What gain in Range will I get by shaving 6-7 pounds off the 20'' OEM

[desiringbroom]

Hello Folks,

I am really debating as if I should spend that crazy money toward a new set of 20'' Aftermarket wheels in order to replace the oem M3P 20''. I know the oem are around 28lbs each and I have seen some 20's aftermarket going at around 21-22. My only concern at this point is the range improvement and not considering other factors. Will be using the same tires. Anyone can chime in with personnal data or complex math calculations

Thanks

 

[GWord]

Depends on the kind of driving you are doing. Acceleration and driving dynamics benefit from less unsprung mass, especially less moment of inertia, leading to better stop and go efficiency. Better wheel aerodynamics help with high speed cruising efficiency. That's why you see hyper efficient cars with pizza cutter looking wheels.

 

[jerry33]

Basically, the answer is "not much", although how "not much" depends upon the amount of start and stop driving you do. The reason for "not much" is that the wheels are closer to the centre of rotation than the tires are, so they have less effect. (The belts and tread of the tire have a much greater effect).

 

[Zcd1]

Answer is “zero” extra range. Don’t buy new wheels of the same size expecting extra range.

 

[pnlyee]

The gains will be very minimal as others have suggested. Below is a link to another post which details my data.

Performance not getting 310 miles promised

 

[KenC]

I'd be concerned about durability of such ultra-light wheels.

 

[Nocturnal]

Answer is “zero” extra range. Don’t buy new wheels of the same size expecting extra range.

Definitely not zero, but won't be anywhere near enough to pay off.

Saving 7 pounds per wheel will result in a small performance improvement. I can't remember the rule of thumb but rotating weight reductions are worth more than static weight. Might see .1 second or .05 second improvement in 1/4 for example.

 

[jerry33]

Definitely not zero, but won't be anywhere near enough to pay off.

Saving 7 pounds per wheel will result in a small performance improvement. I can't remember the rule of thumb but rotating weight reductions are worth more than static weight. Might see .1 second or .05 second improvement in 1/4 for example.

That's correct, but it's referring to the wheel/tire assembly. The wheel would add only a small fraction of that.

 

[Zcd1]

Definitely not zero, but won't be anywhere near enough to pay off.

Saving 7 pounds per wheel will result in a small performance improvement. I can't remember the rule of thumb but rotating weight reductions are worth more than static weight. Might see .1 second or .05 second improvement in 1/4 for example.

The OP specifically asked about range improvement, and specifically said he/she wasn't interested in other factors...

Range will not be measurably affected by changing from one 20" rim to another 20" rim, regardless of weight savings.

 

[Nocturnal]

The OP specifically asked about range improvement, and specifically said he/she wasn't interested in other factors...

Range will not be measurably affected by changing from one 20" rim to another 20" rim, regardless of weight savings.

Yes it will. Decrease weight and range will increase. It's physics. Add 200 lbs to your trunk and see what happens to your range.

 

[nvx1977]

Yes it will. Decrease weight and range will increase. It's physics. Add 200 lbs to your trunk and see what happens to your range.

and if he's subtracting 200 lb off his wheels, he might notice a change in range too.

 

[Nocturnal]

and if he's subtracting 200 lb off his wheels, he might notice a change in range too.

I didn't say it would be a large change. "Not zero".

 

[IraB]

I would agree that there will be a very small increase in range, probably not sufficient to measure compared to temperature effects. The main improvement would be in the areas of braking, transient cornering (i.e., quick direction changes), and acceleration. I have swapped heavy wheels for lighter performance wheels on numerous ICE cars and weight reductions from 5 lbs per wheel and up (on 18" and 19" wheels) produce very noticeable results.

As for durability, as long as the light wheels are quality forged, they will be substantially stronger than the factory cast wheels. Of course, that is why these new wheels are crazy expensive.

