I think I'm seeing that the HOLE is out towards the fender, which makes the ARM move inward towards the frame.
DIY Front Alignment Troubles
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flingdingo
Well-Known Member
Yeah, you've got 'm backwards. The way you have the bushings in now, the ball joint will be pushed to the front of the the car. You want the ball joint pushed to the rear for maximum caster.
72blunblu's diagram is a bit misleading, since your bushings don't appear to have arrows on them, but read the text under the picture. Or better yet, grab a pizza box; draw yourself a line near one edge, this line is your control arm bolts. Set your control arm on the box with the bushing holes centered on your line and plot where your ball joint is. Then imagine the bushings centered, plot your balljoint position again, and then imagine the bushings opposite of your current installation, plot again.
My explanation isn't great (no coffee yet) but my point is a full-size picture might help you understand what is happening, and what you are trying to make happen.
72blunblu's diagram is a bit misleading, since your bushings don't appear to have arrows on them, but read the text under the picture. Or better yet, grab a pizza box; draw yourself a line near one edge, this line is your control arm bolts. Set your control arm on the box with the bushing holes centered on your line and plot where your ball joint is. Then imagine the bushings centered, plot your balljoint position again, and then imagine the bushings opposite of your current installation, plot again.
My explanation isn't great (no coffee yet) but my point is a full-size picture might help you understand what is happening, and what you are trying to make happen.
Ok. I think I have a grip on this. When I install the bushings correctly, I will effectively be lengthening the front of the Control arm and shortening the rear arm.
mopowers
Well-Known Member
Yes. Great way to put it!
Think of it this way. You want to make the controls arms LONGER on the front sides and SHORTER on the rear sides. Look at the position of the bushings with that in mind. The way they are now installed, you are achieving the opposite of that. The goal is to tilt the steering axis BACK toward the rear of the car at the upper ball joint. That increases caster. Long in the front. Short in the rear. That means bushing hole towards the CENTER of the car n the front. Bushing hole towards the OUTSIDE of the car at the rear.
Does that make sense?
Does that make sense?
By George! I think I've got it! Thanks everyone for your help. I'll get the bushings installed correctly and then make myself a pair of turn plates and be done with this alignment stuff.
OK gang. I removed the bushings and installed them correctly. The front adjuster was turned to move the front of the control arm out and the read adjuster was rotated to move the rear of the arm inward.I lowered the car and did a quick camber measurement. I was disappointed to see that both sides are showing 2* positive camber. I thought for sure that I would see negative camber after everything was installed correctly. Are my expectations unrealistic?
I will be working on the alignment some more this weekend. I will adjust the front suspension height as per the service manual and check my numbers again.
I will be working on the alignment some more this weekend. I will adjust the front suspension height as per the service manual and check my numbers again.
With the offset bushings installed correctly you shouldn't have a problem getting negative camber and positive caster. Getting something in the range of -.5° camber and +3.5° caster shouldn't be too difficult.
That said, you MUST set the ride height first. If the ride height is way off, the alignment numbers will be way off too.
Thanks 72 blunblu. I'll set the ride height and go from there this weekend.
OK gang here is the latest on my DIY front end alignment. My day started off by fabricating turn plates to determine my caster after camber was dialed in. I made the plates from 1/4" steel on the bottom and 1/8" steel on the top. Did a little welding for the pivot point and my handles. The top plate was coated with Herculiner and the underside of the bottom plate was covered with carpet antiskid padding. I lubed the plates with graphite spray. I have to say that the worked very well.
Now here is the rest of the alignment story. I set the ride height as per the factory manual at 2 1/8". Left and right camber was adjusted to -0.6* as per the Skosh chart. Measured caster on the left was 0* and the right was -1.2* Obviously nowhere near +2.5* camber that I'm looking for. What do I do next?
Now here is the rest of the alignment story. I set the ride height as per the factory manual at 2 1/8". Left and right camber was adjusted to -0.6* as per the Skosh chart. Measured caster on the left was 0* and the right was -1.2* Obviously nowhere near +2.5* camber that I'm looking for. What do I do next?
autoxcuda
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I start off roughing in the toe and getting the steering fairly straight. Not super accurate, but close. Don’t start off with the thing completely pigeon toed with the steering wheel headed to right field.
Next adjust the front cam all the way outward.
Then adjust the rear cam all the way inward.
That maximizes caster.
Now check camber with gauge and bring in the front cam inward until you get to 1/2 deg negative camber (top of tire inward slightly from bottom). Do both sides.
Check and Rough-in again toe
Then check caster both sides.
