I'd start by checking the toe. It sounds to me like you have toe out. Does it "walk" all the time, or during braking?

The walk is mostly affected by the bumps in the road. It almost feels like play in the steering, but when its parked you can rock the wheel and get good response.

Yes.  The only way to set caster is to take two readings with the wheel turned 20 degrees out and 20 degrees in.  On the Fasttrax you turn 20 degrees out and zero the gauge, then turn 20 degrees in an you have a direct reading.  Doing it with an angle finder you have to subtract one reading from the other.  Again, not as accurate, and using turn plates without degree marks how do you know how many degrees you were turning?

The at home methods can be very accurate, BUT it all boils down to the tools you're using and how well you know how to use them.  I used other methods in the past, including angle gauges, but ultimately found them to have spotty, unrepeatable accuracy.  They were also time consuming.  With the turn plates and Fasttrax gauge I can do an aligment in a matter of a couple hours now. 

rpm wrote:

TKOPerformance wrote:

The only way to set caster is to take two readings with the wheel turned 20 degrees out and 20 degrees in.   

Not really. You can check & set caster from the upper and lower ball joint threads.


 

Not familiar with that method, could you explain
 

Last edited by Grabber Blu (11/13/2018 6:44 PM)

Since it appears from the pic you have cobra brakes using MustangSteve brackets, you can simply place a level along the bottom of the bracket, which is perfectly horizontal at zero degrees caster.  Any deviation from that is the actual caster amount.

Grabber Blu wrote:

rpm wrote:

TKOPerformance wrote:

The only way to set caster is to take two readings with the wheel turned 20 degrees out and 20 degrees in.   

Not really. You can check & set caster from the upper and lower ball joint threads.


 

Not familiar with that method, could you explain
 

For the right front wheel: With the wheels centered on turn plates you turn the wheel until the turn plate reads 20 degrees turning right, take a caster reading.  Now turn the wheel until it reads 20 degrees turning to the left.  The difference between the two readings is the caster.  Obviously its the opposite method for the left front wheel.  Then you just subtract the first measurement from the second, so for example, if the first measurement was 3.5 degrees negative and the second was 7 degrees positive; the caster angle would be 3.5 degrees positive. 

If you have a digital gauge you can zero its even easier.  Just turn the wheel out and zero the gauge.  Turn in an note the reading; that's the caster angle. 

The first method works if you have really simple tools, and I used it many years ago before I bought better tools.  It works, but is slower and the accuracy is somewhat suspect, not because of the method, but because of the tools typically used to measure the angle.  Better tools render it unnecessary, and I've never directly compared the two methods to verify the relative accuracy of the first method. 

The second method is how I do it with the Fasttrax gauge, which can be zeroed, and has a caster scale specifically for this purpose in addition to the camber scale. 

Certainly you can measure directly off the balljoints, or on other reference points on specific setups.  Truthfully this would never occur to me because I have to be able to align a half dozen different vehicles in my fleet of differing years, makes, and models.  Therefore the simplest way for me is to put the vehicle on the turn plates and affix the Fasttrax gauge.  There's nothing vehicle specific to remember other than how to make adjustments.  Basic KISS principle. 
 

rpm wrote:

I could measure that way if only I was as ingenious as the guy who designed the MustangSteve brackets. Those in the pic are the first disc brake brackets I made for my 69 disc spindles. The second set I made and currently using are on 70 drum spindles. Unfortunately neither set were designed with the proper angled surface.

They don't have to be at the proper angle.  ANY angle will work, as long as both sides are same.  Just determine what that angle is and convert accordingly.  Then you can calculate caster from a direct reading.  Camber is direct read from angle finder placed on back side of brake rotor.
 

John Ha wrote:

I've had similar problems.  I know that the local alignment shop does a good job on the classics but my suspension is like most others - it does not settle until after it's driven.

When they do the alignment for caster and camber, they jack up the front end to get the shims in.  When they let it back down it's not where it should be so they can't set the toe correctly.  I have an arrangement with my shop that they'll do the caster and camber, then I'll bring it back for the toe (and caster and camber check) after I've driven it and the suspension has settled back down to where it should be.

Yep, you can't do those adjustments with the car unloaded or they won't be accurate.  What I've done is a jack under each LCA going up at the same time, pull the wheel, make your adjustment, put the wheel back on.  Time consuming, but its yielded acceptable results.  That's how I have to do my WRX because the camber is adjusted at the strut to spindle bolts and there's no access with the wheel in place.  Otherwise it is adjust, drive the car around the block, check, and readjust if necessary.  And, yep, without caster being right there's no point is setting camber, and without caster & camber being right there's no point in setting toe.  Its all interrelated, so start with caster, then camber, then toe or you end up chasing your tail. 

John Ha wrote:

I've had similar problems.  I know that the local alignment shop does a good job on the classics but my suspension is like most others - it does not settle until after it's driven.

When they do the alignment for caster and camber, they jack up the front end to get the shims in.  When they let it back down it's not where it should be so they can't set the toe correctly.  I have an arrangement with my shop that they'll do the caster and camber, then I'll bring it back for the toe (and caster and camber check) after I've driven it and the suspension has settled back down to where it should be.

When I’ve do my alignments on my 66 I used 3 mil thick plastic garbage bags folded up under the tires. This allows the necessary slip the suspension needs to settle. I also bounce it a couple times. When I need to fool around with shims I loosen the upper arm bolts. With the weight on the suspension I turn the wheel both ways to get access to the control arm bolts and use a big screw driver or something to pull the shaft away and slip in the shims.

It’s really not hard to do your own alignment. I never did them before. One day I stopped and thought if I can do all this work, why not alignment? And why not? The Ford shop manual is a great source of info on doing it. My very first alignment the steering wheel was dead center and the car drove great. I didn’t have to go back and make any changes. The hardest part is just taking the time to paying attention to details.