265/40/18 on the aero wheels? Anybody have a pic?

lemketron

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#22
I strongly considered, but didn't want to go with the 255 options. The 255 40 is smaller outside diameter, and the 255 45 was larger and had a significantly higher rotational moment of inertia compared to stock (based on simplified calculations).
I assume that means it would negatively impact acceleration?

I'm considering the 245/45 Michelin PS4S. It's only about 1.5% larger (+1mph at 65mph) vs 2.7% for the 255/45, so I'm hoping that any impact on performance (or range) would be minimal...?
 

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#23
I assume that means it would negatively impact acceleration?

I'm considering the 245/45 Michelin PS4S. It's only about 1.5% larger (+1mph at 65mph) vs 2.7% for the 255/45, so I'm hoping that any impact on performance (or range) would be minimal...?
Yes, a heavier and/or taller tire will use more energy and could be slower accelerating because of it, though the friction characteristcs of the tire on a specific surface also matter for acceleration in any given direction.

A bigger issue may be that performance oriented tires like the 4S may be less efficient than the Primacy due to design differences. The latter is designed to use less energy. The latter is designed to stick better. So be aware that there is a tradeoff between range and performance when choosing different types of tires. This is reflected in the range/energy results for the different factory tires/wheels in Model 3.
 

lemketron

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#24
A bigger issue may be that performance oriented tires like the 4S may be less efficient than the Primacy due to design differences. The latter is designed to use less energy. The latter is designed to stick better. So be aware that there is a tradeoff between range and performance when choosing different types of tires. This is reflected in the range/energy results for the different factory tires/wheels in Model 3.
Absolutely. The tricky part is just not knowing, and feeling like I can't be the first one to try it (though admittedly there probably aren't that many people who are both nearly finished with the OEM Primacy tires, and considering switching to the PS4S and especially in a larger size.

I went through this same struggle with a 2011 LEAF, replacing the Bridgestone Ecopias with stickier Michelins. It took a big hit on range but the 2011 LEAF didn't have much to begin with. When my wife took over that car we went back to Ecopias to improve the range.

However, now with the LR3RWD, I have 300+ miles of range, and aside from it being nice to be able to drive from the Bay Area to Santa Barbara without stopping, I can afford to give up a little range to see how the summer tires compare to the OEM A/S. Plus Michelin gives you 30 days satisfaction guarantee so if the new ones are really disappointing in some way, I can always go back to the Primacy (or maybe PS4S in the original size).

I just wish there was some way to get a better idea of what to expect up front... Otherwise, it's ~$1000 gamble, and takes a year or two to run them out before it's practical to try again.
 

JeffC

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#25
Absolutely. The tricky part is just not knowing, and feeling like I can't be the first one to try it (though admittedly there probably aren't that many people who are both nearly finished with the OEM Primacy tires, and considering switching to the PS4S and especially in a larger size.

I went through this same struggle with a 2011 LEAF, replacing the Bridgestone Ecopias with stickier Michelins. It took a big hit on range but the 2011 LEAF didn't have much to begin with. When my wife took over that car we went back to Ecopias to improve the range.

However, now with the LR3RWD, I have 300+ miles of range, and aside from it being nice to be able to drive from the Bay Area to Santa Barbara without stopping, I can afford to give up a little range to see how the summer tires compare to the OEM A/S. Plus Michelin gives you 30 days satisfaction guarantee so if the new ones are really disappointing in some way, I can always go back to the Primacy (or maybe PS4S in the original size).

I just wish there was some way to get a better idea of what to expect up front... Otherwise, it's ~$1000 gamble, and takes a year or two to run them out before it's practical to try again.
The Pilot Sport 4S is arguably the best street performance tire available today. No, it's not a soft compound track/race tire, but it has an excellent combination of feel, grip, predictablity, efficiency, etc. If you haven't tried it on a Model 3 Performance test drive, you're welcome to drive mine when the roads dry eventually. (My car is totally stock Performance Upgrade option currently.)

