[tawhid]

Hey Guys -

I just purchased APEX ARC-8 18X9 ET30 for my 2017 BMW Xdrive. It's a square setup

Also, I got the Belestein B8 performance plus shocks and an MSS Sport Suspension kit.

** B8 performance plus shocks are shorter than OEM shocks and the MSS Sport suspension kit is supposed to lower the car 0-30mm

Question: Should I go for -

245/40 R18 Tires or
255/40/ R18

I will not do any spacers or Camber adjustments. Looking for Sporty daily drive.

I appreciate all your help.

Thanks,
tawhid

[Dagstar]

From what I've read most go with 255/40/18 all around, as did I. I've got the same wheel specs as you but with the VS-5RSs and am lowered a bit on coilovers, no spacers or camber adjustment. I only get a little rub at full turn. The diameter will keep your speedo right on target as well whereas 245s will be ~1mph off @60mph.

[tawhid]

Hey thanks for your message! do you have xdrive?

[tawhid]

Also, I read it depends on the tire brand as well. Are you using Michelin?

[Dagstar]

Originally Posted by tawhid

Hey thanks for your message! do you have xdrive?

Yup xdrive, the F31 (wagon) only came AWD in the US. I'm on Continental ExtremeContact Sports, which I believe run a bit wider than the Michelins (PS4S I'm assuming).

[nh90crxsi]

I’m running ET 30 18x9 ARC8 with DWS 06 plus in 255/40-18 with no issues

[mobbinthesteez]

Originally Posted by nh90crxsi

I’m running ET 30 18x9 ARC8 with DWS 06 plus in 255/40-18 with no issues

Do you have any pictures? I am wanting to do this exact setup on my 440i. Thanks!

[visionaut]

Either works. I run 255/35s all around on my summers (Apex SM-10s in 19x9 et30) and 245/40s all around on my winters (18x8 et29 Sparcos).

If you’re considering the 255 square setup for winter, realize it’s a tighter fit once snow packs up in the wheel well, and you’ll get more spray on the side of the car... (9” et30 width wheels poke a bit in front). The 245s are 8mm less diameter, so less than 1 mph higher speedo reading at 60mph.