I took my 1971 Skylark in for an alignment and was told that everything is within specs. The car drives fine but the steering will not return to center 100% after making a turn. Can these specs be improved upon to get the steering to have a bit more positive return to center? I remember driving these cars with basically one finger and being able to let go of the wheel after completing a turn and the car would straighten itself out - the steering would return to center. All of my front end components including the steering box have been replaced.
http://www.vikingspeedshop.com/suspension-101-camber-caster-and-toe/ Digging back into the memory banks, I'm pretty sure that's a result of negative caster. But I also think you want it that way... -BC
What were the specs? Unfortunately you will have negative camber on the A-body frame. There are lots of ways to get rid of this but it usually involves changing the upper a-arm. This does not affect return to center that much though. The next problem is it is hard to get positive caster. That is the one you want to give the return to center feel. When they designed the a-bodies power steering was an option. Therefore in order to reduce steering effort the front end was designed with very little caster, maybe a degree or 1 1/2 degree at max. Again the only way to change this is with new upper a-arms or relocation of a-arm mounting point. Toe is pretty straight forward. You will want 1/8 to 1/4 toe in. !/4 is a lot but may help you out. Might try 3/16 and see how it works.
Why is the (Modified Specification) being shown? I have had guys change the spec to make everything appear to be within spec, and this shows on the final print out. Have they made any adjustments? Is this the before alignment or after? Looks like they were trying to make a "toe n go" alignment. Shims can be added to the upper mounts to correct caster and camber. I have not had any of my GS's not be able to make specification. What condition are your bushings? When they are worn this will affect caster and camber and the ability to adjust.
These could be considered after specs. The same shop did the alignment 3-4 years ago when I had all the front end parts (ball joints, control arm bushings, tie rod ends etc...) replaced. Nothing was done to the car this time. I have no idea why "modified specs" are being shown. I might have 2000 miles on the front end parts. What would you change to improve things?
The modified spec shows up if you change the specs or the tolerances. IE adjust the spec to the car the spec to the car not adjust the car to meet spec. How many shims are in each of the upper "A" arms? This is where the adjustments are made.
First picture is the drivers side, there are two thick and one thin shim at the rear, two thick and two thin shims at the front. The passenger side has one thick and one thin shim at each if I am not mistaken.
Specs for the late 60s and early 70s sucked royally. I'd want the passengers side to get closer to the left side specs. Personally, I like as much positive caster as I can get and -1 camber. You can get these cars driving really well with a little effort and some know how.
Personally I want as much POSITIVE caster as I can get. On the A-Body's + 2-3 is very possible. On camber for street driving I try to maintain between ZERO & -1 negative. For toe I normally split the diff. between minimum & maximum. Works well for me.
Lee, I`m assuming you have power steering? If your alignment specs are in order you might want to check that your steering column is not too tight. If it is, as was the case in one of my cars after the PO "restored" the column, the tight column will not allow the "torque rod" in the steering box to relax and stop boosting the steering which allows the geometry of the front end to return the wheel to a straight ahead position. Tom Mooney
Also, just need to make sure that you haven't recently installed headers which might be close to the steering column
I recently installed a rebuilt steering box from Hector and noticed a great deal of improvement in the "looseness" or ease of steering. I'll look into the steering column too. From what some of the others have said it looks like I need to improve upon my current alignment specs to get that "Buick" feel back in the steering. I want to be able to turn a corner and let go of the wheel and have the steering center itself. It's almost there now, just not 100%. Stock manifolds - no headers.
That alignment can and should be improved upon - cross camber is way out and although the factor caster spec is what it is, getting as much POSITIVE caster as possible always improves steering feedback esp at highway speeds. Shoot for 0-1 degree negative camber, as much positive caster as possible, and make sure they are less than 1/2 degree different from side to side. Toe is good. Doesn't even look like shims were touched. Not sure why shops make this so difficult.
