Refresh S doesn’t have oem 20”If going by overall diameter, that 20" size is fine - it matches the OEM 20" from Tesla.
If the vehicle is preprogrammed for a certain tire, even changing the tire (not the size) will cause the mileage display to be off. There will be a difference in range from summer to A/S tires due to compound.
Going from the OEM 21" to the Sportline 20" will have offsetting penalties. The narrower rear tires is more efficient. The lighter combo will be more efficient. The A/S compound will be more efficient, The wider front will be less efficient, To what extent this effects things in real life I do not know. My guess is not much. Maybe we are all overthinking this one. Maybe not.
The front 20" will register 1.5% slower and the rear 0.5% slower on the speedo. As tread wears on any tire, you will get variance. I have OEM tires but have had to replace a few. Also, each tire manufacturer's diameters vary for the same tire size rating. The 285 front will stick out both inward and outward 0.4". Should not be an issue. The rear will be same outward and 0.4" further from the suspension. Should be good for both.
Again, keep in mind that Tesla is releasing a 20" OEM version that is 285 in the front and 305 in the rear. The offsets are the same with the OEM 20 and sportline 20".
With all that being said, I am all for keeping things OEM, All things being equal, I do not want aftermarket anything, But in true Tesla fashion, they have to complicate my life and not have an A/S size for their OEM rears. So soon I will need to do something for the cold months coming. I am holding out hope that Michelin will come out with the the Sport 4 A/S soon in the rear.
They have 19” 21”
Change the tires diameter you change the gearing.