Anybody interested in a lighter weight Plaid?

[flyingfish28]

Hello everyone, I am new here and it will be my first Tesla.
I did a test drive with a 2023 Model S and found many things I loved and enough I hated that I am now sitting on the side line waiting for the fix to Tesla Vision.
If and when I buy, it will be an S Plaid (for the engineering prowess although the S Long Range was plenty fast enough).
One thing I like about the new S generation is the weight reduction. Wow!
I did not do an A/B comparison but it seems logical that the lighter cars should handle better. I am surprised this is not debated so much here?
And so, while waiting, I wondering about how to further reduce weight. I don't do track driving but I like a nimble car and we have lots of curvy roads where I live.
So far I have found the following possibilities:
- brakes
- wheels
Can anyone here with real world before/after experience give feedback on these mods? Does this make a significant/perceptible difference?
Vendors talk about unsuspended mass and rotational inertia. I get it but wonder whether such nuances will be perceptible given the car's weight?
And if you have other weight saving ideas...
Thanks

 

[Vorsteiner]

At Vorsteiner we offer a variety of weight reduction options for the Tesla Model S such as our carbon fiber hood.

 

[bkcyk]

Hello everyone, I am new here and it will be my first Tesla.
I did a test drive with a 2023 Model S and found many things I loved and enough I hated that I am now sitting on the side line waiting for the fix to Tesla Vision.
If and when I buy, it will be an S Plaid (for the engineering prowess although the S Long Range was plenty fast enough).
One thing I like about the new S generation is the weight reduction. Wow!
I did not do an A/B comparison but it seems logical that the lighter cars should handle better. I am surprised this is not debated so much here?
And so, while waiting, I wondering about how to further reduce weight. I don't do track driving but I like a nimble car and we have lots of curvy roads where I live.
So far I have found the following possibilities:
- brakes
- wheels
Can anyone here with real world before/after experience give feedback on these mods? Does this make a significant/perceptible difference?
Vendors talk about unsuspended mass and rotational inertia. I get it but wonder whether such nuances will be perceptible given the car's weight?
And if you have other weight saving ideas...
Thanks

Yea, I got one.

Pic below is my Track Pack MSP with 21" forged wheels that alone shaved 10lbs per corner. Do the math and it ends up being ~80-90lbs of total unsprung weight removed that cost me ~$26K USD.

Does the car drive appreciably better than stock to justify the spend? Yes, as there's a bit more alacrity behind the wheel for sure, but nothing that's going to enable my MSP to overtake a Lucid Sapphire running high 8s or feel better dynamically than a Taycan Turbo S. Don’t forget the Track Pack is a comprehensive hardware + software upgrade pkg to essentially make it a Plaid+. Does it brake tremendously better? Duh 100%, but it's still a 4600-700lbs sedan.

Once you gut the interior and start replacing glass with plastics to gut another ~100lbs of static weight to get to 4500-600lbs, you're crippling the Plaid as a superstar daily driver. It's already one of the lightest EVs, if not lightest, in its class.

I'm so pleased with my results.

Good luck!

 

[Speedr117]

@bkcyk, can you link to where you got your wheels, and the specs on them? Did you use the OEM tires and just swap out the rims, or did you go with a different size?

 

[bkcyk]

@bkcyk, can you link to where you got your wheels, and the specs on them? Did you use the OEM tires and just swap out the rims, or did you go with a different size?

Give Dave at Wheel Enhancement a ring (310) 836-8908. He knows my setup well and is an authorized dealer for many reputable wheel brands including non-China/Taiwan, motorsport vendors like Forgeline.

I'm all about sticking to factory specs as much as possible especially when it comes to specially formulated tires. I bought new OEM T2 tires and put the 3K mile young Arachnids with og rubber to bed so I can start fresh with a proper alignment done under my purview.

Zero vibes. Straight down the pike. Ninja silent. Good luck!

 

[flyingfish28]

I took a look at your web site. How much lighter is your carbon hood vs the aluminum part?
also FWIW I have collected from a very long thread here the following info:

Yea, I got one.

Pic below is my Track Pack MSP with 21" forged wheels that alone shaved 10lbs per corner. Do the math and it ends up being ~80-90lbs of total unsprung weight removed that cost me ~$26K USD.

