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rear suspension

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From what I've read you can alter you're pinion angle by using adjustable lower control arms or an adjustable upper control arm. Is there a preferred method? I would guess that after lowering you would have to shorten the lower control arms to adjust the pinion angle back to within spec. I'm looking to add tubular lower control arms and relocation brackets for my Boss which is lowered about 1.5". I guess the full question would be is, since a non-adjustable arm is cheaper than an adjustable one, which would be the preferred choice for where to have the adjustment at, upper or lower or both? This would be for autocross, open track use.
 
For AutoX, I would look at the rules to make sure either does not bump you into a class you don't want to be in. You might be able to get away with one and not the other. But the springs might already push you into a class that allows them?

Regurgitation of what I have read here:
I think most of the guys here just go with the adjustable upper since the stock one allows A LOT of movement, and also relocation brackets for the lowers to correct the roll steer. And and adjustable panhard bar. The only reason I can think of to use adjustable lowers is if the axle is somehow not perpendicular to the center line of the car.

Here is a thread with some info:
trackmustangsonline.com/index.php?topic=6953.0
 
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The illustration from the link you posted really describes the roll over/understeer really well. Even I can understand it. I guess another way of asking the question, has anyone ever bought a set of adjustable lower control arms and set them at anything other than stock length? From a handling standpoint, is there any reason to do so? If I get an adjustable upper control arm, would there be any additional suspension tuning opportunities from a set of adjustable lower arms, and vice/versa?
 
cp85gt said:
The illustration from the link you posted really describes the roll over/understeer really well. Even I can understand it. I guess another way of asking the question, has anyone ever bought a set of adjustable lower control arms and set them at anything other than stock length? From a handling standpoint, is there any reason to do so? If I get an adjustable upper control arm, would there be any additional suspension tuning opportunities from a set of adjustable lower arms, and vice/versa?

I went with adjustable lowers but didn't use them to change the pinion angle. I did however like having them to change the rear toe, I have heard from a member on here and from Kelly from BMR that a poly UCA should be paired with the Steeda spherical bearing to stop from binding, or get a spherical UCA.
 

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