# 0-60, Skidpad grip and Braking - 18" vs 19" wheels



## RAS550 (Jul 28, 2018)

I placed an order for the dual motor with 18 inch wheels last week, and then saw the Edmunds track tests comparing the 18" and 19" packages. According to them, the 19 inch wheels/tires are better in following ways:
1) Skidpad improves from 0.85g to 0.93 g, which is HUGE imo.
2) 0-60 improves by 0.2 S - not too bad based on just tires and wheels
3) Finally, stopping distance improved from 133ft to 128 ft. Neither is great but I'll take the lower number.

My theory is that the improvements are not due to wheel size but the tire compound. While both are all season, the 18" are low rolling resistance which seems to be holding them back.

Now here's the dilemma I face:
a) Switch my config from 18" to 19" while I am still able to (next couple of days)
b) Be happy with the 18" for now. When its time to replace tires, get 18" ultra high performance all seasons instead of grand touring all season. This should show even better grip and braking than the standard 19" wheels+tires.

What do you guys think? Insights from people who have switched to ultra high performance or extreme performance tires would be very helpful?

Link for the Edmunds review -


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## MelindaV (Apr 2, 2016)

someone like @Mad Hungarian may have info differences between the Conti and Michelin tires, but my impression is the Continental would be the better between the two for performance.

ETA; my opinion is totally based on currently owning a different continental tire that I really like


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## garsh (Apr 4, 2016)

RAS550 said:


> Now here's the dilemma I face:
> a) Switch my config from 18" to 19" while I am still able to (next couple of days)
> b) Be happy with the 18" for now. When its time to replace tires, get 18" ultra high performance all seasons instead of grand touring all season. This should show even better grip and braking than the standard 19" wheels+tires.[/MEDIA]


c) Keep the 18s. Buy replacement tires immediately. Sell the OEM tires on craigslist.
d) Keep the 18s. Buy aftermarket 19s. Sell the 18 wheel/tire set on craigslist.


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## RAS550 (Jul 28, 2018)

MelindaV said:


> someone like @Mad Hungarian may have info differences between the Conti and Michelin tires, but my impression is the Continental would be the better between the two for performance.


MelindaV - that's correct for the tires from the factory, because of the specific ratings for these two tires. In general both Conti and Michelin are two of the best tire brands and similar rated tires (e.g. ultra high performance summer) would have similar braking performance and grip.


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## RAS550 (Jul 28, 2018)

I like options c and d! However I do think its a hassle to sell on CL so I may end up keeping the ones I configure with until they are bald.

I have a test drive scheduled for Wednesday. Let me see which tire I get to test drive and how it feels, and I'll decide based on that.


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## John (Apr 16, 2016)

Yeah, supposedly it's the grip of the tires, not the size of the wheel.


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## garsh (Apr 4, 2016)

John said:


> Yeah, supposedly it's the grip of the tires, not the size of the wheel.


When I changed my Leaf from the OEM low-rolling-resistance Ecopias to some random tires I bought off of Craigslist (Capitol brand), it made a HUGE difference in cornering ability. I paid for it with 10-20% range loss, but it was worth it for a couple of years until battery degradation became too bad.


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## garsh (Apr 4, 2016)

RAS550 said:


> I like options c and d! However I do think its a hassle to sell on CL


You can also sell on ebay, or list them forsale on this website or another Tesla forum (to avoid the ebay fees). Shipping a tire or wheel/tire combo actually isn't all _that_ expensive if you use Fedex Ground. Packaging for shipment isn't too bad - add padding and then cardboard over the wheel cover, throw the wheel/tire into a garbage bag, then wrap the whole thing completely in packing tape.


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## Mad Hungarian (May 20, 2016)

MelindaV said:


> someone like @Mad Hungarian may have info differences between the Conti and Michelin tires, but my impression is the Continental would be the better between the two for performance.


Neither of the OE tires is performance-focused although both have some ability in their basic DNA, I mean even a base Model 3 has to have handling cred. But both the Primacy MXM4 and the ProContact RX are essentially Grand Touring tires with an extra helping of low rolling resistance thrown in. I suspect if we were to compare them in identical sizes there wouldn't be much to separate them. The main reason the 19" Conti does so much better in cornering tests is because of its shorter, firmer sidewall. If you were however to fit a no-holds-barred true performance tire to the 18" wheels I am certain they'd walk all over the 19" OE setup.

