensions, are there different tire sizes I can use with these wheels that will have taller sidewalls without messing with my rolling diameter?

[tcphoto]

I like a little higher profile tire and went with 235/40/18 and 265/35/18 on my E92, you should be good on you Xi.

[whyzee125]

^ +1

[michaelalex17]

I'm currently already on 40 fronts and 35 rears. Am wondering if I can up those without messing up the speedo and transfer case etc

[335i54n]

235/40 265/35 would be my choice, you gain about .4" larger rolling diameter although 265 tires technically would be best on a 9" rim.

Another option would be 225/45 255/40 but imo that too much extra tire, you gain about 1" taller rolling diameter

https://tiresize.com/comparison/

[michaelalex17]

Originally Posted by 335i54n

235/40 265/35 would be my choice, you gain about .4" larger rolling diameter although 265 tires technically would be best on a 9" rim.

Another option would be 225/45 255/40 but imo that too much extra tire, you gain about 1" taller rolling diameter

https://tiresize.com/comparison/

Sorry if this is a dumb question but does the width impact the height? I'm already running 40 front and 35 rear but with narrower widths which I don't care about. Just care about sidewalk height.

[335i54n]

yes

[michaelalex17]

I thought the first number was the tire width, the second, was the height, and the third was the rim size. So you're saying a 265/35/18 has a taller sidewall than a 255/35/18 tire?

[335i54n]

yes, sidewall/profile height is a ratio/percent of the tire width. you could go 245/40/18 all around

[michaelalex17]

Interesting, thanks for the info

[alpinec1984]

235/45/18 and 255/40/18 PS4S on oem msports looks smashing on my 330I, people ask me all the time how much the car is dropped (zero) since the wheel wells are filled out so nicely. Nothing rubs, ever. Price was cheaper too. And the speedo is close to 100% accurate instead of 3.5% error as stock (read too fast).

[michaelalex17]

Sorry to revive an old thread but what about going with:

Front: 225 x 45 R18
Rear: 255 x 40 R18

Would that cause an issue with x drive?

[trohde78]

Originally Posted by michaelalex17

Sorry to revive an old thread but what about going with:

Front: 225 x 45 R18
Rear: 255 x 40 R18

Would that cause an issue with x drive?

Those would be fine as far as XDrive is concerned, as the diameter between the front and rear is the same. However, the diameter would be a full inch larger, which may lead to rubbing issues.

[michaelalex17]

Originally Posted by trohde78

Those would be fine as far as XDrive is concerned, as the diameter between the front and rear is the same. However, the diameter would be a full inch larger, which may lead to rubbing issues.

I have a decent amount of clearance I don't think it will rub, but want to make sure it's not going to make my Speedo way off or cause issue with x drive

[trohde78]

Originally Posted by michaelalex17

I have a decent amount of clearance I don't think it will rub, but want to make sure it's not going to make my Speedo way off or cause issue with x drive

Your speedometer would show about 4% slower than your actual speed.

[michaelalex17]

Originally Posted by trohde78

Your speedometer would show about 4% slower than your actual speed.

That's ok as long as it won't negatively effect my transfer case or anything else

[trohde78]

Originally Posted by michaelalex17

That's ok as long as it won't negatively effect my transfer case or anything else

The drivetrain will be fine as long as all of the tires are the same diameter.

[michaelalex17]

Originally Posted by trohde78

The drivetrain will be fine as long as all of the tire are the same diameter.

Got it thanks!