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Model S aerodynamic enhancement - does it make a real world difference?

Discussion in 'Model S: Driving Dynamics' started by Chris_WDO, Jun 22, 2015.

  1. Chris_WDO

    Chris_WDO Member

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    Hi Tesla owners!

    I am contemplating having a Modesta Treatment for my Tesla Models S, and I've come across the very good Modesta Coatings. One of them, the Modesta BC-05 claims to make a difference in aerodynamic drag by getting cd -0.02 or 5 km/h (approx 3mph).

    What I wanted to know is: is there one owner here who has the Modesta BC-05 layer on his Model S' skin?

    And if yes, is there any noticable difference in range or energy consumption at a given straight line and level highway speed? (of course wind could make the comparison difficult). However, if it really works and reduces the already low cd of 0.24 of the Model S to an even better cd 0.22, this should definitely make a difference in Range on a long road trip with constant highway speed.

    Here's what I've learned directly from Modesta:
    7v6Rvl.jpg

    Just curious because there is a similar effect known with the skin of sharks, which makes them have less drag at higher speeds, and a little bit more drag at low speeds than a perfectly even surface.
     
  2. Johan

    Johan Took a TSLA bear test. Came back negative.

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    If you do try this please document your average Wh/mile before and after the procedure. And try not to drive more economically afterwards which would obfuscate the data.
     
  3. gordo

    gordo Member

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    My guess is that this could be true under very specific laboratory conditions, but I'm also going to guess that in the real-world the advantages will be diminished by the fact that:

    * the surface of your car will quickly become covered with the same dusting of exhaust soot plaguing every other car on the road, so the surface you're actually offering the wind is really not all that different.
    * it's not clear that a simple freshly waxed body doesn't effectively offer practically the same or similar advantages as this coating

    If you want to affect the Cd in a real measruable way, figure out a way to remove the side mirrors (replace with cameras? -- probably illegal) and/or get some sort of aero wheel or else fashion a wheel gap cover.
     
  4. kenkamm

    kenkamm Member

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    This doesn't pass the common sense test IMO. If a relatively cheap coating like this makes that much of a difference, every car maker would already be doing it. The things automakers are doing for 0.1 MPG improvements are amazing. Fudging graphs like that is all too easy, so they simply can't be trusted.
     
  5. Todd Burch

    Todd Burch Electron Pilot

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    Agree totally. Might be true for a perfectly clean car, but within 10 miles your Cd will be back to what it was before. Real-world benefit? Almost nil.

    Marketing at it's best!
     
  6. BerTX

    BerTX Member

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    #6 BerTX, Jun 23, 2015
    Last edited: Jun 23, 2015
    I think the product name actually translated to "hogwash", but they felt Modesta was more marketable.

    As far as I know, the amount of difference in CD between a clean car and a dirty car is not measurable. I'm dubious that any surface treatment would make a difference. I'm no expert, but doesn't surface drag make up a fairly insignificant part of the equation?
     
  7. Bangor Bob

    Bangor Bob Member

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    Totally off topic of me, but it's useless thread anyway... I find it amazing the amount of easily picked low-hanging fruit the automakers AREN'T bothering with to find MPG improvements, especially on trucks. Dumb crap like ginormous square fronts on their pickups. Axles, diffs, exhaust and suspension hanging in the underbody breeze. Giant wheel arches with big fender flares, huge tow mirrors, etc. Even simple stuff like not tucking the windshield wipers down under cowling...

    Maybe they try, and they certainly moan a lot whenever new fuel-economy regs are proposed, but the stylists and market-research types are still allowed to come in and undo 3/4 of the work the aerodynamicists did, so I don't think they're actually trying that HARD. Or maybe top management doesn't quite understand vehicle physics and are asking the powertrain department to hit the economy targets all on their own.

    [ / soapbox ]
     
  8. swaltner

    swaltner Member

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    I'll keep it family friendly and call this hogwash as well. I wouldn't spend any money on it.
     
  9. Johan

    Johan Took a TSLA bear test. Came back negative.

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