View attachment 988644

Does the car drive appreciably better than stock to justify the spend? Yes, as there's a bit more alacrity behind the wheel for sure, but nothing that's going to enable my MSP to overtake a Lucid Sapphire running high 8s or feel better dynamically than a Taycan Turbo S. Don’t forget the Track Pack is a comprehensive hardware + software upgrade pkg to essentially make it a Plaid+. Does it brake tremendously better? Duh 100%, but it's still a 4600-700lbs sedan.

Once you gut the interior and start replacing glass with plastics to gut another ~100lbs of static weight to get to 4500-600lbs, you're crippling the Plaid as a superstar daily driver. It's already one of the lightest EVs, if not lightest, in its class.

I'm so pleased with my results.

Good luck!

Your car looks awesome., but I'd be scared of even leaving the center line for fear of scratching anything! Thanks for the report. I was of course not even thinking of replacing glass with plastic but maybe some mechanical parts?

 

[SilverGS]

Hello everyone, I am new here and it will be my first Tesla.
I did a test drive with a 2023 Model S and found many things I loved and enough I hated that I am now sitting on the side line waiting for the fix to Tesla Vision.
If and when I buy, it will be an S Plaid (for the engineering prowess although the S Long Range was plenty fast enough).
One thing I like about the new S generation is the weight reduction. Wow!
I did not do an A/B comparison but it seems logical that the lighter cars should handle better. I am surprised this is not debated so much here?
And so, while waiting, I wondering about how to further reduce weight. I don't do track driving but I like a nimble car and we have lots of curvy roads where I live.
So far I have found the following possibilities:
- brakes
- wheels
Can anyone here with real world before/after experience give feedback on these mods? Does this make a significant/perceptible difference?
Vendors talk about unsuspended mass and rotational inertia. I get it but wonder whether such nuances will be perceptible given the car's weight?
And if you have other weight saving ideas...
Thanks

IMO, light and sporty is not yet in the cards for an EV. Batteries are heavy , they account for about 1000 lbs of the Model S's weight.

Swapping out wheels, tires, hood, etc is just getting on the diminishing returns train.

 

[flyingfish28]

How much lighter is your carbon fiber part than the stock hood?

 

[flyingfish28]

I am compiling a list of brake and wheel part weights in order to help make informed decisions with regards to weight saving options.
So far, I can share the following data.

Preamble: the unsprung mass of the 4 stock 19 inch wheels plus brakes EXCLUDING suspension parts is:
Tires: 120 lbs
Wheels : 116 lbs
Brake rotors: 98 lbs
Brake calipers and pads approx. 85 lbs
Total 420 lbs or 192 Kg
Make this a nice round 500 lbs with suspension parts for the sake of simplicity.

Now let us look at how we can reduce weight by upgrading the brakes:

1) Keeping factory 19 inch wheels and only replacing all 4 factory rotors with same size two piece steel rotors from one of the well known aftermarket suppliers will save 22 lbs / 10 Kg of unsprung mass.
2) The Tesla Track Pack brake rotors shave another 11 lbs / 5 Kg for a total of 33 lbs or 15 Kg. I could not find enough data to determine if the Track Pack calipers are lighter or heavier than stock. I guess same weight at best.
When looking at potential weight savings with Track Pack, we must consider that it is not possible to keep the 19 inch factory wheels and so we must account for the weight difference between these and the 20 or 21 inch wheels and tires, which are - well larger!
Track Pack wheels are marginally heavier (10 lbs total).
Only a handful of forged ultra light wheels will provide a meaningful weight saving on the wheel/tyre set versus the stock 19 inch.
Furthermore, any 21 inch wheel, regardless of its manufacturing process will have a lot of mass located in the (larger) barrel which, resulting in a larger polar moment. So some of the weight savings (if any) will be lost in terms of rotational inertia due to this.
3) As an alternative to solution 1, one could install same size Carbon Ceramic brake rotors from RacingBrakes.
The unsprung weight savings are a whopping 50.2 lbs or 22.6 Kg but there is a catch: the cost. Parts alone are above 10 K USD.

So long story short: if you want to keep the 19 inch wheels, it is possible to save 50 lbs / 22 Kg on the brakes for 12 K USD installed and half of that for 4 K USD installed. This is roughly 10% or 5% of the unsprung mass.

I hope this was useful. Let me know if you'd like more comparisons and please provide data if you have any that would be relevant (for example caliper weights). Thanks

 

[W Cole]

I am compiling a list of brake and wheel part weights in order to help make informed decisions with regards to weight saving options.
So far, I can share the following data.

