MyTeslaWeekend Rumor - Dual Motor only for the first 500k units produced!

[Crissa]

Is there any reason why they couldn't use the same casting in both front and rear regardless of the drive unit? That is, could they design the front and rear to accommodate both a single or dual motor setup? They certainly have had the time, and it would be easier for them in the long run. I am thinking that they are putting the same suspension and 4WS in all of the CTs and those would have a major impact on the casting design, maybe more so that the drivetrain arrangement.

Yeah. That is something I hinted strongly at, pointing out they ise the same motor cover chassis design across the Model 3/Y range and possibly into the Model S. Fewer parts is better.

Sure you could save some weight for each motor, but the gigacastings are much, much cheaper than custom units for each configuration.

I was wondering if it might even be possible to design the motor/steering combined unit to use nearly the same in the front and the back, saving them even more in build complexity.

-Crissa

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[Throwcomputer]

BEV adoption is still in it's infancy. For the sake of argument lets call 2010 year zero with the introduction of the Roadster. We are still less than 5% cumulative saturation. On most of these curves true mass production for the masses doesn't take off until 10% saturation.

Most of us are still considered early adopters and we will probably pay a premium in the next couple years. Cost will start to drop in 2024 or so when supply chain catches up to demand and more options are available.

I guess my point is that Tesla doesn't need to force too many options. They can't change the curve by themselves. They will be a leader and push boundaries, but won't sacrifice overall profit. That is why they are not concentrating on the model 2 and may not make the CT3 or it's equivalent in the next couple years.

Rumors are rumors until published on the Tesla site. This is just speculation but there is some support.

2021-2022 is really year 1 of wider ev adoption. It's finally started to go from a rare novelty to something that will become very common as Tesla's output increased enough where you see them often on the road. But more importantly, the number of ev models released and being released in the next year or two is crazy! There are so many options for new buyers now, so even if you hate Tesla, you can go get one from legacy manufacturers.

If I were getting a sedan, I would be seriously looking at Kia and Hyundai options as those are the most exciting of the non Tesla options. Out of all the legacy manufacturers, I have a feeling both of them will start to rise in prominence, to the point of being high end and quality brands with ev adoption, while the current well respected legacy brands that are much higher on the list of respected brands will start to fall off the top of that list sharply.

 

[Tinker71]

Why would they limit dual motor to rear wheel drive only? Merely to differentiate trim levels?

To limit the number of sub assemblies. I think the CT2 (middle) might actually have 3 motors. Just a WAG.

 

[Bill906]

Is there any reason why they couldn't use the same casting in both front and rear regardless of the drive unit?

I'm sure it's "possible" to use the same casting front and back. The question is, do the advantages of that outweigh the disadvantages. That may require significantly more weight on one end that isn't needed but is needed on the other end. I suspect the amount a rear wheel can turn (steering angle) is significantly less than the front wheels. It might be dangerous to have the rear wheels physically be able to turn (steering) more than a specific amount. Just throwing out some example reasons I can think of, there are many reasons we don't have the information needed to even consider.

Now if your question is can you have the same casting have only one motor, or two motors, I would say not likely. If you only have one motor, you'll need a differential to connect that one motor's torque to both wheels. Two motors does not require the differential. I'm not saying it's impossible, but I would say it's highly unlikely.

 

[Crissa]

I'm sure it's "possible" to use the same casting front and back.

They may use the same motors, but not the same casting: The loads for the bed vs the front firewall (which the gigacasting replaces) are vastly different.

It would be a very different vehicle for it to be symmetrical from the wheel arches.

-Crissa

 

[Jhodgesatmb]

I'm sure it's "possible" to use the same casting front and back. The question is, do the advantages of that outweigh the disadvantages. That may require significantly more weight on one end that isn't needed but is needed on the other end. I suspect the amount a rear wheel can turn (steering angle) is significantly less than the front wheels. It might be dangerous to have the rear wheels physically be able to turn (steering) more than a specific amount. Just throwing out some example reasons I can think of, there are many reasons we don't have the information needed to even consider.

Now if your question is can you have the same casting have only one motor, or two motors, I would say not likely. If you only have one motor, you'll need a differential to connect that one motor's torque to both wheels. Two motors does not require the differential. I'm not saying it's impossible, but I would say it's highly unlikely.

