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Shocked by the new Roadster rolling out of the Tesla Semi!

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I'm questioning whether the 200kWh is in there NOW. And whether it's using cell tech used today, or something still under development. For S&X Elon couldn't see the needd for more than 100kWh even when whole countries with huge markets really, really wanted it, and to pay for it. Roadster, just do nearly triple the Model 3? Makes no sense unless there has been a breakthrough. Same breakthrough may be instrumental to squeeze 500 miles of range into a sleek semi tractor, also for 2020.
My guess is that there is some of breakthrough with the cooling breakthrough documented in the P100d, but for 2170 cells, and I'm super curious about the fuses and the gearing of the 3rd motor.... my other guess is that everything in the car is extremely light.... even the wheels look to be carbon fiber
 
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My guess is that there is some of breakthrough with the cooling breakthrough documented in the P100d, but for 2170 cells, and I'm super curious about the fuses and the gearing of the 3rd motor.... my other guess is that everything in the car is extremely light.... even the wheels look to be carbon fiber
Carbon wheels tend to need bigger spokes. And the cost is immense. Not something for a $200K car.
Even if the cooling were to weigh nothing, 200kWh in 2170 cells such as used in Model 3, will be a hefty business. The way the Roadster is built doesn't seem like a featherweight to end up at or under 2000kg with a doubled pack (and inverters). Too mainstream a design for that.
Let's not forget that there are 3 (likely big) motors. The Model 3's standard motor will not do.
 
Could be. The seat bottom is well below the door opening though, which in turn is not hugely high.
Are we looking at the same pictures? To me all the evidence, from first hand accounts to pictures and video, points to a double layer pack. The most simple explanation is they put in 2 of the Model 3 80kWh packs for a total of 160kWh and they expect to be able to push that to at least 200kWh by 2020.
 
I can't imagine a double layered pack after, then the world begged for a 100kWh Model 3, they could only fit 75kWh.
The world has been begging for affordable cars with reasonable range. The Model 3 80kWh pack is plenty large enough for that segment.

In road cars, a higher floor is a trend, not a problem, right?
Big problem because up right seating is also a trend, meaning your feet need to be below you, not stretched way out in front the way the Roadster is. A higher floor means an even higher roofline, and the Model 3 roof line is already rather high.
 
The world has been begging for affordable cars with reasonable range. The Model 3 80kWh pack is plenty large enough for that segment.


Big problem because up right seating is also a trend, meaning your feet need to be below you, not stretched way out in front the way the Roadster is. A higher floor means an even higher roofline, and the Model 3 roof line is already rather high.
Audi showed drawings where the middle row foot bed was single layer, under the seats double layer. If not so much range is needed, foot bed could be lowered some 10cm. Imagine how comfy Model S would be. I'd rather have that space than the rear trunk well.
 
Carbon wheels tend to need bigger spokes. And the cost is immense. Not something for a $200K car.
Even if the cooling were to weigh nothing, 200kWh in 2170 cells such as used in Model 3, will be a hefty business. The way the Roadster is built doesn't seem like a featherweight to end up at or under 2000kg with a doubled pack (and inverters). Too mainstream a design for that.
Let's not forget that there are 3 (likely big) motors. The Model 3's standard motor will not do.
Up close, everything to me looked to be in carbon fiber.... especially some really tiny details in the rear diffuser.... I don't think the weight savings can be underestimated. I don't think the car will be light compared to a mcclaren, but I do think it will be very light for a tesla.
IMG_4688.JPG
 
Are we looking at the same pictures? To me all the evidence, from first hand accounts to pictures and video, points to a double layer pack. The most simple explanation is they put in 2 of the Model 3 80kWh packs for a total of 160kWh and they expect to be able to push that to at least 200kWh by 2020.
I think you're right and it's also possible that they have a recess in the top layer under the seats where they could have removed or relocated one sheet on each side to allow the lowest part of the seat to be a couple inches lower.
 
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Why are people questioning teslas ability to fit 200 kWh worth of battery in the roadster?
They have always come through on their advertised battery capacities.


Having said that, one of the main reasons I’ll be buying this car is for the range. So they better deliver.

Have you not read Calculate usable battery capacity based on rated miles values or any subsequent threads?



  • [*]Model S 60 (s/w limited 75): 210 rated miles * 295 Wh/mi = ~62 kWh usable
    [*]Model S 75: 249 rated miles * 295 Wh/mi = ~73.5 kWh usable
    [*]Model S 60D (s/w limited 75): 218 rated miles * 285 Wh/mi = ~62.1 kWh usable
    [*]Model S 75D: 259 rated miles * 285 Wh/mi = ~73.8 kWh usable
    [*]Model S 90D: 294 rates miles * 285 Wh/mi = ~83.8 kWh usable
    [*]Model S P100D: 315 rated miles * 314 Wh/mi = ~98.9 kWh usable (* Estimated Wh/mi)
    [*]Model X 75D: 237 rated miles * 320 Wh/mi = ~75.8 kWh usable
    [*]Model X 90D: 257 rated miles * 320 Wh/mi = ~82.2 kWh usable
    [*]Model X P100D: 289 rated miles * 342 Wh/mi = ~98.8 kWh usable
Now that said I totally believe that the 200 kWh pack is doable and they'll get it within 10 kWh of advertised. I sure won't be complaining if it is 190 kWh usable with a 200 kWh nameplate as I won't be buying such an expensive car.