The only reason I'd go with the OE 19" option is if you really like the Sport wheel's design. Otherwise I'd stick with the 18" and upgrade the tires at some point, or if it's really just a matter of liking how the bigger diameter looks stick with the 18" config and use the money saved to buy the perfect 19" package, then swap back and forth depending on how you're using the car.

Or if the goal is really just to get max performance for minimum cost, keep the Aero wheels and move up to a 255/40R18 in a serious performance tire. That would give you some fierce grip and you'd still have the option to use the covers for long trips to negate some of the added resistance for travelling.


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## MelindaV (Apr 2, 2016)

Mad Hungarian said:


> Neither of the OE tires is performance-focused although both have some ability in their basic DNA, I mean even a base Model 3 has to have handling cred. But both the Primacy MXM4 and the ProContact RX are essentially Grand Touring tires with an extra helping of low rolling resistance thrown in. I suspect if we were to compare them in identical sizes there wouldn't be much to separate them. The main reason the 19" Conti does so much better in cornering tests is because of its shorter, firmer sidewall. If you were however to fit a no-holds-barred true performance tire to the 18" wheels I am certain they'd walk all over the 19" OE setup.
> 
> The only reason I'd go with the OE 19" option is if you really like the Sport wheel's design. Otherwise I'd stick with the 18" and upgrade the tires at some point, or if it's really just a matter of liking how the bigger diameter looks stick with the 18" config and use the money saved to buy the perfect 19" package, then swap back and forth depending on how you're using the car.
> 
> Or if the goal is really just to get max performance for minimum cost, keep the Aero wheels and move up to a 255/40R18 in a serious performance tire. That would give you some fierce grip and you'd still have the option to use the covers for long trips to negate some of the added resistance for travelling.


I went back and added a disclaimer to my earlier post, explaining that my reasoning was purely based on my current Continental tires that I really like  (which are one of their performance tires). Once I wear thru the stock 19" tires, I will very likely upgrade to a sportier tire. But in the meantime, having watched the Edmonds video the OP included, I think I'll be happy with the stock Continentals


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## Mad Hungarian (May 20, 2016)

MelindaV said:


> I went back and added a disclaimer to my earlier post, explaining that my reasoning was purely based on my current Continental tires that I really like  (which are one of their performance tires). Once I wear thru the stock 19" tires, I will very likely upgrade to a sportier tire. But in the meantime, having watched the Edmonds video the OP included, I think I'll be happy with the stock Continentals


Oh no need to explain or amend... Conti makes a wide range of exceptional tires for all sorts of applications, it's not for nothing that they supply something like 20% of all the world's OEM tires.


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## MelindaV (Apr 2, 2016)

Mad Hungarian said:


> Oh no need to explain or amend... Conti makes a wide range of exceptional tires for all sorts of applications, it's not for nothing that they supply something like 20% of all the world's OEM tires.


I honestly think my love for my current tires has more to do with the stock Eagle1 tires they were replacing (which I think were the worst of any I've had on a car) than the Continentals themselves.


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## PNWmisty (Aug 19, 2017)

Mad Hungarian said:


> But both the Primacy MXM4 and the ProContact RX are essentially Grand Touring tires with an extra helping of low rolling resistance thrown in. I suspect if we were to compare them in identical sizes there wouldn't be much to separate them.


The primary difference in the ratings of the OEM tires is the treadwear rating (the 18" have higher treadwear rating). Probably due to a grippier rubber compound on the 19". I'm guessing this explains much of the difference in stopping ability, acceleration and skid pad results.

Neither tire has a particularly sticky rubber compound, at least by modern standards, and therefore have limited ability to reach adhesion levels that would benefit much from profiles lower than the 18" already has. In other words, the sidewall profile of both the 18" and 19" are likely well matched to the grip of each compound.


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## Mad Hungarian (May 20, 2016)

PNWmisty said:


> The primary difference in the ratings of the OEM tires is the treadwear rating (the 18" have higher treadwear rating). Probably due to a grippier rubber compound on the 19". I'm guessing this explains much of the difference in stopping ability, acceleration and skid pad results.
> 
> Neither tire has a particularly sticky rubber compound, at least by modern standards, and therefore have limited ability to reach adhesion levels that would benefit much from profiles lower than the 18" already has. In other words, the sidewall profile of both the 18" and 19" are likely well matched to the grip of each compound.


