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Critique my proposed alignment specs

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    Critique my proposed alignment specs

    Car's finally ready for a full-on alignment. Looking forward to it.

    Key specs:
    89 325i
    HR Sport springs / Bilstein sport shocks
    GC "spec E30" camber/caster plates up front
    M3 lollipop bushings
    IE rear camber/toe adjustment kit
    225 Advan r-comps on 15x8 rotas
    The requisite urethane bushings all around
    Most of the interior removed/stripped

    Use:
    Road course (PIR mainly). Higher speed, so stability is the goal. I'm also treating this car as a learn to drive thing, so ease of use is a priority over squeezing the last couple tenths every lap. Basically, I want a fun, easy-to-drive track car. This is NOT, however, as street car, so tire wear is of no concern.

    After reading a few threads here and on bimmeforums, here's what I came up with:

    F. Camber -3.5
    F.Toe 0 (I've read a lot of people using a bit of toe out, but I can't tell if that's for autox or open track use... I figure 0 is a safe place to start)
    F. Caster Maxed

    R. Camber -2
    R. Toe 1/16 - 1/8 in

    So that's where I'm at. At some point, I'll have a pyrometer and do things the right way, but for now I just need a place to start.

    #2
    I ran at PIR last weekend with similar alignment setup. 0 toe in front, -3.5 camber with M3 control arm bushings (max caster), same rear alignment as you listed.

    I basically learned the track over the weekend but I think the alignment settings were good for PIR.

    My car has Ground Control coil over setup with Koni SA shocks and IE sway bars.

    Comment


      #3
      toe in gives a little bit better turn in

      That looks about like mine, mine ATM

      Front
      CAMBER -4
      Caster 10
      Toe 1/8 in (not 100% positive, ill have to look at the sheet)

      REAR
      CAMBER -2
      Toe 1/16 in (again not 100% have to check)

      I hear that if you get rid of the camber in the rear the difference in grip is amazing.

      Not sure if that is true, but id love to hear from some of the guys that have them and if it really does make that much of a difference! I will have my subframe out sometime this summer and if it is worth it ill weld on the adjusters.
      Dan Zickel
      1995 M3, 1991 318iS, 1987 325iS

      Comment


        #4
        Thanks for the feedback. I ended up requesting:
        F. Camber -3.0-3.5
        F. Toe Zero
        F. Caster Max

        R. Camber -2.0-2.5 (exactly one degree difference, front to rear)
        R. Toe 1/8" in


        We'll see how it goes. I have a track day Sunday at a very short/tight course (think autox), so that will be a good time to learn the car and its first-time-ever full alignment.

        Comment


          #5
          Originally posted by E30Driv3R View Post
          toe in gives a little bit better turn in

          That looks about like mine, mine ATM

          Front
          CAMBER -4
          Caster 10
          Toe 1/8 in (not 100% positive, ill have to look at the sheet)

          REAR
          CAMBER -2
          Toe 1/16 in (again not 100% have to check)

          I hear that if you get rid of the camber in the rear the difference in grip is amazing.

          Not sure if that is true, but id love to hear from some of the guys that have them and if it really does make that much of a difference! I will have my subframe out sometime this summer and if it is worth it ill weld on the adjusters.
          I specifically mentioned the rear end kit to the alignment guy...I'll post back if he has any comments. From what I've heard, they offer a pretty good range of adjustment.

          Comment


            #6
            Re. "I hear that if you get rid of the camber in the rear the difference in grip is amazing."

            On high hp cars rear camber is a trade-off between lateral and longitudinal grip. High hp cars can use that longitudinal grip to accelerate hard out of turns. E30's don't have much hp, so there's not much call to minimize rear camber. It's not all that adjustable anyhow, but I wouldn't intentionally reduce it below -2deg.

            In NASA SpecE30 the amount of neg camber we can get is limited by the rules. Most folks are running as much camber as our 20yr old cars will get. With those caveats in mind, the average setup is probably -3F, -2R.

            If I ran -4F and -2R I'd have too much oversteer at high speeds. I'd go flying thru some sweeper at 100mph, the aero affect would make my rear end light, the limited acceleration potential at that speed would reduce my ability to keep weight on the rear, and.....my rear end would try to get out from under me.

            I spun the other month on a fast left-hand sweeper at 96mph. I can't get enough neg camber on my right rear. And I didn't really understand the significance of that until that spin.
            www.Gress.org

            All that is necessary for the triumph of evil, is for good men to do nothing. -E. Burke

            NASA SpecE30 #6, BMWCCA #161
            sigpic

            Comment


              #7
              Originally posted by E30Driv3R View Post
              toe in gives a little bit better turn in
              A little front toe OUT will improve turn-in. Try .03deg.
              www.Gress.org

              All that is necessary for the triumph of evil, is for good men to do nothing. -E. Burke

              NASA SpecE30 #6, BMWCCA #161
              sigpic

              Comment

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