I just thought it odd to see someone say no one has reason to question the relative accuracy of kWh nomenclature on Tesla cars.
 
May I also just add a WTF on this photo? I mean, they have a 200 kWh battery and for god's sake look how high off the ground the diffuser is between the rear wheels!

The battery doesn't go behind the rear axle so they can put the rear most part of diffuser as high as they want, it only affects cargo space in the trunk not battery space. I'd say it drops down to meet the bottom of the battery pack right at the axle.
 
The battery doesn't go behind the rear axle so they can put the rear most part of diffuser as high as they want, it only affects cargo space in the trunk not battery space. I'd say it drops down to meet the bottom of the battery pack right at the axle.

Yes I think you are right. The thing I wonder about is how much of this has to do with high speed stabilization versus cutting weight? To go a full 100 mph faster than what the S currently does is whole different engineering task.
 
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Have you not read Calculate usable battery capacity based on rated miles values or any subsequent threads?


Now that said I totally believe that the 200 kWh pack is doable and they'll get it within 10 kWh of advertised. I sure won't be complaining if it is 190 kWh usable with a 200 kWh nameplate as I won't be buying such an expensive car.

I just thought it odd to see someone say no one has reason to question the relative accuracy of kWh nomenclature on Tesla cars.
Usable and actual capacity are obviously going to be different
You actually proved my point, so thanks
 
Okay, I played around a bit with a spreadsheet to figure out a bit about how close I am to workable assumptions.

Assumptions about the Roadster are like this:

- 1900 kg including driver
- 600 kW output max
- 156+ kWh battery
- 1.9 square meter front area
- Cd of 0.25
- Max force 27460N
- Crr of 0.008
- Gear ratio of 5.5
- Similar motor characteristics as Model S

And I arrived at these graphs:

View attachment 261318

View attachment 261319
- 0-100 km/h without rollout would be 2.02 seconds.
- 0-160 km/h without rollout would be 4.08 seconds.
- 0-200 km/h without rollout would be 6.04 seconds.
- 0-300 km/h without rollout would be 15.13 seconds.
- 0-400 km/h without rollout would be 88.84 seconds.

- 0-100 km/h with 1 ft rollout would be 1.82 seconds.
- 0-160 km/h with 1 ft rollout would be 3.88 seconds.
- 0-200 km/h with 1 ft rollout would be 5.84 seconds.
- 0-300 km/h with 1 ft rollout would be 14.93 seconds.
- 0-400 km/h with 1 ft rollout would be 88.64 seconds.

Quarter mile (1 ft rollout, 402m) would be ~9.0 seconds at 245 km/h (152 mph)
I'll just post this here as well. It goes well beyond calculating the required battery size. ;)
 
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High diffusers on street cars are just for show. The floor profile and height above the ground do not support massive divergence in the rear. The flow simply separates as opposed to speeding up.

It does look sexy.
So even with a flat bottom and a bit of suspension lowering at high speeds, the ground clearance of a street car is too great for the Bernoulli principle to produce downforce? So diffusers are as useless as the decorative rear wings a few decades ago? That's interesting.
 
If it actually specs out, it's a bargain.:D
Wifey said if she could trust Tesla Motors, we can put a down on one. The quickest either of us has gone is low 9's. IIRC, I have her beat there with a 9.34 ET.

To run 8.9 in the 1/4 with a full bodied car you need a NHRA Super Gas license, a full certified safety cage, a parachute, etc. Most cars that run at those ETs are trailer queens if plated.

You will not be able to run it at a normal dragstrip on a normal day. You would have to rent the track out if they allow it. It's an insurance thing. I doubt California Speedway (Fontana) would let you run it even if you rent the track. They were already sued because somebody lost control of their car. This was a rented track day with wavers signed absolving the track of liability. Porsche took it in the shorts too.
 
If it actually specs out, it's a bargain.:D
Wifey said if she could trust Tesla Motors, we can put a down on one. The quickest either of us has gone is low 9's. IIRC, I have her beat there with a 9.34 ET.

To run 8.9 in the 1/4 with a full bodied car you need a NHRA Super Gas license, a full certified safety cage, a parachute, etc. Most cars that run at those ETs are trailer queens if plated.

You will not be able to run it at a normal dragstrip on a normal day. You would have to rent the track out if they allow it. It's an insurance thing. I doubt California Speedway (Fontana) would let you run it even if you rent the track. They were already sued because somebody lost control of their car. This was a rented track day with wavers signed absolving the track of liability. Porsche took it in the shorts too.
I agree this is a problem. People will end up doing these runs on public roads, which is far less safe than a proper drag strip.
 
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If it actually specs out, it's a bargain.:D
Wifey said if she could trust Tesla Motors, we can put a down on one. The quickest either of us has gone is low 9's. IIRC, I have her beat there with a 9.34 ET.

To run 8.9 in the 1/4 with a full bodied car you need a NHRA Super Gas license, a full certified safety cage, a parachute, etc. Most cars that run at those ETs are trailer queens if plated.

You will not be able to run it at a normal dragstrip on a normal day. You would have to rent the track out if they allow it. It's an insurance thing. I doubt California Speedway (Fontana) would let you run it even if you rent the track. They were already sued because somebody lost control of their car. This was a rented track day with wavers signed absolving the track of liability. Porsche took it in the shorts too.
I knew I knew you from somewhere!