Preamble: the unsprung mass of the 4 stock 19 inch wheels plus brakes EXCLUDING suspension parts is:
Tires: 120 lbs
Wheels : 116 lbs
Brake rotors: 98 lbs
Brake calipers and pads approx. 85 lbs
Total 420 lbs or 192 Kg
Make this a nice round 500 lbs with suspension parts for the sake of simplicity.

Now let us look at how we can reduce weight by upgrading the brakes:

1) Keeping factory 19 inch wheels and only replacing all 4 factory rotors with same size two piece steel rotors from one of the well known aftermarket suppliers will save 22 lbs / 10 Kg of unsprung mass.
2) The Tesla Track Pack brake rotors shave another 11 lbs / 5 Kg for a total of 33 lbs or 15 Kg. I could not find enough data to determine if the Track Pack calipers are lighter or heavier than stock. I guess same weight at best.
When looking at potential weight savings with Track Pack, we must consider that it is not possible to keep the 19 inch factory wheels and so we must account for the weight difference between these and the 20 or 21 inch wheels and tires, which are - well larger!
Track Pack wheels are marginally heavier (10 lbs total).
Only a handful of forged ultra light wheels will provide a meaningful weight saving on the wheel/tyre set versus the stock 19 inch.
Furthermore, any 21 inch wheel, regardless of its manufacturing process will have a lot of mass located in the (larger) barrel which, resulting in a larger polar moment. So some of the weight savings (if any) will be lost in terms of rotational inertia due to this.
3) As an alternative to solution 1, one could install same size Carbon Ceramic brake rotors from RacingBrakes.
The unsprung weight savings are a whopping 50.2 lbs or 22.6 Kg but there is a catch: the cost. Parts alone are above 10 K USD.

So long story short: if you want to keep the 19 inch wheels, it is possible to save 50 lbs / 22 Kg on the brakes for 12 K USD installed and half of that for 4 K USD installed. This is roughly 10% or 5% of the unsprung mass.

I hope this was useful. Let me know if you'd like more comparisons and please provide data if you have any that would be relevant (for example caliper weights). Thanks

FYI I think you pretty much always need to upsize rotors when going CCB as they have a lower coefficient of friction than steel

 

[Sam1]

Hello everyone, I am new here and it will be my first Tesla.
I did a test drive with a 2023 Model S and found many things I loved and enough I hated that I am now sitting on the side line waiting for the fix to Tesla Vision.
If and when I buy, it will be an S Plaid (for the engineering prowess although the S Long Range was plenty fast enough).
One thing I like about the new S generation is the weight reduction. Wow!
I did not do an A/B comparison but it seems logical that the lighter cars should handle better. I am surprised this is not debated so much here?
And so, while waiting, I wondering about how to further reduce weight. I don't do track driving but I like a nimble car and we have lots of curvy roads where I live.
So far I have found the following possibilities:
- brakes
- wheels
Can anyone here with real world before/after experience give feedback on these mods? Does this make a significant/perceptible difference?
Vendors talk about unsuspended mass and rotational inertia. I get it but wonder whether such nuances will be perceptible given the car's weight?
And if you have other weight saving ideas...
Thanks

You will see almost absolutely no performance benefit from weight reduction on wheels and brakes.

You will see an increase in handling performance and/or braking performance.

With the 21" OEM setup that weighs roughly 30 pounds more than the 19" OEM setup, you get roughly two tenths variation at the drag strip between the two...however, I personally believe most of that variation is related to the additional resistance at the top end of the track and worse launch from the profile of the 21" tire itself.

It's not necessarily the car's weight that makes the difference here, the car has so much excess power at lower speeds that the limitation is traction, and not momentum.

 

[SilverGS]

You will see almost absolutely no performance benefit from weight reduction on wheels and brakes.

You will see an increase in handling performance and/or braking performance.

With the 21" OEM setup that weighs roughly 30 pounds more than the 19" OEM setup, you get roughly two tenths variation at the drag strip between the two...however, I personally believe most of that variation is related to the additional resistance at the top end of the track and worse launch from the profile of the 21" tire itself.

It's not necessarily the car's weight that makes the difference here, the car has so much excess power at lower speeds that the limitation is traction, and not momentum.

Exactly!

