Help me figure out wheel setup

I'm running 275/30's in the rear. Stock is 265/35's, I believe. Sorry, don't have the original specs handy. I have no problems at all. I went down in aspect with the wider width to compensate for it. They are mighty skinny. Mine are pushed almost all the way to the edge of the wheel well. But I did not change my offset, for fear of voiding any warranties. I would worry that 285's would sling too much debris against the paint and mar your finish. I have had no issues with this setup. I am not sure about a 40 aspect on that wide of a tire when you are on low. That could be a problem.

I tend to be conservative about this after years of pushing the limit. But I am getting older!

Hi,
I have a P85+ with the staggered setup. 265rear/245 front on 21s. A 285 on the rear would have to be hitting something in the suspension. Unless the rims you describe change the tire profile. Not sure. With a rear wheel drive I need all the rubber I can get on the rear. But you have a AWD. You could square it off for tire rotation. But maybe you are going for a look. Either way, I can vouch for the Michelin Pilot Sports as an incredible performance tire on the MS. Not sure why you are picking what you did. But go for what you want. It is all good. Range is effected by tire "stickiness" where width can be part of that equation. But it is mainly tire compound.

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@CHG-ON
You and I picked up our P85+s on the same day. Perhaps you got yours at the Fremont factory, too. We are unique in that they only started putting AutoPilot in the MS the last week of Sept. 2014. To have a P85+ with AutoPilot is unique. BTW I just kept the P85+ Staggered wheel tire set up. I love those Michelin Pilot Sports!

I'm running stagger 245//35 21*9.0 and 285/30 21*10.5, car is lowered with no finger gap between the fender and wheels, minor rubbing when carry passenger going through bumpy road, hope this gives you a guideline.

@vitaliy as much as you want to run a thicker 285/40 profile in the rear, your rolling diameter will be 29".

The factory rolling diameter on a 19x8" factory wheel is about 27.7" on a 245/45-19 tire.
Respectively the 21" Michelin performance setup for a MS is a 245/35-21" front, 265/35-21" rear. 27.8" front, 28.3" rear respectively.

You're going to be a tad bit bigger in overall diameter in the rear (which may be great to cover up all that gap in the standard suspension), but still running a little larger than you should be.

Also, the offset seems like it's built for a lowered vehicle, not a stock one with standard air suspension. In other words, the rear wheel(s) may appear to stick out on a MS that is not lowered.

vitaliy said:

Thanks for all the answers!
I'm looking at Goodyear Eagle RS-A EMT for the rears because there aren't many tires of that size (285/40/20)... Tire width pick of 285 is based on feedback from rims owner who claims that 275 look too stretched and offer no protection against curb rash. Tire offset of 40 is because I'm trying to find a compromise between comfort and look... Many more tires with 35 though, so I'm not sure.

I have standard (not air) suspension, so that should help.

Click to expand...

To be specific, we wouldn't mount a 20x10.5 with a 285/40-20" tire on a Model S.
You will gain more comfort with a thicker profile 40 tire on a 20" vs 35 profile on a 21".
We wouldn't mix and match tire models / brands.
We can't speak to rim protection.

We'd recommend you search for a 20x90 20x10 wheel setup with a 245/40-20 front tire and a 275/40-20 rear tire. With this setup you have many types of tires to choose from (ultra high performance, all season and winter tires).

PS: We will be manufacturing our TST in a 20x90 20x10 setup which fill fit BOTH the Model S and X. Our 20" will be load rated for a Model X as well.

Agree with the 9/10 in 20"
I had PSS 285 XLs on 19" and they were a bit tall. Today I ran a set of RE-71R's 245/275 19" in Autocross Enduro...crazy badass tires..gooey and they will not last! but sooo much fun, cornering at ~1.2 g's....beat my competition ('14 M3) by 3 seconds finally!! (on the same tires) kind of wish some 18"s would work :frown: