Suspension Brakes 1st Gen Suspension tuning question

Discussion in 'Tuning and Performance' started by davavd, Dec 29, 2011.

  1. davavd

    davavd Club Coordinator

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    BEFORE was a 2006 S convertible with no suspension mods, other than an H-sport 19mm rear sway bar (put on by Way at MOTD) set at the middle holes and Mini Madness polyurethane front control arm bushings. I thought everything seemed right, nicely balanced.

    Recently, I replaced the struts with Koni FSDs. At the same time, I replaced the front swaybar bushings and the rear strut upper bushings with Powerflex polyurethane, and the front upper strut mount plates with Vorschlags. The front camber is -1d40'; toe is .05'. I have been driving it this way for about 2 months.

    It is all much stiffer, to the point where it sometimes seems like something else is clunking, but the ball joints were pronounced OK. Also, I get the feeling I should stiffen up the rear swaybar a little – does this seem like a reasonable thing, given the latest changes?
     
  2. BThayer23

    BThayer23 Well-Known Member

    Jun 12, 2009
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    Vorshlags are noisy over bumps, as they have no rubber or urethane bushing in the upper bearing. But a clunking could be a loose top strut nut. It's difficult to get adequate torque on that nut unless you have special tools or are creative with wrenches.

    Are you still on stock springs?
     
  3. k-huevo

    k-huevo Club Coordinator

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    When FSDs fail, they knock.

    The strut nut may be loose on the camber plate (common), it is possible for the dust seal around the ball to wear or dislodge causing a bit of noise, the spool can wear, and the press-fit parts can also loosen causing noise.

    Convertibles make more noise. Be sure all the underside braces are tight.
     
  4. ScottinBend

    ScottinBend Space Cowboy
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    also.....if anything you may want to reduce the rear sway bar as the camber plates will do more for front grip and cause the car to become loose.
     
  5. Crashton

    Crashton Club Coordinator

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    Tighten that rear bar up & enjoy the ride. :smilewinkgrin:
     
  6. davavd

    davavd Club Coordinator

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    I am glad I asked. How do I back off the bar. I know I need to move the link one hole further out. I think it's ok to do this on one side only, right? I have never changed the bar, since it was installed, so how do I do this?
     
  7. Crashton

    Crashton Club Coordinator

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    If you find that the car handles fine now, why back it off?

    To answer your question yes moving back one hole to the rear will soften the bar. I always have my bar set equally side to side.

    Jack the MINI up. Support it with jack stands. Remove a rear wheel then jack up the control arm to take the load off the sway bar. Then you can remove the link & move it where you wish. Repeat on the other side.
     
  8. k-huevo

    k-huevo Club Coordinator

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    No need to raise the trailing arm with equal length links. Different positions for each side creates pre-load using equal length links (not recommended). With both wheels off, remove the link nuts on the bar, pull the link away, repeat for the opposite side, move to the desired hole, reinstall the nuts.
     
  9. Crashton

    Crashton Club Coordinator

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    Twice a year I do mine that way. If I do not raise the arm with a jack there is a heck of a bind. For me raising the arm is easier. Your mileage may vary.
     
  10. k-huevo

    k-huevo Club Coordinator

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    If you have stock links, the bar is tweaked.
     
  11. davavd

    davavd Club Coordinator

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    As I said in the original post, before the latest changes, everything seemed nicely balanced. Now, after two months with the changes, I still feel something is a little bit off when cornering. Does "jack the Mini up" mean one side at a time, or is it easier if I jack both rears?
     
  12. davavd

    davavd Club Coordinator

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    So does this mean I need to get adjustable links to use a different hole on one side?
     
  13. Crashton

    Crashton Club Coordinator

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    Tweak me up Scottie! :lol:
     
  14. k-huevo

    k-huevo Club Coordinator

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    I don't recommend using different holes with either adjustable or nonadjustable links.

    Adjustable links are useful with corner balancing, and/or on the front with extreme lowering. The vehicle is corner balanced with the links disconnected and weight supported by the wheels, then the links attached with no preload, while the vehicle is still supported by the wheels. This can cause some slight binding when both wheels are at full droop, but it usually is not much.

    Raise both rear wheels to disconnect the swaybar, otherwise there will be a load on the bar, creating a situation where the trailing arm must be raised so the link can be removed. Keep it simple with both rear wheels off the ground.
     
  15. ScottinBend

    ScottinBend Space Cowboy
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    I don't think there is really any problems with using different holes on the sway bar as long as the oem links will fit w/o the need to force them in. My understanding of the in-car adjustable sway bars in race cars is that the adjustment is usually done on a single side.
     
  16. davavd

    davavd Club Coordinator

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    Now I am starting to wonder if it doesn't make more sense to leave the bar alone and maybe back off the camber a little and see if that doesn't restore the "perfect balance". Or maybe just give it some more time and see if I don't get used to the new feel. I don't think I'll do anything until I get new tires and break them in. I do appreciate all the information, though. This suspension dynamics stuff is a complete mystery to me.
     
  17. Crashton

    Crashton Club Coordinator

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    Do you know what your camber numbers are? If you change your camber you change your toe by doing so. If you are handy you can do this yourself. If you are like me it means a trip to the alignment rack.

    Personally I see changing the setting on the rear bar being a whole lot easier & reversible easily if you do not like the results.
     
  18. davavd

    davavd Club Coordinator

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    Camber is -1d40'; toe is 0d05'.
     
  19. quikmni

    quikmni Moderator

    Jun 6, 2009
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    What don't you like about the handling?
    What are the rear alignment settings?
    With adjustable front camber most people run more negative camber than you currently have, usually around -2.0 degrees.
    Since it is a little bit of a pain to jack up both rear tires at the same time, I usually do one side at a time by using two jacks (one to lift car and one to lift arm to remove pre-load) or one jack and a jack stand (jack up car, put on jack stand, then use lack to lift arm to remove pre-load).
    The amount you adjust the rear bar depends on how much negative camber you run if front and rear. With a 19mm bar you can go full stiff without much oversteer concern.
     
  20. davavd

    davavd Club Coordinator

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    I I feel like the car has more body lean than before the camber plates, FSDs, and bushings were installed. I am starting to think that maybe I am just cornering a little faster :biggrin5:. In cornering that is not near the limits, I feel more under-steer than before, which I don't like, but near the limits, I can feel the rear end wanting to rotate more than before. There is a fair chance that the left front knuckle is bent (hit a big pothole, hard, shortly before all the replacements), because the left front camber plate is maxed out.
     

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