The side with the higher positive caster... adjust the front cam inward some and the rear cam outward some to get back to 1/2 degree negative camber.
You want the front and rear leg to move the same amount so the camber stays the same. But that won’t always be turning the wrench on the cams the same amount because of the cams action.
Check caster on that side again.
Keep adjusting the cams in that side and then check caster until the caster matches the other side of car and camber is 1/2 deg negative.
Now set toe and get steering wheel dead straight.
Did you bounce the front end good after you let it back down on the ground?
How can we tell you what to do next? You've left out a very important point. How are the cams turned? Pictures would help a lot.
Doesn’t matter, bouncing the front end doesn’t work to set the alignment. The tires have to roll otherwise the change in height won’t happen.
When the tires make contact with the ground as the car is lowered the alignment is different than at ride height (the front suspension travels in an arc). The tires tip out at the tops at full extension, narrowing the track. The friction of the rubber on the ground holds the tire patch in place as the car is lowered. Bouncing on the front end of the car won’t slide the tires across the ground, so it won’t settle the suspension all the way unless you roll it. Unless maybe you’re running bicycle tires on a polished concrete floor.
To do it right you have to drive up onto the turn plates in the front, not jack the car up and slide them under.
It certainly does work with turnplates that have bearings in them. If what you say is true, that means every alignment man in the world has to roll the car off the rack and back on to get the ride height back right after jacking it up. How stupid does that sound?
I started with the front adjuster all the way out and the rear all the way in. Since I had postive camber, I only adjusted the front to get -0.5* camber. At that setting I'm getting 0* caster on the left and -1.2 on the right. I did not roll the car onto the plates. I understand why I need to do that rather than lowering the car onto the plates.
I will follow autoxcuda's advice and start to adjust front and rear adjusters on the right side to try and maintain -0.5 camber and obtain positive caster. Looks like I be doing a lot of jacking and rolling to get things maximized.
I will follow autoxcuda's advice and start to adjust front and rear adjusters on the right side to try and maintain -0.5 camber and obtain positive caster. Looks like I be doing a lot of jacking and rolling to get things maximized.
Can you post pictures of the upper control arm installed on the car on one side please?
I'll post a picture later today Rusty....after we get back from church.
pishta
I know I'm right....
could you not do this by jacking the wheels up from under the lower ball joints? That way you could get the tires up and allow them to turn or pivot freely while maintaining ride height?
autoxcuda
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I don’t like that right side number. So you started with front cam all out and rear cam all in, then just moved front cam in to get -.5 camber.... and that got you -1.2 caster.
There no adjustment left on that side for more caster. It’s maxed out.
You’ll have to go to the left side and reduce caster to get it to match the low side (right @ -1.2 caster).
So is there a pin in the turnplates you made so the plate turn on than axis point?
Like side before, they have to be free of movement in all directions.
You can put 2 pieces of thin sheet metal with grease between then allow the suspension to move out and in when you lower the car and bounce it to get it to settle.
don't forget your A body has anti-dive top arms so they are very sensitive to ride height.
full droop
not quite full bump
looking at your vehicle photos on another thread the ride height is fairly high (factory standard?) so it'll be very difficult to get a decent amount of caster. Rear ride height will also affect front caster as your measurement is the angle of the ball joints from 90 degrees vertical or a right angle to gravity. Camber will also change with ride height due to the unequal lengths of the top and bottom arms.
full droop
not quite full bump
looking at your vehicle photos on another thread the ride height is fairly high (factory standard?) so it'll be very difficult to get a decent amount of caster. Rear ride height will also affect front caster as your measurement is the angle of the ball joints from 90 degrees vertical or a right angle to gravity. Camber will also change with ride height due to the unequal lengths of the top and bottom arms.
Ok, you say patato I say potahto. They turn AND slip. I don't really give two craps what they're called. They DO what I said they DO and THAT'S THAT.
Those "turn plates" in that video both TURN AND SLIP so there's NO NEED to back the car off to get camber correct after jacking the car up. That was the whole point I was making.
another measurement that can be done is the king pin inclination. this has to be done on turn/slip plates with the brakes locked.
what this will tell you is if the upright is bent. if the KPI is the same each side but the camber is different then something is bent. if they are out by the same amount then it's down to adjustment.
the KPI is the angle of the ball joints, the camber is the angle of the wheel/upright.
what this will tell you is if the upright is bent. if the KPI is the same each side but the camber is different then something is bent. if they are out by the same amount then it's down to adjustment.
the KPI is the angle of the ball joints, the camber is the angle of the wheel/upright.
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