How to set caster?

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67cuda360

67cuda360

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I'm just reading up a bit about DIY alignments and I'm wondering how to adjust the caster. From research I found it is best to get as much positive caster as possible usually somewhere around +2 - +4 degrees. But how do you set this..?

I found an image that Autoxcuda posted but i'm not sure I get what he means with "cam adjuster all in and cam adjuster all out"?

can someone enlighten me LOL
 

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Use the cams to pull the upper ball joint to the rear. then you will lose some, setting camber.
 
Not sure what you mean with "then you will lose some"..?

How does the cam move the upper control arm forward or backward? (to increasing or decreasing caster). Is it as simple as undoing the bolt (the one on the left side in the picture) on the one side and turning the stud on the other side of each upper control arm bracket to make it move.

I'm just struggling to understand how these cams work exactly.
 
When you rotate the cams, it moves the legs of upper control arm in and out.

When you only move front control arm leg "out" it actually pivots the whole control arm on the rear leg. That moves the ball joint to rearward.

When you only move rear control arm leg "in" it actually pivots the whole control arm on the front leg. That moves the ball joint to rearward.

If you max out the front cam adjuster all the way "out" and the rear all the way "in", you get the maximum caster setting for that wheel. Problem is, you need both sides caster to be pretty close (0.5 deg difference max). AND you have to set the camber setting. So... you end up going back and forth with caster then caster setting because they will effect each other. You'll do some juggling around...

First set the front adjuster max "out" and rear cam adjuster max "in"...Then check caster measurement both sides. Next, go to the side of the car with the most positive caster measurement reading and move that rear adjuster "out" so that wheel has the same caster as the other. Then, check and set camber by moving the front and rear adjuster "in" or "out" both the same amount. Then... Check caster and adjust if needed... Then camber and adjust as needed... back and forth.
 
67cuda360 said:
I'm just reading up a bit about DIY alignments and I'm wondering how to adjust the caster. From research I found it is best to get as much positive caster as possible usually somewhere around +2 - +4 degrees. But how do you set this..?

I found an image that Autoxcuda posted but i'm not sure I get what he means with "cam adjuster all in and cam adjuster all out"?

can someone enlighten me LOL
Click to expand...

The car is pointed to the right. The right picture is the front cam adjuster and A-arm leg.
 
Sorry, Ox, I was typing as you posted


OwdKasd said:
Caster is basically in or out at the top of the tire
Click to expand...

No, that's CAMBER. CASTER is tilting the tire forward or backwards so to speak, and the adjustment is made with the same cams

Here's how this works, if you were to loosen up the cams and move them, you can SEE this work

If you move BOTH CAMS TOGETHER, it moves the arm in or out as you are looking straight at the side of the tire. This tilts the top of the tire in or out perpendicular to the side of the tire, and this is CAMBER

If you move ONLY ONE at a time, let's say you move the FRONT one only. Depending on where the eccentric of the cam is now, when you move it, it will move the front of the are in or out AS YOU LOOK straight at the side of the car just as above. Because the rear cam has not moved, and the front one (let's say came out toward you) this "tilts" the arm TO THE REAR, and it will also change the CAMBER by some amount

The reason you hear people speak of "adjust the cams for maximum" or to recommend "offset bushings" is because with modern radial tires, you do NOT want to use the "factory book" settings that these cars originally did with bias ply tires.

IN FACT, so far as CAMBER is concerned, originally the tire would have been "tilted out" toward you at the top of the tire, where now with modern tires, you want it tilted IN at the top toward the car.

You either need to get a caster/ camber gauge, or you can actually make one, just Google around.

In this thread:

http://www.forabodiesonly.com/mopar/showthread.php?p=1780725

The "new" and the original specs are listed. NOTICE that the camber specs are NEGATIVE (top of tire "in") for radials, and the factory specs are POSITIVE numbers

Notice that original CASTER specs are NEGATIVE for some and the new specs are ALWAYS positive, and furthermore, goes WAY more positive than the factory ever did.
 
It's a pain. Put caster in, then pull some out, setting camber. A chebby, ford, same thing. Unless off set bushings, but haven't been there.
 
Ahhh.... I'm starting to get it :) I've been reading a bit about this and the issues that members seem to have after taking their cars in for alignments, like driving off with an even worse alignment situation (car being set to stock specs). Looks like I'll be doing some more digging and then tackle it myself LOL

I assume Caster (like camber and toe) needs to be set with the car on a level service and wheels pointed straight ahead correct? Makes it for a tight squeeze trying to adjust those cam bolts...
 
67cuda360 said:
Ahhh.... I'm starting to get it :) I've been reading a bit about this and the issues that members seem to have after taking their cars in for alignments, like driving off with an even worse alignment situation (car being set to stock specs). Looks like I'll be doing some more digging and then tackle it myself LOL

I assume Caster (like camber and toe) needs to be set with the car on a level service and wheels pointed straight ahead correct? Makes it for a tight squeeze trying to adjust those cam bolts...
Click to expand...
I would get the Camber & Toe sorted first. Then Check Caster. Caster most times is in spec or very close after setting Camber & Toe. I would still spend the extra $$ and get it on a good Alignment machine. JMO
 
I thought ride height was supposed to be set first, then caster, then camber and finally toe.. if I'm not mistaken.
 
Yes ride height first.I must of got lucky with my first try at setting the alinement on my 69 dart I got the height were I like it than pulled the front arms as far out as i could and pushed the rears as far as they would go,measured the toe.Car steers like on rails no pulling and the tires are wearing great,never did take it to a rack.Good luck you will get there.
 
Snake said:
Yes ride height first.I must of got lucky with my first try at setting the alinement on my 69 dart I got the height were I like it than pulled the front arms as far out as i could and pushed the rears as far as they would go,measured the toe.Car steers like on rails no pulling and the tires are wearing great,never did take it to a rack.Good luck you will get there.
Click to expand...

Did you measure the camber and caster degrees?
 
OwdKasd said:
I would get the Camber & Toe sorted first.
Click to expand...

The only thing I do with toe (if the entire front end has been apart) is simply rough it in so the wheels are halfway straight and the wheel is "near" centered.

1 Ride height, jump the car up/ down to "settle" suspension and take your time until satisfied

2 Set caster/ camber together

3 Set toe last.

You can MAKE the tools you need to align a front end, Google around, or you can buy a caster / camber ga. several places.

I got lucky. Some time ago, I found an old Ammco caster/ camber ga, some swivel plates, and a toe jig used for not much money

Read this thread:

http://www.forabodiesonly.com/mopar/showthread.php?t=183214
 
That's what I love about this site, when I have a question, you guys usually already answered it.

I just bought the rebuild kit off ebay and replacing ball joints and bushings. At the risk of highjacking the thread, How do you get the bushings out of the A arm?
 
..just as Snake said,although i had to bring the rear of the upper "A" arms out a bit to get a camber a degree or so within vertical.
..my toe in is a hair less than 1/8" and all seems fine so far...2000 miles and counting!
..i set the toe in with 30 "straight edges on my discs and the discs resting on 6 x 6 blocks of wood.
 
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