Wheel alignment?

[jbonifas]

OK, it has been awhile, but I am resurrecting this topic again. I am still trying to get this thing from pulling to the right. The most recent alignment yoko couldn't get it either! (The right tire is 1/2" towards the rear of the car as compared to the left side. Also, there are no shims in the front of the right side and 6 in the rear.) The frame is not bent/ got it checked out. It appears that the upper control arm on the passanger side is bent as well as the spring may not be seated. I have always wondered about the springs, they are compressed to the point of several of the coils touching each other and making a metal on metal squeek. Anyway, I am replacing the front springs and upper control arm.
He also wondered how you may adjust the rear wheels. I am not sure if it is camber or caster, but the rear right needs to be adjusted. Help me if you can.
JCB

 

[DDLS3]

Jeff,

Sorry to hear about your damaged control arm, sounds like you have found the culprit. The rear wheel chamber is changed by rotating the the chamber bolt and cam. If you look under the back of your car you will see the strut rod connected to the lowest point of the rear spindle assembly. The other end is connected back toward the middle of the car near the spring mount. On that end you will see a bolthead and cam with graduation marks on it. Loosen the nut on the side towards the front of the car so that the chamber bolt can be rotated. This causes the bottom of the spindle assembly to move in or out depending on which way you move the cam. For a daily driver the rear chamber should be set to 0 degrees negative.

 

[Stingray6974]

JCB,
Before you take anything apart you need to take some measurements. Find an equal point on each side of the frame, trans crossmember bolts,etc. Measure from the grease fitting on the lower ball joint to this point. Compare both sides. They should be equal but I bet the right side will be shorter. A common problem on vettes it the lower control arm mount on the crossmember.Check for cracks or unusual bends by comparing it to the other mount.
The reason the car is pulling is due to lower caster angle on the right wheel. Hence all the shims on the rear of the upper arm.
My question is how did they come to the conclusion that the frame is not bent with the obvious stacking of shims. Bent control arms are very rare on a vette.
Also look very closely for cracks around the frame where the spring goes thru. Very common problem. Let me know what your measurements are and did the alignment shop give you the readings after they did the alignment.
Mike

 

[jbonifas]

Thanks Guys, I will be checking this out. I really didn't pay much attention to the numbers. I will get them and the measurements. Actually we measured from a bold on the frame to the upper ball joint and figured that the right wheel was 1/2" further back.

 

[jbonifas]

Still hanging on!!

OK, I have gotten the frame straightened. We have taken several measurements on front end and rear. l Everything is equal. The front end is now within spec. The rear end camber was off and reset, buit he toe is still neg. -.9deg.
Is this enough to keep it pulling to the right? I still have this right pull, tires are ok, maybe brake is dragging a little on the right, but the alignment guy said all he can do now is correct the toe in the rear. We would have but it looks like it has been some time since anyone loosened those bolts. Is there an easy way to shim the rear arms without tearing it all apart? Still looking for answers.

 

[Jack]

bent? where?

JCB:
Been watching with interest ... have alignment issues with my 71 also. Was your frame bent? If so, where? How was it straightened / what was done to "bend" to conformance?
JACK:gap

 

[c4c5specialist]

Measurements that you can use

Hi there,
There are 2 other measurements, that your alignment shop should be showing you to confirm a bent component.
Steering Axis Inclination, which is measured in degrees, when a caster sweep is done, will give you an exact difference between the left, and the right side.
You should NOT have a difference of more than .3.
Also, Setback will give you a more accurate degree, and location of the bent component, and what you can do to straighten out the suspension.
These 2 measurements you can use to correctly diagnose the condition, and correct it.
Have print out given and then we can proceed.
Let us know how you do, c4c5

 

[jbonifas]

Jack,
When we really inspected the frame, it appeared that the car took a hit on the right front. The front crossmember where the right lower control arm was connected had some old welding. The lower control arm looked like it it was angled in, if you tried to look straight down the bolt. When we measured the lower ball joint to a hole on the frame below the door,the right side was shorter (.5-1") than the left side. If you measured the front of the lower control arms on the cross member and compared it to the rear bolts on the lower control arm, it was 1" wider in front. Took it to a frame shop, the guy is pretty good, he said it wouldn't be a problem. I left it with him and when I picked it up, it was perfect. I didn't stay, but I am assuming he hooked up on the lower control arm and frame, heated it up and stretched it. He did put a little bead of weld on the lower control arm supports and along the frame. I hope this helps. I still didn't get the answer I was looking for, but I am closer than I was.
JCB