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Old 07-04-2010, 09:44 AM
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Brian Martin,Freelance adviser
 
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Alignment of collision damaged cars is one of my "things". I have to say there is no set amount of anything on the amount of shims, the thickness of shims and the placement of shims on a 45 year old car, toss everything out the window.

You put the gauges on the car, and align it. What you end up with could be five 1/16" shims on one side and two on the other in the back and a 1/32" on the front of one side and none on the other. These shims from the factory were making up for less than perfect placement of control arm mounting points. Today, after 45 years of hitting pot holes and frame sag, it is anyones guess what you will come up with, and it doesn't matter one bit, as long as the friggin wheels are where they need to be! A TINY bend in a control arm, one that you would NEVER SEE looking at it could send you off a mile. That is what the shims are for.

There is no way you can set anything without having ALL the weight in the car, the motor, the body, all the way to the front bumper.

If you are looking at your negative camber now you have no springs in it and the frame is sitting below ride height so OF COURSE you will have negative camber. Look at the upper control arms and how they are leaning? At proper ride height they are near level. The further from level they are the "shorter" they are. Meaning that the ball joint comes in towards the frame as the control arm arcs up or down. This isn't as pronounced on this car as a newer one as this car doesn't have a lot of the geomotry engineered into it as a later model car does, but you still get some negative camber on this car as the outside wheel goes up around a corner when the car leans. On a newer car this is really clear, as the car goes around a corner and the body leans, the outside tire going up into the body, right? Well, when this happens the top of the wheel goes in creating MORE negative camber giving the tire more "bite". Stand with your legs straight down, then lean your body to one side, if you put your foot out further away from the other one you can lean more, right? The negative camber being increased does this. So it is designed into your suspension to do this, the lower you have it the more negative camber. By the way, this is what the "long spindle" modification does for you. On a first gen Camaro this is one of the first improvements you make if you want to make it handle better. You put a longer spindle in it, this raises the upper control arm which in turn gives you a "head start" on the negative camber needed in the corner. Once the car leans that upper ball joint moves in quick brings the top of the tire in giving it more bite on the corner.


Forget about it until you get it up at right height. There is NOTHING you can do with your alignment with the car down like that. EVERY adjustable point, camber, caster, and toe will ALL be changed when the car is raised up.

As Bryan said, they also make offset upper control arm shafts for a lot of cars (don't know about yours) to correct alignment issues that shims alone can't.

Brian

Last edited by MARTINSR; 07-04-2010 at 09:58 AM.
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