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Bent front thrust arm?

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Old 03-30-2009, 09:02 PM
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va122
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Default Bent front thrust arm?

Hey,

I just got an alignment done and they told me that I couldn't get less then 3.5 deg of camber on front right. The other side is holding fine at 2.6 per my preference. I watched them for hours trying to get the right side correct and couldn't do it. They said this happened to another car and turns out the thrust arm was bent and when they replaced it they got the camber where they wanted it with no problems.

Has anyone heard of this or is it crap?

I get my camber from rotation of the strut tops not shims.
Old 03-31-2009, 01:12 PM
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XLR8N-FAN
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I suspect that "catching air" on Banner grade had something to do with the bent arm.
Old 03-31-2009, 01:13 PM
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I rotated my strut tops and on the RHS the LEAST amount of camber I can get is -2.8. On the left they could get -2.5 so I went with -2.8 on both sides. I can't really see how the thrust arm would affect the camber that much. You would think that the caster would be really different side to side if the thrust arm was bent. You might have to elongate the holes on the strut top.
Old 03-31-2009, 01:22 PM
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What shim(s) is/are installed?
Old 03-31-2009, 03:43 PM
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va122
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Caster is a slight issue too I'm a 8 deg both sides. I prefer 8.5 and had up to 9 so i'm not sure where the problem lies.

I have the notch in the strut tops already, from when I had this much camber before.

There is a shim on the RHS tie rod, but strangely there is none on the LHS.

I'm so confused.

And yes martin, catching air MAY have something to do with it. So I'll send you a bill vs giving you hoosiers.
Old 03-31-2009, 04:03 PM
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KOAN
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If you have a shim on the right, and you have too much - camber on the right, why don't you remove the shim? Are you referring to the shims in the control arm?
Old 03-31-2009, 05:18 PM
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control arm, sorry.
Old 03-31-2009, 06:55 PM
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KOAN
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Well, the shim is added to give more neg camber, so if the shim is on the side with too much, that would be one place to start.
Old 03-31-2009, 07:25 PM
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va122
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Unfortunately its the opposite situation.

I wonder if i should rotate the struts back and add shims to get the camber I want. It will shoot my castor up but my monoballs are adjustable for castor.

Ideas?
Old 03-31-2009, 07:34 PM
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Originally Posted by va122
And yes martin, catching air MAY have something to do with it. So I'll send you a bill vs giving you hoosiers.
Don't blame me if a 3/4 cup car has trouble keeping up with a stock Z06.
That day was like an episode of "Dukes of Hazard" complete with sheriff
Old 03-31-2009, 07:42 PM
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My car has no business on the street in its present configuration. I could have used a skid plate that day.

Ok Martin, next time we're on track, both of us on hoosiers and see what happens. Actually you can be on anything you want but I'll be on hoosiers.
Old 03-31-2009, 07:52 PM
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Your car is way beyond what street tires can handle. It's cruel to watch those PS2s cry in pain. BTW, have you seen this video with your buddy Saffronas?
http://videos.streetfire.net/video/H...-Vs_165902.htm
Old 03-31-2009, 08:16 PM
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Ohhhh yea I remember this, with sammy. I rode with Sammy at o'fest cal speedway he was sideways the whole lap. Amazing car control. He was a test driver before the drift scene.
Old 03-31-2009, 08:26 PM
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Stop Hijacking my thread Martin!
Old 03-31-2009, 09:47 PM
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Vic,

If your car is lowered, and the strut tops rotated, camber should be between -2.5 to -3.5 degrees.

A difference from 0.3 degress camber or less between sides locking the strut tops at the same location is normal. Adding 7mm of shims to the lower control arm increases 1 degree of camber, and increase about 0.3 degrees of caster.

Some shops use shims to adjust caster, and get the camber even with the strut tops. If you use rotating metal bushings, you can dial camber and caster with them + shims + strut tops.

The bent trust arm is a possibility, the lower control arms rarely bend they crack, but the trust arms can bend.

By the way, you want -3.5 on the front and -3.0 on the rear given your dedicated track/autoX. -2.5 is for street drivers with shared track/autoX use (like me, well not anymore).

I prefer to use the same size shims on both sides and use the metal center hole bushing instead of the adjustable one. This way caster may read different between sides, but even brand new cars have different caster reading L/R. Running uneven lower control arm lengths (due to different size shims) brings a new game of trust angles messed up between front and rear axle.


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