Informal Range Poll: Uncovered Aero vs. Sport

Which wheel/tire combo is most efficient overall?


  • Total voters
    41
  • Poll closed .

Rich M

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#1
So what do you think will provide the least rolling resistance and/or most range: 18" Aero wheels with no covers and Michelin MXM4 tires vs. 19" Sport wheels with ContiProContact tires. They look to be the same width, with the 18" tire being 45 series and the 19" being 40 series. Both look to be classified as Grand Touring.

My guess is that the Uncovered Aeros still win at all but high speeds. Of course without a Mythbusters budget, we'll never know. But this forum is built on speculation!
 

KarenRei

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#5
In general you'd expect the 18s without covers to have less resistance - but you can't say for sure without either testing or a good CFD setup, as the shape of the rims is different for both vehicles.
 
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4701

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#13
Rolling resistance for these two (if tire compound WOULD be the same) would be pretty much the same.
What is different is aerodynamic drag. Wheels ruin the airflow. Therefore range will drop at higher speeds.
Both wheels look not good, though 18" have more slippery tire sidewall, less spokes, and sit closer to brake disc edge.
19" on the other hand try to be turbine shaped. Though visually they are still far from slippery.
All Model 3's will have air curtain airflow around front wheels (inlets are right next to fog lights). That will help both versions.
 

Ken Voss

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#14
Here are the facts about wheel size vs performance. Performance is not related to the diameter of the rim, it is related to un-sprung weight. Un-sprung weight includes the suspension, breaks, wheels and tires. The rule of thumb is every pound of un-sprung weight is equivalent to 6 pounds of body mass. Stock 18” wheels (with Aero hubcaps) weigh 21.6 pounds, the 19” sport wheel weigh 29.5 pounds, that’s a difference of 7.9 pounds times 4 wheels = 31.6 pounds of un-sprung weight, when we multiply by 6 this is the equivalent of adding 189.6 pounds of weight to the car. If you think that this will not impact acceleration and range you are kidding yourselves. Add to that that the 19” rims require a lower profile tire which will decrease shock absorbing characteristics and give a stiffer ride plus they are more prone to sidewall issues from potholes.

The decision to go with 19” vs 18” is a decision to trade performance for appearance. It is definitely important that we love the way our car looks but do it understanding that you will be sacrificing acceleration speed, range and ride quality in exchange for the looks.

The 18” TST is advertised to weigh in at 26 pounds (I don’t believe there is one in production yet that can actually be verified) so from a performance perspective this is better that the 19” Tesla Sport wheel put still not as good as the stock Aero, the 18” TST would be the equivalent of adding 105 pounds of body mass, putting their performance somewhere between the stock 18” Aero’s and the 19’ sport wheels
 

garsh

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#15
Here are the facts about wheel size vs performance. Performance is not related to the diameter of the rim, it is related to un-sprung weight.
It's both. And more.
Here's a good video explaining the challenges of creating a wheel and tire that won't self-destruct at high speeds.
 

SoFlaModel3

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#16
Here are the facts about wheel size vs performance. Performance is not related to the diameter of the rim, it is related to un-sprung weight. Un-sprung weight includes the suspension, breaks, wheels and tires. The rule of thumb is every pound of un-sprung weight is equivalent to 6 pounds of body mass. Stock 18” wheels (with Aero hubcaps) weigh 21.6 pounds, the 19” sport wheel weigh 29.5 pounds, that’s a difference of 7.9 pounds times 4 wheels = 31.6 pounds of un-sprung weight, when we multiply by 6 this is the equivalent of adding 189.6 pounds of weight to the car. If you think that this will not impact acceleration and range you are kidding yourselves. Add to that that the 19” rims require a lower profile tire which will decrease shock absorbing characteristics and give a stiffer ride plus they are more prone to sidewall issues from potholes.

The decision to go with 19” vs 18” is a decision to trade performance for appearance. It is definitely important that we love the way our car looks but do it understanding that you will be sacrificing acceleration speed, range and ride quality in exchange for the looks.

The 18” TST is advertised to weigh in at 26 pounds (I don’t believe there is one in production yet that can actually be verified) so from a performance perspective this is better that the 19” Tesla Sport wheel put still not as good as the stock Aero, the 18” TST would be the equivalent of adding 105 pounds of body mass, putting their performance somewhere between the stock 18” Aero’s and the 19’ sport wheels
In your example of adding 189 pounds of body mass, my inclination is to say essentially it’s like saying 18” wheels and 2 passengers in the car versus 19” and 1 passenger.

To which I will ask the question... how many (if any) of us drive our cars to the edge to the point where we notice performance differences between driving alone and driving with a passenger?

So don’t get me wrong I’m not questioning the fact there performance with the 18s is better — I’m saying 99% of real world drivers wouldn’t notice the difference.
 

Rich M

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#18
I love efficiency, but I love corners, winding roads, and a firm ride too. Guess I'll stick with the 18s, enjoy wearing out the Michelins, then replace them with high performance tires down the road.
 

Ken Voss

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#20
In your example of adding 189 pounds of body mass, my inclination is to say essentially it’s like saying 18” wheels and 2 passengers in the car versus 19” and 1 passenger.

To which I will ask the question... how many (if any) of us drive our cars to the edge to the point where we notice performance differences between driving alone and driving with a passenger?

So don’t get me wrong I’m not questioning the fact there performance with the 18s is better — I’m saying 99% of real world drivers wouldn’t notice the difference.
I don't disagree with you. In the real world the difference between 0-60 in 4.8 seconds or 5.2 seconds probably doesn't make any difference to most people and a range difference of 310 miles or 290 miles probably doesn't make that much of a difference either.

The point of my post was for people who believe because Tesla charges an extra $1,500 for 19" wheels that they are "better" If you want to buy 19" sport wheels because they look cool, absolutely go for it. If you want to buy 19" sport wheels because you somehow feel they are a better wheel and will make your M3 perform better, you should understand the facts before being disappointed in the results.