19" versus 20" Summer Tires for M3P

[JSWE]

Given that I live in Wisconsin, I'm not yet sure if I will keep the stock, 20" Uberturbines on my M3P. Can someone advise whether it would make more sense to stick with 20" aftermarket wheels or go down to 19" aftermarket wheels for summer driving? I am planning on going with 19" wheels for winter, but am not sure what to do for summer.

 

[yerEVan]

From my understanding, 20’s don’t do well with potholes. However on my Y Perf I have the 21” Uber and honestly they seem fine with mild to moderate sized potholes.

 

[Lindenwood]

I suppose “potholes” has a relative definition, but I regularly drive on the roughest [paved] roads I’ve ever experienced and am surprisingly content with the factory 20s, even when lowered. Of course, I do try to avoid the huge speed bumps and wheel-swallowing canyons, but I am FAR less worried about ride quality and I heel integrity with my 20s than I was before so actually picked up the car.

 

[tm1v2]

20" wheels and tires are more expensive. Stock Tesla big wheels with rubberband tires are known to crack (happened to me) and bend over bad pavement. Some aftermarket wheels should be stronger, especially forged ones, though it's still tough on a wheel when there is very little tire sidewall.

There's no performance benefit to 20" wheels over smaller diameters. It's for looks. If you like the look and you're okay with the downsides then go for it! You have to know your roads and driving habits to know if they'll be practical for you or not.

(I put forged 18" wheels on our M3P. 18" is the smallest diameter where you can find wheels that clear the M3P PUP brakes. The roads we drive on, at the speeds we drive, would break the stock M3P 20" wheels. We learned that lesson with the similar 245/35R21 setup our S P85 came with.)

 

[jackmott]

There is in fact a small performance benefit to 20” wheels on a track, usually, assuming the tire of your choice comes in that size. But it is on the order of tenths of a second and just has no relevance even to the most irresponsible street driving. So yeah go with 19s, safer for the wheels cheaper for you.

 

[yerEVan]

20" wheels and tires are more expensive. Stock Tesla big wheels with rubberband tires are known to crack (happened to me) and bend over bad pavement. Some aftermarket wheels should be stronger, especially forged ones, though it's still tough on a wheel when there is very little tire sidewall.

There's no performance benefit to 20" wheels over smaller diameters. It's for looks. If you like the look and you're okay with the downsides then go for it! You have to know your roads and driving habits to know if they'll be practical for you or not.

(I put forged 18" wheels on our M3P. 18" is the smallest diameter where you can find wheels that clear the M3P PUP brakes. The roads we drive on, at the speeds we drive, would break the stock M3P 20" wheels. We learned that lesson with the similar 245/35R21 setup our S P85 came with.)

This is sound advice. You may find a good market to sell the stock performance wheels and tires and pick up the more practical 18”.

My stealth P3D 2018 came with the 18” wheels and I ran 0-60 in 3.02s w/ 1ft rollout. 11.6 in 1/4 mile with all seasons.