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Can the driver know if torque sleep is active?

Discussion in 'Model S: Driving Dynamics' started by BerTX, Mar 3, 2015.

  1. BerTX

    BerTX Member

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    I don't have a Tesla yet, so I was wondering if there is some instantaneous indication if torque sleep is active on a dual motor Model S.

    My current ICE is a 2000 Honda Insight, which is engineered to run in "lean burn" mode when driving conditions are right. By dropping the fuel mix from standard stoichiometric 14:1 ratio to a 22:1 ratio, the engine efficiency is dramatically increased (MPG jumps from 50 up to 75+). Learning to identify when the car is in lean burn and the art of driving the vehicle to spend as much time as possible in the required conditions can greatly increase fuel economy.

    While it is possible to identify lean burn from performance of the Insight and the MPG instantaneous readout, it isn't easy. Aftermarket means of indicating lean burn were developed by tinkerers (i.e. an idiot light) were developed to make it easier.

    What I'm wondering is whether there is an indication that is clear in a readout somewhere that identifies when torque sleep is active? I have heard owners describe a subtle change in the sound of the motors, and there must be a change in the power consumption readings -- but is it definitive?

    I'm not planning to spend time trying to hypermile my MX when I get it, but I can't help but think there would be times I'd want to stretch the range as much as possible under certain circumstances. I'm thinking that if I can learn to drive my Insight in lean burn, maybe I can learn to drive my MX to optimize torque sleep if I just had a way to know when I was there...
     
  2. benjiejr

    benjiejr Technogeekextraordinaire

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    There is no clear indication on the dash but I think it would be a nice update. When I see my energy consumption graph drop dramatically is when I assume torque sleep is active. If the road noise is low, some say you can hear the front motor more (quiet in the rear).
     
  3. kennybobby

    kennybobby Member

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    #3 kennybobby, Mar 3, 2015
    Last edited: Mar 3, 2015
    Seems to me that the patent describing torque splitting indicates that throttle position and rate are the primary inputs that determine how much torque is requested to be produced. A constant throttle setting with very gradual and slow changes would prolong the minimum energy setting using the most efficient motor torque split.

    In an ICE car cruise control tries to maintain a constant speed and may increase the amplitude and frequency of throttle oscillations more than a hypermiler who knows how to 'coast' up hills, anticipate lights and traffic, etc. i would bet you already have those skills with the insight in lean mode, and they would carry over exactly. kb

    edit: tesla cruise seems to be integrated into the controller and works better than ICE.
     
  4. Cottonwood

    Cottonwood Roadster#433, Model S#S37

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    I don't know, I got 261 Wh/mi on a 242 mile drive with 1,800 feet of net elevation gain in a P85D with .179, crossing 3 mountain passes, one in the snow. I used cruise control except for icy/slushy conditions, stoping, starting, and speed changes, twisty roads, and with other cars around. There were plenty of climbs, descents, etc.

    See P85D Lost power on road, - Page 26 and following posts for more details.
     
  5. billarnett

    billarnett Member

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    A nice way to do this would be split the power meter's bar in two, one for each motor (stacked so the sum looks just like it does today). By looking at where the division between the two is one could easily tell if torque sleep is active.
     
  6. commasign

    commasign Active Member

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    In my Honda Odyssey, a green "Eco" indicator light comes on when the car is cruising "efficiently". Would love if Tesla could do the same. My old Acura TL SH-AWD could also show on the dash where the torque was at any given moment. While kind of gimmicky, it would be nice if Tesla could do this as well.
     
  7. BerTX

    BerTX Member

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    I like all these ideas. It's a little frustrating to know that the data is available, just not able to display. I'd be tempted to put some kind of inductive ammeter on the rear motor to get an indication, but those kinds of things seem so kludgey when you know the information is available, just not deemed important enough.
     
  8. benjiejr

    benjiejr Technogeekextraordinaire

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    WOW! This is quite impressive! I would have never expected this kind of efficiency with the P85D. I'm not getting near that, but all my tests have been short and informal. I have a longer trip planned from San Antonio to Houston next weekend and I'm very curious what kind of numbers I'll get. This is very encouraging.
     
  9. ArtInCT

    ArtInCT Always Learning

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    I agree that an indicator of some type should be incorporated into the central display. The indicator could simply identify if Torque Sleep is ON or OFF. Such an indicator could be used to train drivers in how to achieve and maintain Torque Sleep. I hope TM does this for all dual motor S and X.
     
  10. rdrcrmatt

    rdrcrmatt Member

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    This is exactly what I hoped they would do with them P85D when it came out.. it would be awesome.
     
  11. AmpedRealtor

    AmpedRealtor Active Member

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    Yes, this would be a great feature along with informing us whenever the suspension is lowering or raising itself.
     
  12. sorka

    sorka Active Member

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    I was hopeful that the new software might have improved the P85D range and I kept reading reports from some users that they saw dramatic gains. But after a while, I realized it was the same two users who were having spectacular results and most everyone else saying they didn't see any or very much difference.
     
  13. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    The route you drive and how you drive it makes a big difference in energy consumption. It's not surprising that those who had good numbers before have better numbers after--and vice versa.
     

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