Going from staggered to square, any problems?

[DIVx0]

I've searched for this and I could not find a satisfactory answer.

I know going from staggered widths to square widths is not a problem and sometimes preferable, however I am unsure about going from staggered diameters to same.

I am putting winter wheels/tires on my M3CS (steel rotors) and the sets i'm looking at are:
18x8 BBS SR Wheels
245/45R18 Pirelli Sottozero 3 RFs

This works out to rolling diameter of 26.7" all around

Stock setup for my car is:
255/35R19 Front
285/30R20 Rear

Which works out to be 26" front RD and 26.7" rear RD

I assume the difference is negligible and should not cause a problem BUT I was hoping I could get some input from you all. The parts dept at my local dealership said "should be ok" but that does not fill me with confidence.

Maybe I'm overthinking it?

Thanks in advance

[halfempty]

Lots of guys run square setups with 245/45/18 or 255/40/18 without issues.

Check out thread

18" winter wheel options/pricing - let's list them here https://f80.bimmerpost.com/forums/sh....php?t=1046081

[wsccsw13]

A square setup (diameter as well as width is fine). I run a square setup for the track of 275/35 R19 and BMW sells a square setup for winter for the M3/4. This comes up a lot and to clear the air I emailed Bosch who developed the DSC/TC system with BMW and supplies it too them. I asked if going from staggered to square diameter would adversely affect the system and they replied:

“Dear Mr. _____,

Thank you for your question and interest in our mobility solutions.

The dynamic stability control is very robust, which means that it can cope with all approved tire combinations. Any measurable differences in the tire circumference are detected and compensated by the system. The angular speed of the wheel is corrected without any changes in the application parameter.
Mit freundlichen Grüßen / Best regards”

So the system detects and adapts with a little time and some miles.

[DIVx0]

Originally Posted by wsccsw13

A square setup (diameter as well as width is fine). I run a square setup for the track of 275/35 R19 and BMW sells a square setup for winter for the M3/4. This comes up a lot and to clear the air I emailed Bosch who developed the DSC/TC system with BMW and supplies it too them. I asked if going from staggered to square diameter would adversely affect the system and they replied:

“Dear Mr. _____,

Thank you for your question and interest in our mobility solutions.

The dynamic stability control is very robust, which means that it can cope with all approved tire combinations. Any measurable differences in the tire circumference are detected and compensated by the system. The angular speed of the wheel is corrected without any changes in the application parameter.
Mit freundlichen Grüßen / Best regards”

So the system detects and adapts with a little time and some miles.

Thank you, that's exactly the answer I was trying to get out of my service department