[rommeeeezy]

Hi everyone,

Just got into my new to me 2020 X3M. I love the car so far, but I’ve experienced this in the past with my f80 M3, where the stock wheel and tire combo on the competitions is much harsher due to the thin sidewall.

What is the thickest sidewall I can put on a 20” wheel that won’t rub. I’m not looking at getting winter tires as I’m in Central CA and winters are mild and a PS4S is perfectly fine especially with AWD.

Any ideas? I’ve seen maybe a 255/45/20 and a 285/40/20? But not sure if that will retain similar turn in, or if I should stick with the same 255 fronts and 265 rears.

Thanks

[thestimp]

Search the forums before the boomers come get you. 265/40/21 295/35/21 for 21" I suspect something similar for 20's. dozens of posts you can sift through.

[SearsTurnSix]

I'm in a similar bind, and so this is a HOT topic I have been actively researching. My X3MC order is currently equipped with 21" wheels that will receive UHP summer tires, hopefully PS4S (what I've always run on my GTI). If I want to take it up to the snow I will need a second wheel-set with Winter or All Seasons.

Incidentally, I've driven my GTI up in Tahoe in snow/ice with PS4S (not during a storm). It's doable if you drive, VERY slowly and chain-up during storms. The PS4S is down-right DANGEROUS on snow/ice in cold temperatures.

I've been back and forth between 20" and 21" wheels, considering ride comfort and occasional snow performance. I'm all but convinced that 20" wheels will not transform the car into a plush ride (unfortunately). Rather, I think the argument for 20" is to run a single wheel set with UHP All Seasons. Some numbers:

20" X3M 764M
Front: 255/45-20, 9Jx20
Rear: 265/45-20, 10Jx20
Factory tires: MICHELIN Pilot Sport 4 SUV?
New wheelset: $4678 (more expensive than 21"?)

BTW: There isn't a convenient sizing for Michelin PS4S on the 20" wheels. Unfortunately, they are not offered in 45-series in 20x9 and 20x10 wheels. Unfortunately, you'll need to run non-standard tires to maintain rolling diameters.

21" X3MC 892M
Front: 255/40-21, 9.5Jx21
Rear: 265/40-21, 10Jx21
New wheelset: $3845
Factory tires: Michelin PS4S* or Conti Sport Contact 6*

An alternative I'm considering is non-Comp on 20" wheels and to run snow/winter capable UHP All Seasons, like the PS All Season 4 once the OEMs die.
Front: MICHELIN Pilot Sport All Season 4 - 255/45ZR20/XL 105Y XL BSW
Rear: MICHELIN Pilot Sport All Season 4 - 265/45ZR20/XL 108Y XL BSW

This is a highly regarded tire that truly can work in all weathers. It’s actually the standard tire on the C8 Stingray. Need to remember the X3M is an SUV. Running non-UHP summers on it shouldn't be out of place or ruin-it.
https://www.tirerack.com/tires/tires...=835YR8PSAS4XL

[rommeeeezy]

Originally Posted by thestimp

Search the forums before the boomers come get you. 265/40/21 295/35/21 for 21" I suspect something similar for 20's. dozens of posts you can sift through.

Yeah, I saw this. I don’t think this increases any sidewall aside from the front by a smidge.

I’m wondering there’s any good 20inch wheel and tire combo’s since that’s the smallest wheel where you can clear the brakes and put on a 45 series tire to get more sidewall. I just wanted to know if people were running like a 265/45/20 and 295/40/20 tire or whatever other tire permutations.

[SearsTurnSix]

Originally Posted by rommeeeezy

I just wanted to know if people were running like a 265/45/20 and 295/40/20 tire or whatever other tire permutations.

Front: 255/45-20
Rear: 265/45-20

See the above. Run the same width tires as the 21" but 45-series on 20" wheels. The difference in side wall height is only 13mm, or 0.5".