 

[AlanSubie4Life]

Hello Folks,

I am really debating as if I should spend that crazy money toward a new set of 20'' Aftermarket wheels in order to replace the oem M3P 20''. I know the oem are around 28lbs each and I have seen some 20's aftermarket going at around 21-22. My only concern at this point is the range improvement and not considering other factors. Will be using the same tires. Anyone can chime in with personnal data or complex math calculations

Thanks

I think for RANGE, you will likely hurt your range by going to a different 20" wheel. The Tesla 19" and 20" wheels are likely designed with SOME considerations for aerodynamic efficiency. Changing to a different spoke design may well be detrimental at highway speeds. If you change to something very very similar, it's possible that you will have a minuscule improvement in range due to the weight difference.

When you are at a steady-state speed, the rotational kinetic energy of your wheels does not change. So for highway range, while you'll have to put a little less into the wheels to get them spinning, once they are at that speed, there is no further savings. And furthermore, when you slow down, there will be slightly less energy to reclaim (since the spinning wheels are lighter). There IS savings from that reduced "slosh" of energy, but you could imagine that it would be very small if your speed is fairly constant.

I think your primary consideration when going to a new set of wheels for range (the most typical case for range would be a long freeway run - not stop-and-go driving) is to consider the aerodynamic properties of the wheel design, not the weight.

Since you're staying with exactly the same tires we don't need to discuss the impact of tires.

 

[Zcd1]

I think for RANGE, you will likely hurt your range by going to a different 20" wheel. The Tesla 19" and 20" wheels are likely designed with SOME considerations for aerodynamic efficiency. Changing to a different spoke design may well be detrimental at highway speeds. If you change to something very very similar, it's possible that you will have a minuscule improvement in range due to the weight difference.

When you are at a steady-state speed, the rotational kinetic energy of your wheels does not change. So for highway range, while you'll have to put a little less into the wheels to get them spinning, once they are at that speed, there is no further savings. And furthermore, when you slow down, there will be slightly less energy to reclaim (since the spinning wheels are lighter). There IS savings from that reduced "slosh" of energy, but you could imagine that it would be very small if your speed is fairly constant.

I think your primary consideration when going to a new set of wheels for range (the most typical case for range would be a long freeway run - not stop-and-go driving) is to consider the aerodynamic properties of the wheel design, not the weight.

Since you're staying with exactly the same tires we don't need to discuss the impact of tires.

Thank you for being willing to write what I wasn't willing to take the time to write...

Bottom line: ZERO extra range.

 

[MagnusMako]

I'd be concerned about durability of such ultra-light wheels.

If he goes with good rotary forged ones, he'll be fine.

 

[lolder]

That amount of weight saving will be un-measureable in a 4500 lb car.

 

[Xenoilphobe]

Hello Folks,

I am really debating as if I should spend that crazy money toward a new set of 20'' Aftermarket wheels in order to replace the oem M3P 20''. I know the oem are around 28lbs each and I have seen some 20's aftermarket going at around 21-22. My only concern at this point is the range improvement and not considering other factors. Will be using the same tires. Anyone can chime in with personnal data or complex math calculations

Thanks

Go with 18 inch mono block forged. you will never recoup the cost, but they will be far more durable, have a broader selection of tires and most likely never crack a wheel. and the tires will be much cheaper to replace...

 

[Xenoilphobe]

Here is an option they make 18 ($2K), 19 ($2.7K) and 20 staggered ($3.2K) specifically for the Model 3
T-S5 Forged Split 5 Spoke Wheel

 

[N54TT]

There are several factors with regards to wheels that will effect efficiency. Weight, design and specs(width/offset). If you found a 20” wheel that weighs 21-22lbs, has same design as stock and same width/offset....I’m sure there would be a noticeable difference. But most of the aftermarket wheels have an open wheel design....which doesn’t help efficiency. That being said. For what it’s worth...my experience running staggered and higher offset 20” VS08’s is that I get the same if not slightly better wh/mile than the stock 20’s.

I'd be concerned about durability of such ultra-light wheels.

For a wheel to be that light, they’re most likely fully forged wheels (Ie forged monoblock) and durability shouldn’t be an issue.