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  • #16
    Originally posted by d2a4 View Post
    Very interest, any pics? I am about to put on a limited solution (KMAC kit). I don't to ruin a set of 18" as they are pricey
    don't want to hijack this thread, will PM you


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    Originally posted by ///Mflossin View Post
    Showed me that it's important to get an alignment IMMEDIATELY after doing any suspension work up front.

    I think I got a bit confused here with the wording and thought Mflossin is talking about FRONT setup.
    (but I still can work out what immediatley AFTER work up front means....:taz

    apologise if this has caused some confusion.
    Last edited by UweM3; 03-10-2008, 07:52 AM. Reason: Automerged Doublepost


    Goodbye M3, you served me well.

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    • #17
      Originally posted by Ironhead View Post
      There is some tread on the tires left, yet the inner edges are worn to the belts. I had not really noticed because that portion is kind of hard to see when the car is on the ground....

      The Kmacs are adjusted for minimum negative camber (at least they "were"...who knows where they have wandered to).

      So I need a way to remove some negative camber.....

      I am aware of the IE kit, which would definitely be a relatively cheap solution.

      I like the rod end adustable toe, but the camber adjusts simply via a slotted bolt hole in the subframe,
      my bet is the Kmacs have slipped. they don't grip well at all. Bimmerworld also sells the IE kit, so that's an option if your problem is interfacing with IE directly

      as for your desire to remove negative camber, why? camber is rarely the issue with inside tire wear like you have, it's toe-in that causes it. if you can add just toe-out and leave your negative camber, you'll see your tire wear go down noticably.
      James
      sigpic

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      • #18
        Originally posted by jht3 View Post
        my bet is the Kmacs have slipped. they don't grip well at all. Bimmerworld also sells the IE kit, so that's an option if your problem is interfacing with IE directly

        as for your desire to remove negative camber, why? camber is rarely the issue with inside tire wear like you have, it's toe-in that causes it. if you can add just toe-out and leave your negative camber, you'll see your tire wear go down noticably.

        I agree, when I say "camber" I certainly need to include the possibility of screwed up toe settings. My main point is that I am not even going to try to adjust the Kmacs again. I am looking for a permanent solution.

        The Kmacs were really cheesy. Even when I put them in, I knew they would not be a permanent solution. Just buying me time.....

        What rear toe settings are most of you using? When last I adjusted it, I had "zero", but again that may have wandered.

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        • #19
          I had serious tire wear with properly set toe. If you drive hard and barely spinning the tires exiting corners, the inside shoulder gets chewed up fast. Now I run the same toe-in as before but with 2 degrees less camber, and the wear is totally fine...
          Anders

          "Objects in mirror are losing..."

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          • #20
            I had these fabed up by TC Design. I'm using the IE camber/toe kit with this setup.




            -jonathan
            '07 E86 M Coupe Interlagos (Daily Driver)
            '91 E30 M3 Alpine White (Track car)

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            • #21
              Originally posted by Jonathan B View Post
              I had these fabed up by TC Design. I'm using the IE camber/toe kit with this setup.
              nice. i was talking to RRT about something similar this past weekend.
              James
              sigpic

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              • #22
                Originally posted by Jonathan B View Post
                I had these fabed up by TC Design. I'm using the IE camber/toe kit with this setup.
                That looks like a really good setup...

                Just a question. Why did you chose not to incorporate the camber/toe adjustment into the rod end bearings? Ease of adjustment? Removing the trailing arms to adjust camber or toe would be an unacceptable PITA. I saw a DTM design somewhere that had the rod end (used for toe adjustment) mounted with a turnbuckle of sorts between it and the trailing arm. So to change adjustment, you did not need to turn (and thus remove) the rod end. You could just turn the turnbuckle.....

                I know there is a "theoretical" problem with the IE eccentric bolt solution, as it changes the role center. I only know this cuz Gustave said so. My question is, in the real world, is there the slightest chance that in anything short of DTM any of us will notice any negative effect? I know on the later DTM trailing arms they went to lengths to design the arms so all adjustment was done by moving the positions of the rod ends relative to the arm, rather than moving the pivot point. So I know at some level this becomes relevant, but is it for us "mortals"? I am thinking not.......

                I could go crazy with this, chasing the "ultimate" solution. It happened to Gustave. He went crazy and sold his car. Or maybe he suddenly became sane and sold his car.....:idea::p:


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                Originally posted by jht3 View Post
                nice. i was talking to RRT about something similar this past weekend.
                I keep going to the RRT site looking for cool modifed parts that we could all use. Nothing ever really seems to appear........:(
                Last edited by Ironhead; 03-10-2008, 04:53 PM. Reason: Automerged Doublepost

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                • #23
                  Originally posted by Ironhead View Post
                  I keep going to the RRT site looking for cool modifed parts that we could all use. Nothing ever really seems to appear........:(
                  yea, the site isn't all that for window shopping. barry and james both stay on top of the forums on www.rrtsuspension.com, so posting up there may get you something
                  James
                  sigpic

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                  • #24
                    Well, I just finished putting the car back together with the IE eccentric bolt camber/toe adjustments installed. I also used Powerflex trailing arm bushings on the reassembly. I didn't bother with photos, since this has been done several times before.

                    Here are my thoughts to anyone contemplating doing this.

