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could be my imagination but it looks to me that your archive photo (stripped or silverish color shock tower) looks deformed around the bolt holes. The rear bolt hole appears proud slightly and the front is depressed a little. I think this car may have seen some action in its past, perhaps some "air time" ;o), I would forget about thinking no shims = 0 castor and shim the front to get to zero. AFter 50 years, believing anything is square on these cars (even out of the factory) is a fool's errand...

I also have a hard time believing the tool and 2x. IF the tool gives you camber readings directly, as in wheels pointed straight and install the gauge - read the measurement, then Castor is just the difference between Camber reading 20 degrees in and camber readings 20 degrees out.
 

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Discussion Starter #23
I'd say to check your strut rod bushings. It really appears to me that the LCA is too far back judging from the photos that I took of mine when I was rebuilding my suspension.
I suppose I could go tighter on the strut rods, but seems like it would just put the LCA into a bind on the mount point to the chassis.

Have you checked that your upper Control arm shafts are centered left to right and the same on both sides? Most new arms are not assembled with consistent centering of the shafts. You want to ensure they are centered or slightly off center for more caster. Opentracker racing has some details on his website. From your pics, it looks as though you have some quality parts, so perhaps you already have blueprinted upper control arms.

Looking back at my notes, I did center the UCA when I got the new ones. One was off 1/16" and I fixed it. One was OK,

James
Do you know your UCA shafts are centred? Did you deliberately offset them?
Ending up with a left and right arm, then put them on the wrong side?
I did not offset the arms, just went for centered.

Was it this way before you did the work? If not, I guess I’m in the UCA off center camp. Are the strut rods correct for your car?
From the pics I have before teardown it does look like the UCA is sitting forward as I have now.

could be my imagination but it looks to me that your archive photo (stripped or silverish color shock tower) looks deformed around the bolt holes. The rear bolt hole appears proud slightly and the front is depressed a little. I think this car may have seen some action in its past, perhaps some "air time" ;o), I would forget about thinking no shims = 0 castor and shim the front to get to zero. AFter 50 years, believing anything is square on these cars (even out of the factory) is a fool's errand...

I also have a hard time believing the tool and 2x. IF the tool gives you camber readings directly, as in wheels pointed straight and install the gauge - read the measurement, then Castor is just the difference between Camber reading 20 degrees in and camber readings 20 degrees out.
I can't say for sure on the bolt holes. One on the driver side was cracked and a little bit proud but I fixed it. Nothing on the front end frame ever looked like any accident had happened, but the valance and stone guard were not original. Could have been a fender bender or maybe something else that has things out of whack. But since it seems equal on both sides, I am thinking that is not the case.

As for no shims, I only have it that way now as a data point. It looks like +/- 3/8" shim stack is where I will be at for -.5 to -1.0 camber. With no shims I am at -3 degrees camber or so.

The 2X multiplier is in the instructions for my alignment kit. I have seen 1.5 multiplier in a lot of other searches so I I really don't know what is correct.

I am to the point where I think I will just align it to the best camber and toe I can and maybe offset caster a little (up to 1/16" difference in shims front bolt per Ford manual. I just can't see any mechanical problems.
 

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a) Your caster angle is going to change with the weight on the suspension.
b) You may be confusing caster angle with "steering axis inclination", which is an imaginary line through the centers of the upper and lower ball joint studs... true caster angle is where that imaginary line is being projected in relation to the tire contact patch. If you look at the angle that the UCA is mounted (horizontal position of the shaft), as the suspension is compressed the upper ball joint is going to move SIGNIFICANTLY rearward.
 

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Tell me your current amount of caster, camber, and shim stack thicknesses at both the front and rear bolts. State whether + or - too.
 

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I suppose I could go tighter on the strut rods, but seems like it would just put the LCA into a bind on the mount point to the chassis.
If you see this as an option, well, there's your problem. This is not an optional adjustment on your car(unless I missed something). Get it right and forget it.
Set caster first. Bounce it and roll it back and forth some after every adjustment and measurement.
 

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Discussion Starter #28
Tell me your current amount of caster, camber, and shim stack thicknesses at both the front and rear bolts. State whether + or - too.
I have set 3/8" shims on all 4 corners as a starting point. Of course need to tweak some but this is where I am at

Toe - 1/4" total (Note I got this close before I started any camber/caster measurement)

Camber - zero gauge to garage floor and measure directly
Left: -0.85°
Right: -1.05°


Caster (Note I just measured and my tool sets to 15° not 20°)

Left:
with wheel turned inward 15° I get camber of 90.00° after zeroing to my garage floor. Then I zeroed the digital level and rotated outward 15°. I get -1.35° with the top of the wheel inward (bottom of wheel out further). As a double check, I also then zeroed the gauge to the garage floor and got -1.5°. Instructions say multiply by two so that would be -2.7° caster

Right: with wheel turned inward 15° I get camber of 89.75° after zeroing to my garage floor. Then I zeroed the digital level and rotated outward 15°. I get -2.1° with the top of the wheel inward (bottom of wheel out further). As a double check, I also then zeroed the gauge to the garage floor and got -2.15°. Instructions say multiply by two so that would be -4.2° caster
 

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Discussion Starter #30
If you see this as an option, well, there's your problem. This is not an optional adjustment on your car(unless I missed something). Get it right and forget it.
Set caster first. Bounce it and roll it back and forth some after every adjustment and measurement.
3/8” on all for corners??? To gain positive caster the front of the UCA has to be spaced out rather than the rear. Have no shims on the rear studs of my UCA’s.
Yes for starting point. The manual says 1/32" shim = ~ 0.5° caster so max I can get is 1° of adjustment as you are limited to 1/16" mismatch front to back. So if I shimmed 1/16" more on front I still have negative caster.
 

