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Roadster does a 12.7 quarter mile at Infineon

Discussion in 'News' started by graham, Oct 30, 2008.

  1. graham

    graham Active Member

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    From AutoBlog Green:

    Tesla Roadster goes to the drags, does a 12.7 second quarter mile - AutoblogGreen

    tesla_drag.jpg
     
  2. TEG

    TEG TMC Moderator

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    Looks like manufacturer plates. I think that is VP13 we have seen Tesla people driving all over.

    I think at one point it was "the quickest vehicle in the fleet", when it had PEM1.5, but still with a 2 speed. Hopefully now it has full 1.5 with the single speed gearbox, so that the 12.7s 1/4 mile is representative of production cars.
     
  3. TEG

    TEG TMC Moderator

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    By the way, the ABG link takes us back to this story where they said:
    So, didn't 1.5 actually turn out to be air cooled after all? (And wasn't there a cry for liquid cooling on the autobahn extended top speed runs?)

    I am guessing that they thought about liquid cooling the motor for DT1.5, but ended up just adding enhanced air cooling after all.

    I am also guessing that the sedan will have a liquid cooled motor.

    I wonder if DT1.5 has a "larger diameter" motor compared to 1.0...
     
  4. graham

    graham Active Member

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    #4 graham, Nov 3, 2008
    Last edited: Nov 3, 2008
    More on the Tesla Roadster's public drag racing debut - AutoblogGreen

    roadster-infineon-time-slip-300.jpg
     
  5. bobw

    bobw Tesla Reader

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    #5 bobw, Nov 3, 2008
    Last edited: Nov 3, 2008
  6. TEG

    TEG TMC Moderator

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    I would say this is a great news. They managed to better their estimated 12.9s time even with an engineer driving rather than a professional drag racer.
     
  7. donauker

    donauker Member

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    12.7 is good, but what is amazing is that if he would have gotten the reaction time of the driver in the other lane it would have been a 12.1 !!
     
  8. malcolm

    malcolm Active Member

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    One of the comments on Autobloggreen made me laugh;

     
  9. Tdave

    Tdave Member

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    That 1/8 mile time is really excellent, isn't it? Is it correct to subtract the driver reaction time and come up with 7.406 for the car's ability? Is that normal practice? I know little about how these numbers are typically published.

    I did find this page that implies the Roadster stacks up quite favorably against other super cars in the 1/8 mile (0- 660 ft) time:

    0-660 ft Performance Stats

    Compare to 7.406 for the Tesla.
     
  10. graham

    graham Active Member

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    This site: Tesla Roadster achieves 12.7-second 1/4 mile run is reporting:
    I don't see Tesla posting it on their web site. Did they issue a press release? This report is claiming the information came from Tesla itself, and not the Autoblog Green source...
     
  11. dpeilow

    dpeilow Moderator

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    I'm told that unless it is a professional race, drag strips do not count the driver reaction time. So the 12.7 still stands.
     
  12. doug

    doug Administrator / Head Moderator

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  13. TEG

    TEG TMC Moderator

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    “…VP 13, which has powertrain 1.5 and OTHER ENHANCEMENTS under development that we wanted to test…”


    So, VP13 has a “litte extra” that the current production cars don’t have yet?
    I wonder how close in 1/4 mile time it is compared to production models without the enhancements.
     
  14. dpeilow

    dpeilow Moderator

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    Where did I recently read a claim of 0-60 in 3.7?
     
  15. doug

    doug Administrator / Head Moderator

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    I think it was the Web 2.0 interview where Elon said they're working on a 3.7 or even 3.6 second 0 to 60 time with some "power pack enhancements."
     
  16. graham

    graham Active Member

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    I would assume this would mean higher capacity, but fewer cells? (the same or greater power and less weight?) While the electronics and motor have changed, to my knowledge the battery has not changed since 2006 or earlier. Batteries have certainly gotten better since then I would hope...

    I wonder if they are using any new chemistries, or are just fiddling with newer versions of the same batteries?
     
  17. TEG

    TEG TMC Moderator

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    Not necessarily. Performance could improve even if all they did was reduce the weight. Or a different configuration could offer higher current output, but lower capacity.
     
  18. TEG

    TEG TMC Moderator

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    I doubt that. Typically there is nearly equal traction on both rear wheels, so a LSD wouldn't offer any benefit in a straight ahead 'drag'. A limited slip is really only most useful when going around corners and the road surface is uneven (for instance sand on the outside of the corner).
     
  19. GSP

    GSP Member

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    I'm not a fan of most limited slip differential designs, but an electronic locking differential might be a nice upgrade for the Roadster.

    In theory, the traction may be the same for both rear wheels, but in real life the road surface can limit traction for one wheel. With the Roadster's open diff, the traction controller has to limit torque to whatever the one wheel with the least traction can support.

    With a locked differential, all the traction from both wheels can be used.

    However, the Roadster's open diff is just as good or better than a limit slip unit when going around corners. With an open diff, when you apply to much torque the inside rear wheel will spin, but the outside wheel will not. This allows the outside rear wheel to continue to provide the lateral force required to prevent oversteer (spin out).

    With a LSD, torque can be applied to both wheels, requiring more skill to prevent a spin out.

    With a locked diff, both wheels will spin. This instantly reduces the lateral force of both rear tires to zero. A great deal of skill and caution is required to drive a car with a locked diff on public roads.

    The electronic locking differential is the best of both worlds, completely locked for the 0-60 sprint, and completely open for going around corners.

    GSP
     
  20. vfx

    vfx Well-Known Member

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    The torque curve could be adjusted to maximize for 0-60 times.
     

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