Backwards Brakes?

Discussion in 'Motorsports Chat & Race Preparation' started by Dwight, Jun 12, 2011.

  1. Dwight

    Dwight Racing with the Gods
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    Noticed something odd while watching a pit stop during the Le Mans race. They showed the brake rotors on a car and the slotted rotors were on backwards! The slots were rotating the wrong direction from how they'd be installed on a street car. Is this normal for racing brakes or did a bone tired pit crew just make a mistake? It was one of the GT cars I think. :confused5:
     
  2. KC Jr 54

    KC Jr 54 New Member

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    Slots dont matter in their direction. Only the vents, if directional, matter in their orientation for proper rotation.
     
  3. BThayer23

    BThayer23 Well-Known Member

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    Slots usually don't cross the vents, though. Not sure why they looked backwards. Usually they spin air from inside to outside.
     
  4. ScottinBend

    ScottinBend Space Cowboy
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    Yep.......weird that there would be different designs for this. Powerslots are grooved to run inside to out and most others are from outside to in.

    :confused:
     
  5. BlimeyCabrio

    BlimeyCabrio Oscar Goldman of MINIs
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    ... and ATE's go both ways. :)

    I don't think it makes any difference... they give loose debris scrubbed off the pads and any outgassing (mostly a thing of the past) somewhere to go.. Seems to me the gasses are going to flow from the middle of the braking surface both inward and outward when the pad is covering the slot... more heat = higher pressure... gas flows toward lower pressure... otherwise, there's not going to be a lot of air "flowing" through those slots one way or another... though, if they are backwards, they will make the car slightly less aerodynamic. :smilewinkgrin:
     
  6. minimark

    minimark Well-Known Member

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    .....creating a dreaded rotationally challenged state.... :(


    ;)
     
  7. Dwight

    Dwight Racing with the Gods
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    Which way the slots turn probably doesn't matter as long as you forget about centrifugal force.
     
  8. Redbeard

    Redbeard JCW: because fast is fun!
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    Yeppers. Look at Stop-tech versus EBC rotors. The slotting faces different ways but the vents on the inside of the rotors go the same way.
     
  9. KC Jr 54

    KC Jr 54 New Member

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    Also the 2011 R56 standard brakes that are cross drilled/slotted.... One rotor, used for both sides, but have straight venting vanes.

    This is THE PASSENGER SIDE:

    Photo0208.jpg


    I guess them there BMW/MINI engineers dont care about this supposed "centrifugal force" (aka voodoo magic).
     
  10. BlimeyCabrio

    BlimeyCabrio Oscar Goldman of MINIs
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    I'm looking for a study on the effects of centrifugal force (or centripetal force) on the effectiveness of brake rotor slots, but, alas, I can't find any. :p

    If you have so much debris being scraped off your pads each revolution that one of the "c" forces is a major factor in clearing it out of the slot... then you may have bigger problems... :)
     

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