                    Dropping the entire subframe assembly (with trailing arms, driveshafts, wheels, and diff still installed) is a hell of a lot easier than taking it all apart and bringing it down piece by piece. I have done it both ways. You just need a cheap Harbor Freight scissors style tranny jack to lower the assembly.

                    Grinding out (elongating) the bolt holes in the subframe is a little bit of a PITA, because it is hard to get an ideal angle for the die grinder. Parts of the subframe get in the way. I was using an electric grinder, if you had access to an air grinder that would help, as they are much smaller. I carefully positioned the plates before grinding, welded them, then used the adjustment plates as a template to enlarge the subframe holes. I think that is probably the easiest way to do it. Make sure you position the camber correction plates all the way "UP" when you weld them in. If you center them, you will not be happy with the amount of available correction. I just plagerized this from elsewhere, but it needs to be repeated!

                    Getting the trailing arms back in with the Powerflex bushings installed was a moderate PITA. The bushings protrude too far out, and you have to sort of force them back in. A thin putty knife (used as a shoehorn), a rubber hammer, and a lot of swearing did the trick. Make sure you thoroughly lube the bushings with teflon grease. I adjusted the eccentric bolts where I "guessed" I would want them, and tightened them down before installing the subframe back in the car. This turned out to be an important move.....

                    Once back in the car, I found it was pretty much impossible to access the tightening nuts on the outside of the toe correction bolts. I am using Powerflex subframe bushings, which have sort of a "hood" that goes over the top of the bushing. This jams up agains the tightening nut, and I did not have a wrench that would fit in there. With a lot of grinding (both on wrenches and on the subframe bushings) I might have been able to get one to fit, but it would not be easy. This, IMHO, is the only significant problem with using these bolts on the E30M3. There is just no room there....

                    However, to get around this, I found that I could put a long box wrench on the adjusting bolt head, and still get the bolts to turn for adjustment even though the nuts were tightened down. And, doing so does not further tighten or loosen the nuts. They just turn with the bolt. Getting a wrench on the bolt heads is no problem at all. There is more than adequate room.... I wound up doing all my camber/toe adjustments without even loosening the nuts. You just have to really crank on the wrench.

                    As sort of a tangent, if you have never made these adjustments in the garage with alignment strings, a jack, and jackstands, you have no idea what a PITA you are missing. Here is the sequence:

                    Take countless measurements to get the alignment strings set up perfectly.

                    Measure toe.

                    Measure camber.

                    Jack up car to make adjustments.

                    Position jackstands so the car does not fall on your dumb ass.

                    Guesstimate corrections with new eccentric bolts.

                    Remove jackstands and lower car to floor. Bounce car to settle suspension.

                    Since you bounced the car, and bumped the alignment strings with your head/foot/jack/jackstands, take countless measurements to get the alignment strings set up perfectly (again).......:shit::music:

                    Measure toe and camber, only to find you are still way off.....:rolleyes:

                    Anyway, after about six cycles of this, I wound up with no rear toe, and roughly 1.5 degrees negative camber in the rear.... That is approxmately where I wanted to be, but I found that on my car 1.5 negative was the minimum rear camber the eccentric bolt system would allow me to have. That is compared with the roughly negative 3 that I had with the KMAC bushings, that was destroying my rear tires. Anders mentioned he got down to roughly -.75, but I could not do that on my car.....I ran out of adjustment at -1.5.

                    I finished with the dabs of nail polish to watch the bolts for signs of rotating out of adjustment. If that happens....not sure what I will do.....:fire:

                    Seriously, if this setup does not stay in adjustment, my next step (after leaving inpatient psych treatment) will probably be to get a pair of used trailing arms and come up with an "ultimate" solution using rod end bearings and some sort of copied DTM design.

                    Sorry for the long winded rant.....:boring:

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                    • #25
                      Nice write up! I still kick myself for not maximizing camber adjustability when I had mine installed. Hmm... may require a revisit some day.

                      Cheers,
                      Jake

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                      • #26
                        Thanks for the write-up Ironhead. Been working on the car a bit lately eh?

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                        • #27
                          Originally posted by ///Mflossin View Post
                          Thanks for the write-up Ironhead. Been working on the car a bit lately eh?
                          Yeah, I'm outta control. It is getting pretty squared away though. You know the drill....two steps forward, one step back.....

                          I needed to get this done to put some decent tires on the car, and not have them torn up in a few K miles.....

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                          • #28
                            nice write up. I did the same install a few months back on my track car e30 and after 8-9 track days this year (driven hard, I'm no sissy!) I've noticed zero movement in the rear setup. I used a paint marker for reference points and a quick check either between sessions or after track days shows them to be right on. The alignment shop said adjusting them was easy too and didn't take nearly as long as they thought it would.

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                            • #29
                              Good info. but I think if you can get ahold of John Mason he may be of some assistance as he has helped Gustave fab parts in the past... With your detailed info. I'm sure he can make your ultimate setup... I will try to locate his contact info.
                              Rich!

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                              • #30
                                Hey dudes......

                                I am trying to figure out a source for these thingys. (thanks Booker for the pics I "borrowed") They are used on the DTM trailing arms to allow a rod end to adjust for camber and toe without being unbolted and "turned".

                                Does anyone know if they are a BMW Motorsport specific part, or a generic item used in other motorsport venues?

                                Thanks!




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