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cvalue13

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I don't think the physics is with you on this one

first, not to quip, but a "200% increase" of 340mi is 1,020 miles

but in any event, literally doubling the pack size does not double the range.

the truck becomes ~1,000lbs heavier just from the pack. Then the structural elements of the vehicle have to be made more robust, which increases weight. Then the steering, breaking, and other operational componentry has to become more robust, further increasing the weight, etc. So you do not get double the range by adding double the pack, even before accounting to a change in frontal plain.

But, moving just one click past talking in crayolas here, to a sharpie:

Current frontal plain height of production CT:
  • Height at medium is 70", with 9" of ground clearance, meaning the height of the frontal plane is 61"
Current frontal plain width of production CT:
  • we'll even assume that Tesla can increase the height without increasing the width, to avoid making the design look aesthetically like a stretched version of the truck
  • current width is 80"
Current frontal plain area of CT:
  • 61" x 80" = 4880 square inches
New frontal plain area of CT after becoming 6" taller"
  • 67" x 80" = 5,280 square inches
  • a 7.5% increase to frontal plain f(and so drag force) from current production frontal plain/drag force (assuming variables stay constant)
Drag Coefficient:
  • we'll even assume that Tesla can change the height of the CT's frontal plain without changing the Cd of the vehicle
  • Cd of current production CT is 0.345 (so we've seen/been told)

I have to run to appointments - who wants to complete the maths here?
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HaulingAss

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Setting expectations is a strategy. Elon needed to hit it out of the park back in 2019 to keep people from jumping to the faster competition (reverse Osborne Effect) the intervening years, helped by inflation, allowed Tesla to temper expectations, and demand.
I don't believe that's a valid analysis of actual events because Elon knew even better than you or I knew that legacy EV's wouldn't be made in high enough volumes to matter. Elon had zero fear that others would jump to Ford and Rivian, he actually knew they would, just not in large enough numbers to even matter. The N. American truck market is absolutely huge relative to any possible production of trucks by Ford, GM, Sellantis or Rivian.

Elon was simply over-optimistic about how quickly they would hit their 4680 power density, volume and cost targets, and he under-estimated inflation and materials costs, development time and production issues that would crop up. He was also riding high because he saw how quickly costs were dropping on the Model 3 and he already knew how well Model Y was coming together and how popular it would be. Then COVID hit and the world has not been the same since.

It was a confluence of factors that caused Elon to forecast too low of a price, and too soon of production, and none of those included trying to prevent people from purchasing competitors trucks. This who endeavor would have been far more successful if he had added $10K onto each trim, even though he still wouldn't have hit that pricing upon the initial release.
 

CybertruckRN1127

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I like to add that one of the spec or feature I am disappointed with is the lack of a folding mid-gate, but after a few days now, I think I am okay with it. I would rather have a vault to store my gear when I'm in San Francisco where people can't break my windows (I'm sure with enough force you can break the CT window) and fold down the seats to access my gear. Although, Tesla could just make a lockable folding seat, but I think this way the vault is more secure. Without actually touching or pushing the tonneau cover yet, I am confident to store $1,000+ gear inside and park it overnight. Maybe it may not be as safe, but Elon did say "bank vault" which is the same as saying coast-to-coast on AP in 2016. Hopefully he come close with this one. if it's secure, this is a win even without folding mid-gate.
 


Tinker71

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I don't believe that's a valid analysis of actual events because Elon knew even better than you or I knew that legacy EV's wouldn't be made in high enough volumes to matter. Elon had zero fear that others would jump to Ford and Rivian, he actually knew they would, just not in large enough numbers to even matter. The N. American truck market is absolutely huge relative to any possible production of trucks by Ford, GM, Sellantis or Rivian.

Elon was simply over-optimistic about how quickly they would hit their 4680 power density, volume and cost targets, and he under-estimated inflation and materials costs, development time and production issues that would crop up. He was also riding high because he saw how quickly costs were dropping on the Model 3 and he already knew how well Model Y was coming together and how popular it would be. Then COVID hit and the world has not been the same since.

It was a confluence of factors that caused Elon to forecast too low of a price, and too soon of production, and none of those included trying to prevent people from purchasing competitors trucks. This who endeavor would have been far more successful if he had added $10K onto each trim, even though he still wouldn't have hit that pricing upon the initial release.
The low prices lit a fire under everyone. It worked.
 

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Oh I absolutely don’t think I am smarter. In fact, I believe they have the pack size what it is because they are much smarter than I.. you are the one saying they should double stack. Implying you know better.
 

cvalue13

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Current frontal plain height of production CT:
  • Height at medium is 70", with 9" of ground clearance, meaning the height of the frontal plane is 61"
Current frontal plain width of production CT:
  • we'll even assume that Tesla can increase the height without increasing the width, to avoid making the design look aesthetically like a stretched version of the truck
  • current width is 80"
Current frontal plain area of CT:
  • 61" x 80" = 4880 square inches
New frontal plain area of CT after becoming 6" taller"
  • 67" x 80" = 5,280 square inches
  • a 7.5% increase to frontal plain f(and so drag force) from current production frontal plain/drag force (assuming variables stay constant)
Drag Coefficient:
  • we'll even assume that Tesla can change the height of the CT's frontal plain without changing the Cd of the vehicle
  • Cd of current production CT is 0.345 (so we've seen/been told)

I have to run to appointments - who wants to complete the maths here?

I see the confusion.

of course I wasn’t intending to say a car with twice the pack would result in a net range reduction of 30-40%

I was intending to say it may be 30-40% less efficient in mi/kWh at highway speeds

Normal CT Drag area = CdA = 0.345 * 3.1483 m2 = 1.083 m2

Mutant CT Drag area = CdA = 0.345 * 3.4064m2 = 1.1752 m2

Fd=1/2×ρ×CdA×v2 where ρ(air density) = 1.225 kg/m³ (at ~sea level/normal temp), CdA(drag area) = 1.083 m², and v(velocity) = 75mph×0.44704 = 35.78 m/s

comes to, @75mph, an Fd ≈ 0.8407 kilowatts for the normal CT, and Fd ≈ 1.02907 kW for the mutant CT

So approximately 18.25% more energy @75mph to move the mutant CT compared to anormal CT, based only on change in CdA from increasing frontal plain for a 6” pack

In addition to that, add the increased rolling resistance from all the added weight (pack, structure, components). and higher still from add of further any degradation of Cd (from pot belly pack hanging below), and higher still.

let’s call it a combined 25% greater energy requirement to move the mutant CT the same distance at 75mph, which reaches ~30% around 80mph

Which is basically why the Hummer’s 200kWH+ pack only gets 380mi of range, is slower and has poorer braking, towing, payload, and handling, but costs 30% more
 


HaulingAss

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. Not many people need 17" of ride clearance.
17" of ground clearance is HUGE ground clearance! But I don't think it's the actual ground clearance (only in "extract" mode). It's possible it's not even driveable in this mode, at least not faster than perhaps 3 mph. More details from Tesla or early buyers will let us know.

This is not a downside in my mind, if it can drive at even 15 mph with 13-14 inches of ground clearance, that's pretty huge right there relative to other vehicles sold for off-road use.

I see the Cybertruck really excelling at comfortably eating up the miles on rugged trails at 15-45 mph in relatively cushy comfort.
 

HaulingAss

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I guess I am spoiled, I bought a silverado at the bottom of the recession in 2009 when no one was buying trucks for 28 K (including taxes) in Canadian dollars!
I'm guessing it wasn't new and it didn't have 4x4 (or an awesome stereo and seats, lol!).
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