Does anyone have some good photos and description using the string method to get the rear wheels tracking with the fronts and getting the toe set? Body is off my '64 and I have new trailing arms. I've read several threads on the subject but haven't seen any good photos.

Thanks,
Patrick

 

No photos, but these might help.

https://web.archive.org/web/20150912...r%20Camber.pdf

https://web.archive.org/web/20160329...-alignment.php

 

There are lots of good U tube examples

Here is an example


Phil

 

God knows I'm far from an expert - but I believe you need the body on and "weight on wheels" to align things....you can't really even torque the front trailing arm bolt without these conditions - which affects the shim packs I would think...

Others can tell me if I'm "full of it"...

 

Well, you are full of it, but that is another story...LOL Yes, the car should be fully weighted to do an alignment

 

Thanks for the info guys, you're awesome. Yep, vehicle needs to be assembled, I remember that now and probably would have figured it out when I got to looking at the camber and going "wow, I've got a whole lot of positive camber to get out!"

Patrick

 

Depending on the completeness of your suspension, you can more easily and accurately align it. If the springs are out of the vehicle, but the rest of the suspension is complete, you can set your ride height and achieve a perfect alignment without the body or even drivetrain in place. I have four wheel coilovers so it was even easier, but that is how I would proceed.

 

Here's a photo of a C4 on our Original Hub Stands. The same concept applies when measuring to the wheels you just need to compensate for measuring over a smaller distance. Converting to degree is the easiest way.



We have a laser system now with the Mk II hub stands but I do not want to steal the thread, if you're interested we'd be happy to talk to you about it!

Hope these pics help!

Colton

 

You are correct. Without adequate weight on the suspension, you can't do this job very well. Wait until then. The factory had special machines made for this job..........ones you don't have at home.

I used a level and carpenters square to do mine at home when rebuilding the suspension, and got pretty close. Then do the "string method" ,or go to a professional shop for final alignment. I chose the latter at this time.

I purchased the FASTRAK alignment tool awhile back for doing alignments at home, but wanted a good alignment on a Hunter pro machine to be used as a reference. Now should be able to handle things from here out by myself..

Larry

 

Factoid is correct. Doesn’t matter if body is off or on, first step is set/check ride height. If wrong, correct that first. No body, frame can be anchored down or weighted. Body on, may need to be raised a bit even. Springs do sag.

I’ll pass on whether or not Frankie is full of it, but he can be helpful

 

Oh, Frankie is definitely helpful, but aren’t we all full of it at times?!

 

I like the idea of aligning with the body off, seems like it would be easier than with body on, especially since I don't have a lift. Wouldn't be hard to pull the springs off, but what is the right ride height to set the frame to?

 

It should be in the shop manual. It was in later years.

 

See dimensions D and Z with the adjustments for options in the tables as required. If you are off by 1/4”, it will have minimal impact on your alignment.

 

Many years ago, as a college student, I worked at the GM testing ground. They aligned the test cars with the driver seated inside, or with an equivalent load of sandbags in place to simulate the driver. Can't remember what they did about fuel level.

 

Install the suspension components without the springs. On the front just tighten the lower ball joints nuts and tie rod to knuckle nuts to "snug", so they will come apart easily to install the springs.

Block up all four corners to the Z and D dimensions in the shop manual/AMA specs to the curb weight spec, which is normal ride height with full fuel, but not occupants or cargo. Install the wheels/ tires and use an inclinometer to measure camber and the difference in front camber with the wheels at full right and left lock is caster, but be careful to get the correct sign.

To set toe, measure the center point of all cross members as close as possible, then draw a string down the centerline and use plumbobs to align the string vertically to the same height as axle centerline and measure toe for each wheel from the string to a reference points on the tire, which must be the same on both tires of each axle.

The above will get you in the ballpark, but once the car is completed, you should take it to an alignment shop, check all the settings, and change as necessary to dial them in as close as possible to whatever specs you chose.

Duke

 

All the rest made sense, but the bolded part I'm confused on. I think what your saying is to find the cross car center point along the cross members and this will give the centerline of the frame. Then place a string outside of the tires that is parallel to the centerline of the frame. Place another string on the other side of the car the same distance from centerline. Is that correct?

Patrick

 

Hi Patrick,

The car must be level front to rear and side-to-side.

You will need some type of slip surface under the front wheels that will allow you to turn the wheels without changing the level of the car.

I have taped the tires and marked a center line on each to index the alignment,

A good caster camber gauge is a must.


Good luck

 

Personally, putting the wheels on defeats the purpose of aligning without the body and drive train. I would use four pieces of angle aluminum cut the length of the diameter of the tires (27”) and bolted to the wheel drums (or discs if you have updated to discs). You can then orient them horizontally for toe and vertically for camber and front caster. This eliminates tire friction on the floor and the resultant errors and changes in ride height it can introduce as you make adjustments.

 

You only need one string. Your measured cross member center marks should line up straight. Tie the string to the front and rear cross member at their centers and verify that it's inline with all the cross member center reference marks. Use a couple of plumbobs and adjust the string length to get the string to the same vertical height off the ground at rear axle centerline a little beyond the front and rear tread faces. Place a reference mark on the forward face of the tire tread. Measure from the string to the tire reference point. Now rotate the tire 180 degrees so the tire tread reference mark faces to the rear and measure from the string to the tire reference point, The difference between these two measurement is toe.

For radial tires set as close to 1/32" toe-in per wheel as you can achieve. That would be when the string to tire reference point dimension is 1/32" less with the tire reference point facing forward than when the tread face reference mark is facing to the rear.

As I said, this will get you in the ballpark. A final check on a four wheel alignment rack when the car is complete should be done, and dialing it in should only require swapping shims from side to side, and for this reason its a good idea to have a couple of 1/32" and at least one 1/16" shim both inboard and outboard on each side.

Also remember that the shims should be a slight interference fit. Fill the spaces with shims until a 1/32" shim won't slide in by hand. Then remove a thick shim, install the 1/32" shim and then reinstall the thick shim, which should require light tapping with a hammer to seat.

You can do the same for front toe, but be sure the steering gear is centered, which can be tough without the body and complete steering system installed. You will be in the ballpark if the left and right tie-rods are equal length with toe set at 1/32" per side.

Duke