I am not convinced that having one or two gearboxes and drive shafts needs two different castings. Tesla is already using parts across multiple vehicles in different ways. The argument of extra weight I do buy into. The question is: how many unique castings are needed for the CT fleet. Could we do it with 2? It seems like @Crissa thinks 4 is the minimum but [much] earlier suggested using the same casting front and rear (which I thought was an intriguing idea).
I do not see the casting as impacting turn angles. If they are going to have 4WS then they need room for the wheel to turn and of course they need the room and support for steering hardware. The amount of steering is probably software controlled.

 

[Crissa]

I am not convinced that having one or two gearboxes and drive shafts needs two different castings.

It's not the motors, I think that need different castings: It's merely front vs back. The front casting includes the firewall.

-Crissa

 

[TyPope]

Is there any reason why they couldn't use the same casting in both front and rear regardless of the drive unit? That is, could they design the front and rear to accommodate both a single or dual motor setup? They certainly have had the time, and it would be easier for them in the long run. I am thinking that they are putting the same suspension and 4WS in all of the CTs and those would have a major impact on the casting design, maybe more so that the drivetrain arrangement.

They may put the same components in ALL CTs but they may skip out on the actuators for 4WS on the cheaper models and just blank them in place. That'd let them save money on the components while simplifying the number of parts needed to make two versions.

 

[TyPope]

Yeah. That is something I hinted strongly at, pointing out they ise the same motor cover chassis design across the Model 3/Y range and possibly into the Model S. Fewer parts is better.

Sure you could save some weight for each motor, but the gigacastings are much, much cheaper than custom units for each configuration.

I was wondering if it might even be possible to design the motor/steering combined unit to use nearly the same in the front and the back, saving them even more in build complexity.

-Crissa

I'll bet you are right that they use the same front and rear components save the motors in all configurations and just block off or use blanks to lock the rear steering in place... sort of like they made the Model S center display NOT be able to rotate by taking the motor out.

 

[Crissa]

They may put the same components in ALL CTs but they may skip out on the actuators for 4WS on the cheaper models and just blank them in place. That'd let them save money on the components while simplifying the number of parts needed to make two versions.

I hope they don't blank out four wheel steering, as it is a safety product.

-Crissa

 

[Jhodgesatmb]

It's not the motors, I think that need different castings: It's merely front vs back. The front casting includes the firewall.

-Crissa

I saw the Munro Live segment where they showed the Modrl Y front casting and it looks like there is no firewall and I seem to recall their saying that the front casting is replacing the functionality of the firewall, not being a firewall. Did you hear it differently?

 

[TyPope]

I hope they don't blank out four wheel steering, as it is a safety product.

-Crissa

Well, really, it's a convenience feature more that safety. They can use force vectoring through braking for stability control. The 4WS just lets us park easier and change lanes while maintaining heading. For safety, I can't see what it does that would help... or else more vehicles would be doing it despite cost.

 

[Crissa]

I saw the Munro Live segment where they showed the Modrl Y front casting and it looks like there is no firewall and I seem to recall their saying that the front casting is replacing the functionality of the firewall, not being a firewall. Did you hear it differently?

I'm in the camp that if it does the function, it's that part. If it does the function of a firewall, replaces the firewall; how is the firewall not a part of it?

Well, really, it's a convenience feature more that safety. They can use force vectoring through braking for stability control. The 4WS just...

It provides much higher stability at highway speeds and the moose test. Not to mention with a trailer. Torque vectoring doesn't match.

-Crissa

 

[Jhodgesatmb]

I'm in the camp that if it does the function, it's that part. If it does the function of a firewall, replaces the firewall; how is the firewall not a part of it?


It provides much higher stability at highway speeds and the moose test. Not to mention with a trailer. Torque vectoring doesn't match.

-Crissa

A firewall is a wall to prevent fire from getting to the cabin. 2:45 - 3:20.

 

[Ogre]

I'm in the camp that if it does the function, it's that part. If it does the function of a firewall, replaces the firewall; how is the firewall not a part of it?

Well… it’s in the name isn’t it? If there is a firewall in a Tesla, it would be the floorpan.

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