someone help me with wheel offsets

Discussion in 'OT Driven' started by Peter O'Hanraha-hanrahan, Feb 19, 2004.

  1. Peter O'Hanraha-hanrahan

    Peter O'Hanraha-hanrahan OT Supporter

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    i'm having a hard time understanding them:hs:
    for a stock S4 the offset is usually like ET30 or ET35, but for my widebody its been reccomened by multiple people to me that I get like ET19 or something around that. How would a smaller offset make the wheel fit with a wider fender? It would make sense that more offset means the wheel will be further away from the mouting point, but it seems like less offset means the wheel will be further from the mounting point.
    can anyone explain this to me clearly, becuase i know i dont get it at all :wtc:
     
  2. DSHR

    DSHR Well-Known Member

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    If you didn't get a wheel with a lower ET your wheels wouldn't be flush your body.

    And your correct the lower the ET the further from the wheel mounting point.

    You could get away from using a custom wheel and use some spacers :dunno:
     
  3. MerkurMan

    MerkurMan Gimme Nuts, Bolts and 12 Volts

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    Because offset numbers are in negative. So -19 is further from the wheel hub than -30.
     
  4. Peter O'Hanraha-hanrahan

    Peter O'Hanraha-hanrahan OT Supporter

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    that makes sense. thanks
     
  5. MaRcH HaRe

    MaRcH HaRe New Member

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    You guys dont really understand offsets :o

    No they arent. They are positive, zero and negative.

    Deep dish = Negative.
    Shallow dish = Positive.

    The offset is measured in mm, it is measured from the centerline of the wheel, to the flange on the hub (where the wheel mounts). The difference between the offsets is listed below.

    [​IMG]
    *The side facing away from the stub axle is to the right, i.e the side facing away from the car*

    A positive offset means that the centerline of the wheel is to the left of the flange on the hub. This gives you a shallow dish as there is less distance from the flange to the outside of the wheel.

    A zero offset means that the centerline of the wheel is in line with the flange on the hub. This is pretty netural. Not a great deal of vehicles use zero offsets.

    A negative offset means that the centerline of the wheel is to the right of the flange on the hub. This gives you a deeper dish as there is a futher distance from the flange to the outside of the wheel.

    Offsets depend totally on the car, it could be positive, negative or zero. If you change to an offset that isnt reccomended for your vehicle, you run the risk of placing excess stress on components like boil joints (because the load has shifted) which leads to premature failure of components.

    Make sense now?
     
    Last edited: Feb 20, 2004
  6. Peter O'Hanraha-hanrahan

    Peter O'Hanraha-hanrahan OT Supporter

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    i read that already it doesnt help me understand how a wheel with ET20 better fits a wider fender than a wheel with ET35, which would be like 1" inside the fender
     
  7. MaRcH HaRe

    MaRcH HaRe New Member

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    It doesnt Fit better. They have worked out a thing called SAI and found it to be the optimum point. It doesnt so much have something todo with fitting under panels, it's steering and suspension geometry. Fit anything you want, as long as you get it checked over by someone who knows what they are doing. Over here, you have 2 major problems, one is loading ball joints, if you start to fuck around with offsets you can upset things putting more load on the hub, wrecking bearings and ball joints. The other problem is increasing or decreasing track. We have limits as to how much you can change a vehicles track by, changing your offset which shifts the wheel centerline alters the track just like fitting a wider wheel does.
     
  8. Dentite

    Dentite Guest

    The offsets in this case are positive, +20, +35. +20 will stick out 15mm more than +35 in a given wheel width.
     

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