dude, this is great info! I need to save it. Thank you!@Ital You can go slightly larger in diameter, but not 3% because of the front knuckle. Sizes up to 26.8" outer diameter are generally safe fits. In some tires you can go up to 27" diameter sizes but others will rub the front knuckle in those sizes. Especially allseasons from what I've seen here, probably due to their relatively tall tread compared to summer tires.
Sizes like 245/45R18, 245/40R19, and 245/35R20 fit reliably. Tesla's official Track Pack comes with 245/35R20 on 9" wide wheels. However 255/35R20 on 9" wheels for example is borderline, some tires fit in that size, and some rub (unless you are willing to shave them).
Stock Model 3 tire sizes and nominal diameters (the actual exact diameter of a specific tire model will vary!):
235/45R18 26.3" (18x8.5" aero wheels)
235/40R19 26.4" (19x8.5" sport wheels)
235/35R20 26.5" (20x9" or previously 20x8.5" M3P wheels - note the Uberturbines are 9" wide so on newer M3P the 235s are actually stretched and that probably shrinks the diameter slightly!)
I've been running 245/45R18 on 18x8.5" wheels on my M3P, first summer tires, now allseasons in the same size. No issues, fits great. The difference vs 235/45R18 is small of course, but the 10mm wider 245s give 3.2% extra width, 6.3% extra sidewall, and 1.1% extra diameter. Those are all good things for this car in my book, even if the differences are small. Either is a perfectly standard width for 8.5" wide wheels.
I doubt that I could feel much difference between 245 vs 235 in the same tire model (assuming both are XL rated and with equivalent inflation), but on paper I like everything about 245s more. Plus 245s were generally cheaper last time I was price comparing!
Did the wider tire affect your range?
I was thinking to keep the same width to be honest and go with a higher ratio, for example go from 235/45R/18 to 235/50R18, i am however considering new lighter wider wheels so I guess the wider tire would work better anyway I just want a more flush\aggressive offset, but I do not want to lose a lot of range. Thanks!