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Thread: Front Alignment

  1. #1
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    Front Alignment

    Okay, time to get serious on the GTM.
    I set the front suspension adjusters to the mid (neutral) position and I have about 1 1/2 degrees more caster on the left than the right. Left 1 1/2 deg, right 0 degrees. Is this common on a Gen I? Camber is nearly equal side to side, close to 0 degrees.
    As noted on other posts, I plan to relocate the upper control arm mounting tabs to get more caster but assumed that each side needed to be moved the same amount. Nothing looks molested but I did buy the kit second hand with some work done. I do not have any history on the upper control arms. Any suggestions?
    Ken

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    Senior Member beeman's Avatar
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    One thing I have always been confused about is whether the gen1 guys were moving their control arm mounts 1.in order to increase the available caster for the sake of increasing caster or 2.in order to get the caster they want without pushing the wheel too far forward in the wheel well, thus avoiding fiberglass work.
    MK3.1 2004 Mach 1 donor. ABS, PS, TC.
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  3. #3
    Senior Member Roger Reid's Avatar
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    We Gen I guys moved the upper control arms back to gain more caster without sacrificing camber. In a Gen I, the process is to move the lower rear mount all the way out (moving the wheel forward), then adjust the front lower mount to get .5 degrees negative camber and live with whatever caster you wind up with (usually less than -1 degree). Crash's shim adjusters will allow for more adjustment range so those are helpful. My finished numbers are close to 1.5 degrees negative camber with negative 5 degrees caster after moving my upper mounts rearward.
    Just an old man with a great hobby

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    Thanks Roger. My concern is whether the frame would be off that much or if the control arms could be bad or the wrong parts. Other posts mention moving the mounts back 1" for additional caster. Do I move the right back a little more to be able to set them equal?
    Ken

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    All, I just discovered that I have 2 left upper control arms! The mounting bars have an "F" and "R" stamped on them. The right one had the F in the rear and R in the front. When I measure, the correct arm puts the upper ball joint about 1/4" to the rear of center. With a left arm on the right, this moves the ball joint 1/2" forward of it's correct location, causing the caster to be off about 1 1/2 degrees and maintaining the correct camber.
    Rockauto has Dorman and Mevotech brands. Anyone have any experience with those brands of control arms? I have found Dorman okay on misc small parts but I don't have any experience with them on major assemblies.
    Thanks for any help.
    Ken

  6. #6
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    All,
    The Dorman right UCA arrived and looks like a decent piece. The mounting bars are rotated 90 degrees off. Do you just grab them and twist to the correct orientation? I want to avoid tearing the bushings if some technique is needed.
    Thanks
    Ken

  7. #7
    Member eseethal's Avatar
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    Yes, you just twist them to the right orientation. The warmer they are, the easier it is to do.
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    Thanks

  9. #9
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    Roger,
    I set the alignment as you suggested, rear adjuster out for max caster and then set camber to - 1/2 degree with the front adjuster. I ended up with about 2 degres of caster. Thanks for the tip on how to align.
    I did move the inner attachment points of the upper control arms down. It resulted in some bumpsteer but I have the kit to try to remedy. I have put taller ball joints on MII type suspensions and cured the bumpsteer with a similar kit. We will see if it works on the GTM.
    Ken

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