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I would highly recommend the LCA camber Kit from ORP. Set it and forget it. Then you only have to adjust caster with shims on the UCA’s. One step farther, get SorT adjustable strut rods for fine tuning the caster.
 

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I'd do the following:

LH side
Front bolt: add 1/8" - 5/32"
Rear bolt: remove 3/16"

RH side
Front bolt: add 7/32"
Rear bolt: remove 7/32"

I created a spreadsheet awhile back to minimize trial and error. The above should keep your camber at -1 and get you roughly +2.5 caster.
 

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....as you are limited to 1/16" mismatch front to back.
Forget about that if you are trying to align the car with positive caster for modern tires. You will end with nearly no shims a the rear bolt and max possible shims at the front bolt. That's not a problem, my car have been driven like that for years. The suspension wasn't originally designed for positve caster, because that wasn't used with vintage tires.

I'm not sure you pics show anything usable, because the car are not standing on the ground with the suspension settled in ride hight. The upper UCA are angled so the caster will change with suspension position.
 

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Discussion Starter #35
Personality, I wouldn’t worry about the 1/16” mismatch side to side. Remember your car is now 54 years old. Do you really think it’s within 1/16” side to side?
Got it. Seems like that is the consensus. Thanks for all your help

I'd do the following:

LH side
Front bolt: add 1/8" - 5/32"
Rear bolt: remove 3/16"

RH side
Front bolt: add 7/32"
Rear bolt: remove 7/32"

I created a spreadsheet awhile back to minimize trial and error. The above should keep your camber at -1 and get you roughly +2.5 caster.
First off, thanks for the help!

So take these numbers with a grain of salt. I really think I need to get out and drive it a little to settle everything after all the changes (and I have had the wheels off the ground). I have been rolling the car 8 ft or so back and forth but still need to get it truly settled and check again. Too much rain now and I do not have a convertible top and my hood is off.

But I got the point now about abandoning the 1/16" difference limit

LF - 1/2" shims
LR - 3/16" shims
Difference front to back - 5/16"

RF - 19/32 shims
RR - 5/32 shims
Difference front to back - 7/16"

Toe - 1/8" total (Note I re-adjusted this after re-shimming and before I started any camber/caster measurement)

Camber - Same process as before
Left: -0.55°
Right: -0.70°

Caster - Same process as before
Left: +0.3° caster
Right: +1.4° caster

So it moved a lot but again, maybe the suspension is not properly settled from before this or after this trial. I will report back when I can get it out for a quick spin and re-measure.

If these numbers are accurate then I will adjust and shoot for -.75 camber and +1.5 caster (leave right as-is) and adjust left by adding 1/32 to the front and removing 1/16" from the rear.
 

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Caster = 180/3.1416*(C1-C2)/(T1-T2).
C1-C2 is the camber difference at wheel turn from T1 to T2.
For 20 degrees wheel turn each way (40 total), you would have to multiply your measured camber difference by ~1.432 to get caster.
For 15 degrees (30 total), you’d multiply by ~1.91
When you see the 1.5 and 2 multipliers they are just rounding the above numbers.
 

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Discussion Starter #38
Caster = 180/3.1416*(C1-C2)/(T1-T2).
C1-C2 is the camber difference at wheel turn from T1 to T2.
For 20 degrees wheel turn each way (40 total), you would have to multiply your measured camber difference by ~1.432 to get caster.
For 15 degrees (30 total), you’d multiply by ~1.91
When you see the 1.5 and 2 multipliers they are just rounding the above numbers.
Thanks for this! Makes more sense now that I can see the equation. Quite simple actually. And now we know where the "2" and "1.5" factors come from....

Good Lord...I like math, but I’m glad I bought a Longacre bubble gauge.
Bubbles are so 1990s!!!! (but simple and don't need batteries!!) I bet there is an app for our phones to do caster.....
 

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Discussion Starter #39 (Edited)
Finally got back to the alignment now that the rain quit for couple days. Final specs for now (might tweak it after really driving it some miles):
This is for a 66 vert with stock suspension (but all new) and 215/60/15 BF Goodrich Radial T/A tires. Alignment specs were based on recommendations from VMF and not the Ford manual.

LF - 17/32" shims
LR - 3/32" shims
Difference front to back - 7/16" (or 14/32")

RF - 9/16 shims (or 18/32")
RR - 3/32 shims
Difference front to back - 15/32"

Toe - 1/16" total toe in

Camber
Left: -0.72°
Right: -0.82°

Caster
Left: +1.9° caster
Right: +1.8° caster

Drove it after and it tracks dead straight, but I have no return to center at all, but my Prius EPAS is likely the cause of that. I need to look at some old threads I saw in the past about that.

Thanks VMF for all the help. Glad I was able to do the alignment and I am confident it is better than what I could get at a local shop.
 
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