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Will RWD go extinct too?

Discussion in 'Model S' started by Maximilien, Apr 23, 2017.

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Will RWD be gone in Model S in the future?

  1. Yes, very likely.

    58 vote(s)
    49.6%
  2. No, not likely.

    59 vote(s)
    50.4%
  1. AmpedRealtor

    AmpedRealtor Well-Known Member

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    LOL I wouldn't exactly call it "huge".
     
  2. DIL

    DIL Member

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    weight distribution is a factor in handling too. do the RWD cars get closer to the ideal 50/50 weight distribution?
     
  3. Skotty

    Skotty 2014 Model S P85

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    #63 Skotty, Apr 26, 2017
    Last edited: Apr 26, 2017
    We need a scientific test of the various models to see how efficient they really are. Like an indoors, climate controlled, highway speed test of the various models to see how their efficiency compares. There are just too many variables. At 70+ MPH, I can get anywhere from 290 to 450 wh/m depending on weather and road conditions in my 2014 P85 w/ 19" Michelins. I'd say typical non-winter is about 320 wh/m in the 70 - 75 MPH range. Winter typical is probably around 390 iirc. That's midwest interstate with hills, for whatever difference that makes.

    I know. Hard to find an indoor track where you can cruise at 70+ MPH. But that is what is needed for a properly controlled comparison.

    Ideally, if I could have whatever I wanted, I'd want to see the following tests:

    Cars (all Model S):
    85, P85, 60D, 85D, P85D, 90D, P100D

    Tests (focus on typical interstate speeds and typical travel temps):
    70 MPH constant speed (with and without hills, tested at 50 and 80 degrees F)
    75 MPH constant speed (with and without hills, tested at 50 and 80 degrees F)
    80 MPH constant speed (with and without hills, tested at 50 and 80 degrees F)

    All tests with 19" tires and climate control set on automatic at 70 degrees F.

    Throw in a couple of additional tests with whichever models (don't care which) with the typical 21" tires for tire spot comparison.
     
  4. jelloslug

    jelloslug Active Member

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    Over 25% difference in highway range is huge.
     
  5. WarpedOne

    WarpedOne Supreme Premier

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    The difference between S85, P85 and 85D, P85D etc is totally specific to those models and HW (and setup!) used.

    That difference is totally irrelevant for M3 or any other car.
    AWD using same level of tech is less efficient than RWD or FWD.
    Because physics.
     
    • Like x 1
  6. d.c.palmer

    d.c.palmer 8 years of EV driving

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    That's really impressive! What kinds of speeds are you travelling - and do you have climate control turned on? (The big killer is heating - which I try to avoid, using seat heating instead - but a/c will have some effect.)
     
  7. d.c.palmer

    d.c.palmer 8 years of EV driving

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    By way of comparison, our old Nissan Leaf - driven under similar conditions to our Teslas - managed about 240 Wh/mi (c.f. 315 Wh/mi for the Tesla Model S P85).

    This is, of course, an unfair comparison - the Nissan Leaf being much lighter, slower and generally less capable - but it's still interesting to compare the different vehicles. I'm sure Tesla could improve range without needing bigger battery packs, by using lighter materials and more efficient use of energy.
     
  8. jelloslug

    jelloslug Active Member

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    I run with the traffic so it's usually 70+ MPH or so. AC on, heat is a big killer though like you said. I did an experiment where I kept it below 65 on the expressway and it was down in the 220s for wh/m.
     
  9. jelloslug

    jelloslug Active Member

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    I had similar consumption in my Leaf also, the i3 was surprisingly not quite as good as the Leaf. I expected it to be better.
     
  10. Zextraterrestrial

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    I am really curious how much/if the D faster in autocross than a P85? and how is it classed? I have only driven your P85D that one time, I would love to try a D in AutoX. Maybe throw the RE71R's on it :eek:

    48 / 52
     
  11. Skotty

    Skotty 2014 Model S P85

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    So you can't turn off traction control on a D? Without traction control, I wonder if you could get a 4 tire peel out. That would be something to see.

    Come to think of it, I have no idea how power distribution between the wheels is handled on a Tesla. Anyone know how this works on a Tesla? Is it limited slip? Classic limited slip differential (even if so, probably in an unconventional packaging) or some freaky Tesla creation?
     
  12. jaguar36

    jaguar36 Active Member

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    Front rear are completely separate so they are just controlled by the motors. Left/Right is an open diff and the brakes are used to mimic a limited slip. Its a common system that works well enough on the street, not great on the track, but then Model S has no business on a track.
     
  13. brianman

    brianman Burrito Founder

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    Correct.
     
  14. Maximilien

    Maximilien Member

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    Looks like 52 people are winners here that RWD is gone to increase the gap between Model S and Model 3 ;)
     
    • Disagree x 1
  15. Stangography

    Stangography Member

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    If there is no P in front the P85 is still the faster MS... LOL... go P85... 0-60.png
     
  16. David99

    David99 Active Member

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    The confusion about dual motor cars being more efficient is the motor type. RWD cars only come with the more powerful but less efficient large motor. dual motor cars come with two smaller but more efficient motors. dual motor car with the performance option come with a small one in the front and a large one in the back.

    Now we all know about torque sleep. It's the ability of the car to turn off one motor completely and just drive on a single one. That's exactly what the dual motor cars do and that is why they are more efficient. They turn off one motor and only drive the other one. The car becomes a FWD or RWD car! Unfortunately Tesla does not make a RWD car with the small motor in the back only. That one would be the most efficient car! The small motor alone would not have enough power to make the Model S/X quick enough.

    In other words, dual motors is not what make the car more efficient. It's the fact the only dual motor cars have the small motor and with torque sleep they run on a single small motor that is more efficient.
     
  17. WarpedOne

    WarpedOne Supreme Premier

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    Same old big == inefficient that is just wrong, but nevertheless repeated ad nauseaum.
    This is true with ICE but wrong in general with electric motors.
    D is more efficient due to newer and more efficient design of the inverters.

    You don't want believe my word?
    You don't have to:
    Learn 1
    Learn 2
     
    • Informative x 1
    • Like x 1

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