Model 3 AWD / Performance - lower UDDS Range!

[privater]

Looks like Model S/X are designed with AWD in mind and Model 3 are mean to be RWD for a reason.

Another cue is Tesla dropped RWD on all Model S last year. There is no draw back to use AWD on every single Model S.
However, Model 3 is another story, AWD become a dilemma between best range and maneuverability/speed.

 

[TEG]

They ought to build a front motor using the new motor tech like they have in the rear...

 

[mblakele]

Wait for the EPA numbers. We don’t have the whole picture yet.

 

[apacheguy]

I doubt it's using the front motor at all in this test. Why would you use the front motor when the rear is more efficient? The difference is probably mostly the friction from the axles (CV joints), gearbox, and front motor. The weight is probably a much smaller contributor since you get most of that energy back with regen. The highway efficiency should be much closer since the most of the loss at high speed is from wind resistance and weight hardly matters at all.

Hmm. If that's true then the dual motor Model S should score lower than the RWD in this test for the same reason, frictional losses of drivetrain components.

Also, the frequent acceleration indicates to me that the AC induction motor is used and it does not enter torque sleep.

 

[apacheguy]

They ought to build a front motor using the new motor tech like they have in the rear...

Agree. The reason they went with AC induction is because the performance is greater. So for the P it makes sense. But for the non-P AWD it makes more sense to have a smaller version of the rear motor up front.

 

[EV-lutioin]

California ARB just posted their certification for the Model 3 AWD and Performance Models. The listed UDDS is 455.32 miles versus 495.1 miles for the RWD.

https://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2018/tesla_pc_a3740023_0_z_e.pdf

https://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2018/tesla_pc_a3740022_0_z_e.pdf

Wouldn't we expect the larger wheels on the performance model to lower the range by ~10% in their dyno test?

 

[MP3Mike]

Wouldn't we expect the larger wheels on the performance model to lower the range by ~10% in their dyno test?

But the P comes standard with 18"...

 

[Daniel in SD]

Looks like Model S/X are designed with AWD in mind and Model 3 are mean to be RWD for a reason.

Another cue is Tesla dropped RWD on all Model S last year. There is no draw back to use AWD on every single Model S.
However, Model 3 is another story, AWD become a dilemma between best range and maneuverability/speed.

There is no drawback to using AWD on the Model S because the motors are inefficient so with two motors they can gear them differently so that they reach peak efficiency at different speeds. The Model 3 motor is a much more efficient design. At some point they will probably update the Model S to use a switched reluctance motor.

 

[MP3Mike]

They ought to build a front motor using the new motor tech like they have in the rear...

I think the issue is that out is easier to sleep an induction motor. I don't think you can just freewheel a PM motor.

 

[Daniel in SD]

Hmm. If that's true then the dual motor Model S should score lower than the RWD in this test for the same reason, frictional losses of drivetrain components.

Also, the frequent acceleration indicates to me that the AC induction motor is used and it does not enter torque sleep.

I doubt they're accelerating 0-60 in 5 seconds in this test which you can do with just the rear motor.

 

[EV-lutioin]

But the P comes standard with 18"...

Do we know if the dyno test was done with 18" wheels?

 

[Daniel in SD]

Agree. The reason they went with AC induction is because the performance is greater. So for the P it makes sense. But for the non-P AWD it makes more sense to have a smaller version of the rear motor up front.

I believe that induction motors are cheaper and if you only use it for fast acceleration and in low traction conditions it will hardly impact efficiency. It would make sense to make a smaller version of the rear motor for the AWD. That might gain some efficiency and reduce costs. Of course maybe they'll let you unlock the full power of the rear motor for a price later

 

[Daniel in SD]

Do we know if the dyno test was done with 18" wheels?

The 18" aero wheels only help highway range right? The average speed of this test is 19.59mph.

 

[MP3Mike]

Do we know if the dyno test was done with 18" wheels?

No.

 

[apacheguy]

I doubt they're accelerating 0-60 in 5 seconds in this test which you can do with just the rear motor.

Ok, so are you saying the AC induction motor is *only* used under very heavy acceleration? The rest of the time it is dead-weight?

 

[Daniel in SD]

Ok, so are you saying the AC induction motor is *only* used under very heavy acceleration? The rest of the time it is dead-weight?

Yes. Unless there are some conditions where it is more efficient than the switched reluctance motor. Maybe they could use the front motor to reduce tire wear under moderately heavy acceleration too. All just speculation on my part. The point is that most of the time that you're driving the car and in these efficiency tests you're using very little power. The Model 3 motor is 192kW (probably much more), the battery is only ~70kWh and lasts 4+ hours.

 

[Garlan Garner]

Older Model S UDDS tests are hard to find, but here are some :

So Model S:

100D = 449.7
P100D = 414.4
75D = 345.6
75 = 333.4

What does UDDS AER mean?

 

[Garlan Garner]

I doubt they're accelerating 0-60 in 5 seconds in this test which you can do with just the rear motor.

vBox clocked 0-60 in the Model 3 at 4.4

fast forward to 12.37

 

[Knightshade]

vBox clocked 0-60 in the Model 3 at 4.4

fast forward to 12.37

That 4.4 was conducted on what appeared to be a downhill slope.

Same car tested on a flat road by the other guy did 4.6 (which is still 2/10ths better than any professional car mag review got- and bear in mind all those guys are using rollout... the official 5.1 number from Tesla isn't)

 

[jsmay311]

Tesla treats Model 3 reservations holders like mushrooms.

These tests should've been done and publicized before opening the floodgates of order invitations so that buyers could make informed decisions. And Tesla should be honest about efficiency/range differences between models instead of (apparently(?)) concealing advantages of the cheaper version by fudging the EPA numbers to make the more expensive version look better in comparison.