255-40-19 for winter?

[2kaccordocoupe]

Would this tire size on a square setup work for an m4?

9" wheel
Front ET:32
Rear ET:25+12mm spacer

Im basically taking a style 408m setup from an m5 and flipping the front and rears.

[Signature Wheel BMW]

From a fitment perspective, yes. However, square setup with traction control on (which is recommended for the winter) will create issues. I only recommend square setup for track with full nannies off, never for the street.

The OEM rear tire height is 2.5% taller than the front. When the front/rear are the same diameter, the ECU thinks the rear is slipping all the time (as the rear will turn 2.5% faster than usual). It will try to reduce engine power and apply brakes slightly to assist which this slippage that doesn't exist.

An M car's performance should never be sacrificed, even during the winter. Get proper wheels/tires for winter/summer so you'll enjoy your car all year round.

You can always use your M4's OEM 19s and run 1 size tire down front/rear. (i.e. 245/35/19 front and 265/35/19 rear) Otherwise, hit me up for reasonably priced Signature options.

[Ian1973]

I have a square setup, 245/45's and haven't experienced a problem with traction control.

[visi107]

BMWs winter tires package is also a square set up.

[ElSenor]

Just chiming in, I also run a square setup for winter. As has been mentioned, the BMW winter wheel package is also a square setup. You won't have any issues.

Edit:

Just to put your mind at ease, here is the stickied thread in this section. Scroll down and look at darmstadt's post at the bottom.
http://f80.bimmerpost.com/forums/sho...=945354&page=2

In short: 18" running 255/40 and 19" running 255/35.

[MaX PL]

Square setup here as well.

Youre not gonna get full traction from an undersized winter tire anyway so post #2 doesnt make a lot of sense.