Mmmm, in theory correct but I am always loathe to make any assumptions about performance based on treadwear numbers unless there's a really dramatic difference, and even then only when we are talking about Tier 1 / Tier 2 manufacturers. The problem is that the UTQG ratings are not assigned by an independent agency in the U.S., the tire manufacturers perform their own testing. So generally I am cautious about comparing brand X's result to brand Y's.
Another problem about making such assumptions is we don't always know why one tire gets a lower/higher TW rating, so many variables at work in the pattern and exact compound choices... company X may live with a 20% lower number not because they formulated the tire for higher performance levels on dry surface but because they wanted better flexibility/grip in low temps.
Only real way to know performance differences is a straight up set of tests in the identical size.
In fact it would be quite interesting to turn the tables on this scenario and see what happens if we were to run the same set of tests with the lower profile 20" Michelin Pilot Sport 4S tires in the PUP package and their 500 rating against the taller 19" Contis with their 400.


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## PNWmisty (Aug 19, 2017)

Mad Hungarian said:


> Only real way to know performance differences is a straight up set of tests in the identical size.


True. Tires of different sizes are not the same tires! Sometimes even the belt arrangement/number of plies/etc. is different.

However, in tests that I've seen published of the same model tire in different profiles, simply going to a lower profile had, at best, a marginal improvement in the metrics of braking, accelerating, and cornering g's and sometimes a slightly negative effect (as the profile became overly low-profile). There is a sweet zone for every tire/car and profiles near the sweet zone do not have dramatically different results but going lower than the sweet zone decreases performance.



> In fact it would be quite interesting to turn the tables on this scenario and see what happens if we were to run the same set of tests with the lower profile 20" Michelin Pilot Sport 4S tires in the PUP package and their 500 rating against the taller 19" Contis with their 400.


I see your point here, that treadwear indicator is not a good predictor of grip. And I agree. But I do think the OEM 19's extra grip is primarily a function of the compound, not so much the lower profile.


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## Mad Hungarian (May 20, 2016)

PNWmisty said:


> True. Tires of different sizes are not the same tires! Sometimes even the belt arrangement/number of plies/etc. is different.
> 
> However, in tests that I've seen published of the same model tire in different profiles, simply going to a lower profile had, at best, a marginal improvement in the metrics of braking, accelerating, and cornering g's and sometimes a slightly negative effect (as the profile became overly low-profile). There is a sweet zone for every tire/car and profiles near the sweet zone do not have dramatically different results but going lower than the sweet zone decreases performance.
> 
> I see your point here, that treadwear indicator is not a good predictor of grip. And I agree. But I do think the OEM 19's extra grip is primarily a function of the compound, not so much the lower profile.


It is for sure a complex matter and one I always enjoy debating, always so much to discuss/learn.
One of the most interesting tests I've seen on the plus-size effects was the one Car and Driver ran back in 2010. Unfortunately it isn't 100% applicable to our discussion here as they not only changed profile but also increased section width as they stepped up diameter. But to your point it clearly isn't an endless series of improvements, the Golf seemed to max out performance at 225/40R18. Also a nice illustration of how energy consumption goes up in a relatively linear fashion as one goes wider and heavier.


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## John (Apr 16, 2016)

Mad Hungarian said:


> Neither of the OE tires is performance-focused although both have some ability in their basic DNA, I mean even a base Model 3 has to have handling cred. But both the Primacy MXM4 and the ProContact RX are essentially Grand Touring tires with an extra helping of low rolling resistance thrown in. I suspect if we were to compare them in identical sizes there wouldn't be much to separate them. The main reason the 19" Conti does so much better in cornering tests is because of its shorter, firmer sidewall. If you were however to fit a no-holds-barred true performance tire to the 18" wheels I am certain they'd walk all over the 19" OE setup.
> 
> The only reason I'd go with the OE 19" option is if you really like the Sport wheel's design. Otherwise I'd stick with the 18" and upgrade the tires at some point, or if it's really just a matter of liking how the bigger diameter looks stick with the 18" config and use the money saved to buy the perfect 19" package, then swap back and forth depending on how you're using the car.
> 
> Or if the goal is really just to get max performance for minimum cost, keep the Aero wheels and move up to a 255/40R18 in a serious performance tire. That would give you some fierce grip and you'd still have the option to use the covers for long trips to negate some of the added resistance for travelling.


Wouldn't larger wheels give you more flexibility on brake upgrades?


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## Mad Hungarian (May 20, 2016)

John said:


> Wouldn't larger wheels give you more flexibility on brake upgrades?


Oh for sure, but that as that wasn't on @RAS550 's original laundry list I didn't take it into account.
Truth be told though you can still easily fit up to a 355 mm rotor under the 18" wheel and that would still be a pretty significant upgrade.


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