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Limited slip?

Discussion in 'Roadster' started by Pantera Dude, Dec 28, 2013.

  1. Pantera Dude

    Pantera Dude Member

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    I am under the impression that the Roadster does not have a limited slip differential/transaxle, is that correct? If so, why not?
     
  2. GSP

    GSP Member

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    I believe that the roadster has an open differential, and that it has been documented here on TMC.

    Of course, I don't know why, but with all the trials and tribulations Tesla has just to get a working transaxle, first with Xtrac, then Magna, before Borg Warner stepped in and saved their bacon, I doubt there was any time to consider enhancements like limited slip or computer controlled diff lock.

    I would be careful about retrofitting a limited slip as well, due to the tendency to induce oversteer.

    GSP
     
  3. Doug_G

    Doug_G Lead Moderator

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    Both the Roadster and Model S have an open differential (the Model S is just an enlarged version of essentially the same design).
     
  4. hcsharp

    hcsharp Active Member

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    In addition to the reasons mentioned (no time with pre-Borg Warner problems, worse understeer) it would also reduce range. Would really be nice to turn it on temporarily in certain snow/ice conditions.
     
  5. lolachampcar

    lolachampcar Active Member

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    It seems MS is using one caliper to control single wheel spin. It is not elegant and it does dissipate power to a brake rotor but it stops the one wheel from lighting up and taking all the available torque.
     
  6. dhrivnak

    dhrivnak Active Member

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    I think the goal is to have the most available traction, how that is obtained should be irrelevant. To that end I find the Roadster has the best traction of any car I have driven. There is no wheel spin with several runs at "Street Fights" (Open runs down Bristol's Thundervalley drag-strip NO-ONE has come close to the launch of the Roadster. If someone in a modified car beats me it is at the very end of the 1/4 mile. Why mess with perfection, or at least very, very good.
     
  7. Pantera Dude

    Pantera Dude Member

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    I agree that there doesn't seem to be much need for limited slip in the Roadster. The only time I get wheel spin in the dry is if I am really trying, on a sharp right turn from a standing/rolling start. I was surprised that a car that would do 0-60 in 3.9 seconds didn't spin the wheels. I guess with a manual trans and clutch that would have been a different story?

    - - - Updated - - -

    Thank you guys for all the info!
     
  8. Doug_G

    Doug_G Lead Moderator

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    The combination of smooth power delivery and somewhat-sticky tires is probably the reason. If you have to pause to switch gears then you need that much more instantaneous torque to achieve the same overall acceleration.
     

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