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Discussion Starter · #1 ·
I guess nothing is ever easy...just finished rebuilding the front end, and took it in for an alignment yesterday. This is what I was told..hopefully it makes sense:

Camber: Min .50 Nominal 1.00 Max 1.5
Left is 1.2 Right .5

Caster: Min 2.00 Nominal 3.00 Max 4.00
Left is 1.7 Right is 1.2

On camber, he told me to turn the upper ball joint 180 degrees on the right. On caster, the big washer is already in the back of the UCA...so it can't be adjusted anymore. What he told me to do was place 1/4" shims on under the rear bolts where the front end bolts to the frame. This should tilt the front end backward, and provide more caster..then the washers might have to be swapped out to fine tune. Does this sound about right before I dive into this project.
 

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Close Enough

All looks good to me - if it is for a GT.
 

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Discussion Starter · #3 ·
Yes, its for a GT. So is the "looks good" implying I should leave it as is and don't worry about it or the fixes they gave me are good to do.

Thanks.
 

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Dumb!

Just realised that the left/right numbers are your actual measurements....

The right Camber needs to be moved up a bit from .5 to nearer 1.2
Turning the upper ball joint is the only way to alter this so only two possible adjustments can be made. Camber is set at the factory to the smallest possible positive angle. Rotating the flange of the ball jount will increase the posititve angle.

Both Castors need to be nearer 3.0 - certainly above 2.0
 

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Discussion Starter · #5 ·
Thanks. Turning the ball joint will be easy, so the camber can be fixed. Does shiming the rear bolts by 1/4" sound like it will help the castor?
 

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Are you noticing anything unusual in the way your GT drives? Tire wear issues are nearly always a toe-in problem, especially with light weight cars like Opels. If the car is pulling to one side or the other on flat pavement, then the caster needs to be corrected. Since your left and right numbers are nearly the same, I'll bet that the car doesn't pull. Camber is even less important, that's why Opel decided not to have fine adjustment capability (turning the ball joint 180 degrees). For several years, GMC & Chevy trucks had fixed camber settings. Changes required drilling out rivets and replacing parts. No one did this because it just wasn't important enough. If you can correct the Camber by rotating the ball joint, go for it. Of course there's a 50% chance that it will get worse. I would be hesitant to correct caster by using any methods different than designed. (washers on the control arm)
 

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You want your right camber to be 1/4 to 1/2 degree more on the right side. This over-comes road crown, or road camber. If you were to drive on a perfectly flat road (almost non-existant), you may find it pulling to the left slightly.
Also, have them check your camber with YOU in the driver's seat and see what it is.....you want camber to be equal to each other under normal driving conditions EG. if you drive by yourself, measure it with you in the car, if you mostly have a passenger, measure it with both of you in the car........It is (or at least was) common practice for alignment techs (good ones at least) to put 150lbs of weight (usually sand bags) in the driver's seat before putting the sensors on.

Tim
 

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Discussion Starter · #8 ·
Yes, the car drives fairly straight. I can let go of the wheel, and it won't drift at all. The toe-in numbers are pretty close. What does caster do to the drivability of the car??...since these are the numbers which seem way off.
 

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Caster effects the stability of the car and the 'strength' at which the steering wheel centers itself. If the caster number is too low, the vehicle will feel as if it wanders and the steering will not return to center after completing a turn. If the caster is too great, then steering will be difficult (more effort required to turn the steering wheel), and more road feel will be transmitted to the driver. Most cars with very high caster numbers will have power steering as standard equipment (BMW and Mercedes are great examples: look at a mercedes at full lock and notice how far the wheels 'roll over'...this is called caster roll).

Tim
 
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