It's no different than splitting hairs lol

 

[flyingfish28]

You will see almost absolutely no performance benefit from weight reduction on wheels and brakes.

You will see an increase in handling performance and/or braking performance.

I like this discussion, but before saying another word I must state again that I am new to Tesla with all of 12 hours of demo time on a Model S 23.
So take all I say as just chit chat with an interested guy - I am not pretending that I know anything.

Earlier in the thread I estimated unsuspended mass to be around 500 lbs or roughly 10% of the vehicle's weight. This puts many things in perspective and supports your statement that we would not see significant performance changes form reducing this.

Actually, my post was meant to inform other newbies like me about the numbers that took hours to dig out.
Many parts sellers here are touting the advantages of lightweight stuff. I was curious to know how much weight can be saved at what cost.

I have never driven such a heavy car hard, and I am glad that you suggest less unsuspended mass could lead to better handling and braking.
Now this appeals to me because high speed is simply not feasible where I live (100 mph = jail) but we do have mountains and good curvy roads.

So i'll be good on the highway and then *may* go to track mode for that 20 minute drive up to the chalet, conditions allowing...
That's where better handling may become rewarding...

 

[Sam1]

I like this discussion, but before saying another word I must state again that I am new to Tesla with all of 12 hours of demo time on a Model S 23.
So take all I say as just chit chat with an interested guy - I am not pretending that I know anything.

Earlier in the thread I estimated unsuspended mass to be around 500 lbs or roughly 10% of the vehicle's weight. This puts many things in perspective and supports your statement that we would not see significant performance changes form reducing this.

Actually, my post was meant to inform other newbies like me about the numbers that took hours to dig out.
Many parts sellers here are touting the advantages of lightweight stuff. I was curious to know how much weight can be saved at what cost.

I have never driven such a heavy car hard, and I am glad that you suggest less unsuspended mass could lead to better handling and braking.
Now this appeals to me because high speed is simply not feasible where I live (100 mph = jail) but we do have mountains and good curvy roads.

So i'll be good on the highway and then *may* go to track mode for that 20 minute drive up to the chalet, conditions allowing...
That's where better handling may become rewarding...

You'll see the handling benefits at slow speeds just as you would higher speeds. With less weight (of any sort), the suspension can react quicker to changes. Lighter wheels and brakes aren't just for acceleration, even on ICE cars it's more for handling for the reason above.

 

[Unclepaul]

Forever, people have lightened cars to improve performance.
Problem is that when you gain performance by lightness, you spend $, comprimise safety and need to adjust the suspension to realize the better handling.

Tesla offers a ceramic brake package that will reduce weight and improve issues with brake fade.

Changing out to lighter wheels will comprimise the crashibility of your structure. Often times heavier wheels are requried to pass crash absorbent tests.

On the other hand, Model S Plaid is an amazing well rounded performance offering. Fast enough for most, but of course not fast enough for everyone.

 

[flyingfish28]

Forever, people have lightened cars to improve performance.
Problem is that when you gain performance by lightness, you spend $, comprimise safety and need to adjust the suspension to realize the better handling.

Tesla offers a ceramic brake package that will reduce weight and improve issues with brake fade.

Changing out to lighter wheels will comprimise the crashibility of your structure. Often times heavier wheels are requried to pass crash absorbent tests.

On the other hand, Model S Plaid is an amazing well rounded performance offering. Fast enough for most, but of course not fast enough for everyone.

I think this is a totally reasonable post applied to a totally unreasonable proposition.
People who buy Plaids (probably me, soon) do not think this way.
The Plaid is ridiculously excessive and there is no rational justification for it from 99% of buyers who are not drag racers.

When we buy a Plaid we are satisfying some very personal need.
In my case, I had given up on cars 10 years ago, but the engineer in me just HAS TO experience this: A computer, a rocket engine, four wheels.

It is so disruptive, it is intriguing. I just have to experience this.

Even a model S would be far too powerful for my use case.
Now add to it the desire of removing the ugly "musko-cheapo" side from it and there you have it: we want our own, kind of unique Plaid.
Look at @bkcyk's car above - it is a different totally individual piece of automotive art...

That's why. And frankly whether it will deform better in case of a frontal crash is slightly irrelevant to this equation.

 

[flyingfish28]

On the Engineering Perspective youtube channel, they found and compared the published EPA data about fuel efficiency of the various Model S wheel options. The real world difference between the 19 inch + aero cover and 21 inch Arachnid is documented!

