Michelin PS4S on 20" 2019 wheels

[LandToSea]

I see a lot of comments about the 235 sizing being undersized for the 9" Uber wheels. Does the same apply to the older style 20" wheels on my M3P? I am not sure of their width. If yes, what size should we be replacing with 245/35?

 

[tm1v2]

The older M3P wheels were 20x8.5". So either 245 or 235 is a recommended width. And either 245/35R20 or 235/35R20 will fit just fine overall (in terms of fitting the car not just the wheel).

I've read (no personal experience!) that the Tesla-spec 235/35R20 PS4S is "better" in some ways than regular PS4S in that size, with wider tread than most 235 width tires, and that there's little point in getting 245/35R20 for the PS4S if you can get the Tesla spec 235/35R20 instead. (Again this is just something I've read here from owners of older M3P, not personal experience.)

However if getting a different tire, or the Tesla spec PS4S isn't available anymore, then personally I'd go for 245/35R20. I've always used 245 width on 8.5" wide wheels, I'd rather have the extra width than not, and on this car I'd rather have that extra bit of diameter too.

I'm using 245/45R18 on 18x8.5" wheels on my 2021 M3P, for what that's worth. My older Tesla came with 245 on 8.5" wide, and so did my last ICE car.