For a street tire, the 4S sticks like glue and also wears very well. The Primacy, not so much. But 99% of the time, I am not cornering or braking at 1g, and the performance tires are sort of a penalty for their lower efficiency. Of course it's nice to be able to push the car a little occasionally when there's no one around.

TBH I'd prefer the Aero wheels and Primacy tires for road trips if they would fit over the rear performance brakes, but they don't. Having say 5-10% better range/efficiency on road trips in particular is a sigificant benefit.

Consider getting a different set of aftermarket wheels to put the 4S on. That way you can also go wider if you like. (And of course note that wider tires also have lower efficiency due to slightly greater aerodynamic drag due to greater frontal area.) That said, the Aero wheel is a significant advantage for its low drag, so I can see the attraction of keeping it.
 
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#26
Hi folks, new member and about to be new owner of red/black LR AWD Model 3 arriving this Saturday !!!.

My current SCCA autocross car is 2010 Subaru STI, which has 18 x 8.5 rims. Over the last 9 years, I've run 265/35/18 Falken Azenis and Dunlop Starspec I, II, & IIs on those 8.5 wide rims all around with no issues. Looks good too. Just need to be careful picking wheel offset to maintain clearance with suspension strut/shock and fender lip.

While the section width of each tire brand/model is different, for a generic tire, 265 versus 235, it's only 9/16" wider on both inside & outside. If Model 3's have at least that much clearance plus a bit more to account for tire flex when cornering, it should be fine on stock rims. For my Model 3, I plan on using the STI's current 265/40/18 Azenis when I autocross it.

FYI - the last Washington DC Region SCCA event had three Model 3 running (1 Performance, 2 AWD); they ran well, competitive in their classes. The non-performance Model 3 is in the same class as the STI's and beat me by 1.5 seconds.

- Harry
 
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#27
Just had my autocross tires, 265/35/18 Falken Azenis I mentioned above, mounted on the stock 18" Aero rims. They fit fine, lots of clearance to front strut, gobs of room in the back.

On the street, the car handles better, with much better initial turn in and cornering & braking. W/Mile is up by 10 - 15%. Tire noise is definitely noticeable, mostly because of the camber wear from previous year's worth of autocrosses on those tires.

Autocrossed the Tesla on these tires last weekend, a lot more fun with sticky tires! Asked one of the nationally competitive drivers to take a run in the car - he was within 2/10 of winning the class, with no experience in the car and with 2nd tier tires (Azenis are not the best performance tires; RE-71R or Rivals are the top tier, about 1.5 sec faster on 60 sec course), so looks like the Model3 AWD will be very competitive in my class, as soon as I don't suck at driving.

Pix (think the wider tire looks better than stock):
 

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#28
Just had my autocross tires, 265/35/18 Falken Azenis I mentioned above, mounted on the stock 18" Aero rims. They fit fine, lots of clearance to front strut, gobs of room in the back.

On the street, the car handles better, with much better initial turn in and cornering & braking. W/Mile is up by 10 - 15%. Tire noise is definitely noticeable, mostly because of the camber wear from previous year's worth of autocrosses on those tires.

Autocrossed the Tesla on these tires last weekend, a lot more fun with sticky tires! Asked one of the nationally competitive drivers to take a run in the car - he was within 2/10 of winning the class, with no experience in the car and with 2nd tier tires (Azenis are not the best performance tires; RE-71R or Rivals are the top tier, about 1.5 sec faster on 60 sec course), so looks like the Model3 AWD will be very competitive in my class, as soon as I don't suck at driving.

Pix (think the wider tire looks better than stock):
Thanks for the info! I'm going to soon install 265/40/18 on factory aeros. I have 3mm and 5mm spacers just in case the front does not clear. Compared to your 265/35/18 tires, is there still room in the front for my 265/40/18 tires? Or will I need a spacer?