I found this graph particularly useful. It compares total resistance to forward movement (aka "Road Load") vs speed.
On that graph the data is displayed as % improvement of the 19 inch wheel plus aero cover versus the 21 inch Arachnid baseline.

As you can see, the 19 inch are vastly better, especially at low speeds. But wait: there's a catch.

This is a PERCENTAGE difference. And the absolute value is very very small: : at 50 mph, the Road Load is about 12 HP.

What does this mean?
Well simply that the efficiency advantage will be only perceptible in range.
The slower our average speed, the bigger the benefit.
At 3 digit speed, the range benefit tapers to 5%. Still a lot if you ask me.
At speeds below 50 mph, the advantage of the 19 inch wheels is predominantly due to the lower polar moment - the wheels resistance to acceleration. This is why I believe that the 19 inches should deliver a more pleasant experience in this speed bracket.

Taking this further, it is not about the weight of the wheel, but the energy required to "spool it up".
This energy is a function of the polar moment.
Polar moment is roughly mass x radius. And we sometimes forget about the elephant in the room: the tyre!

A wider tyre (e.g. 315 vs 265) has more mass located at the largest diameter station: bad.
A wider tyre will deliver more adherence (good if we need it ) but at the cost of more friction (bad if we want efficiency)
Increasing wheel diameter (21 vs 19) implies a larger diameter "barrel" , where the bulk of the wheel's mass is located : bad
Increasing wheel diameter will also remove compliance from the tyre (good if we need it but bad for comfort)

So the short of this is:
Efficiency, range, comfort and nimble handling at non-highway, non racing speeds -> 19 inch. Aero covers double the efficiency gain at 60 mph and become dominant above this speed.
Racing and very high speed adherence: lightweight 21 inch (not Arachnids) with careful tyre choice
Sporty looks : 21 inch Arachnid.

Since I do not intend to race and 90 mph will land me in jail, my (soon to be) Plaid will have 19 inches and aero covers for starters. We'll see then...

 

[Sam1]

On the Engineering Perspective youtube channel, they found and compared the published EPA data about fuel efficiency of the various Model S wheel options. The real world difference between the 19 inch + aero cover and 21 inch Arachnid is documented!

I found this graph particularly useful. It compares total resistance to forward movement (aka "Road Load") vs speed.
On that graph the data is displayed as % improvement of the 19 inch wheel plus aero cover versus the 21 inch Arachnid baseline.
View attachment 993668

As you can see, the 19 inch are vastly better, especially at low speeds. But wait: there's a catch.

This is a PERCENTAGE difference. And the absolute value is very very small: : at 50 mph, the Road Load is about 12 HP.

What does this mean?
Well simply that the efficiency advantage will be only perceptible in range.
The slower our average speed, the bigger the benefit.
At 3 digit speed, the range benefit tapers to 5%. Still a lot if you ask me.
At speeds below 50 mph, the advantage of the 19 inch wheels is predominantly due to the lower polar moment - the wheels resistance to acceleration. This is why I believe that the 19 inches should deliver a more pleasant experience in this speed bracket.

Taking this further, it is not about the weight of the wheel, but the energy required to "spool it up".
This energy is a function of the polar moment.
Polar moment is roughly mass x radius. And we sometimes forget about the elephant in the room: the tyre!

A wider tyre (e.g. 315 vs 265) has more mass located at the largest diameter station: bad.
A wider tyre will deliver more adherence (good if we need it ) but at the cost of more friction (bad if we want efficiency)
Increasing wheel diameter (21 vs 19) implies a larger diameter "barrel" , where the bulk of the wheel's mass is located : bad
Increasing wheel diameter will also remove compliance from the tyre (good if we need it but bad for comfort)

So the short of this is:
Efficiency, range, comfort and nimble handling at non-highway, non racing speeds -> 19 inch. Aero covers double the efficiency gain at 60 mph and become dominant above this speed.
Racing and very high speed adherence: lightweight 21 inch (not Arachnids) with careful tyre choice
Sporty looks : 21 inch Arachnid.

Since I do not intend to race and 90 mph will land me in jail, my (soon to be) Plaid will have 19 inches and aero covers for starters. We'll see then...

Kind of curious if the 21 is just a genius design, or if it has more to do with the car directing air differently at higher speeds.