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71 Road Runner: having trouble getting the alignment numbers I wanted!

Kern Dog

Life is full of turns. Build your car to handle.
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I've had good luck getting my Charger to steer and handle the way that I like, so I took what I'd learned and tried to help out a friend with his 71 Road Runner.
He is the original owner and has made small changes over the years, but nothing too drastic. He wanted a firmer ride and more responsive steering so we added the following:

1.0 torsion bars replaced the stock .90 bars.
MP XHD Hemi leaf springs replaced the stock 5 leaf pack.
Welded in 3x3 frame connectors.
upper Control Arms with offset bushings installed to increase caster.
Fast ratio Idler and Pitman arms.

The car sits at what may be considered stock height. I didn't measure it but it looks about where I've seen others sit. 15x7 wheels, 235-60-15 tires. He had the car aligned today. I went along to tell the man that he didn't want the stock 1971 alignment specs, I had the following:
0 to 1/2 degree NEG camber
2-4 degrees POS caster
1/8" toe in.

The alignment guy couldn't even get close to anything except the toe #. Why? the car has never been wrecked. The parts are all stock except the bushings in the upper control arms. The car came with 14" rally wheels but that shouldn't make much difference. I didn't get a copy of the sheet but the numbers I recall were almost zero caster on the left, something like 0.2 and about 0.8 on the right with slight positive camber on both sides. What the heck??? wouldn't adding some NEG camber automatically get you more caster? There is more adjustment left in the alignment cams, I could see that.
The owner said the car feels twitchy. I know that Fast Ratio arms with overboosted steering will make a car feel a bit funny but the car felt okay to me. The steering wheel returns to center after a turn. My Charger has the same basic setup as this Road Runner but mine feels rock solid. I had mine aligned at a different place and was able to get 4+ degrees of caster on both sides along with .75 NEG camber.
The obvious suggestion might be to take the car to a different shop. My first suggestion months ago was to go to the guy that I use. I'm just curious to learn if I did something wrong or if I missed something.
The bushings in the Upper control arms were pressed in so that the front side bushings had the thin spot toward the engine. The rear bushings have the thin spots toward the fenders. It seems that this should have easily resulted in getting the numbers we asked for. It was aligned 9 months ago at the same shop after he replaced tie rod ends. At that time it still had the stock UCA bushings. The numbers were not much better than what we got today.
The owner is not interested in buying tubular A-Arms. If he was dying of thirst he wouldn't spend $10 on a bottle of water.
I'd appreciate any suggestions on what else to try. I'd like to not only help this guy, but others in the future. Thanks, Greg
 
The bushings in the Upper control arms were pressed in so that the front side bushings had the thin spot toward the engine. The rear bushings have the thin spots toward the fenders.

That explains the problem - they are installed wrong way around.

To increase the caster, offset bushings are meant to allow the upper ball joint to be adjusted further back. The way you have them will move it further forward.

EDIT - Ignore what I wrote above as I was confused. The bushing ARE in correctly.
 
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That explains the problem - they are installed wrong way around.

To increase the caster, offset bushings are meant to allow the upper ball joint to be adjusted further back. The way you have them will move it further forward.

I'm having trouble seeing how my method is wrong. With the rear bushing: If the mounting hole is offset towards the outside of the car, it allows the end of the arm to move closer to the engine.
 
This is a Right side (Passenger) UCA that I was ready to use until the owner saw a defect near the ball joint sleeve. The bushings in this arm are in the same position as they are in the others that I did use.
 

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Apologies Greg, looking at the last photo I realize they are installed correctly (I got confused :black_eye:)

In which case, I have no idea why your aligner could not achieve sufficient caster :icon_cry:

- - - Updated - - -

There is more adjustment left in the alignment cams, I could see that.

I would take the car to where you got yours aligned Greg. If something is still not right, get them to explain how/why. If all goes well there, go back to first shop and ask for money back. :argue:
 
Yeah, I am thinking that a more seasoned (Old guy) mechanic like I have used before would have been a better choice.
 
Greg,
I had a very good experience at Clark Frame & Wheel Alignment in Roseville. Good guys and they know our cars:
clarkframe.com
209 Kenroy Ln. #10 (off Riverside)
Roseville, CA 95678
916-783-4292
Tony or Case
 
Thanks, friends.
Today I was over at the owners house. He had read online about the Power Steering shim/washer trick and wanted my oversight. I reminded him that I had told him about this mod several months ago but he acted as if yesterday was the first time he had ever heard of it.
For those wondering, In the case of the Saginaw Power Steering pumps, it is possible to reduce the pressure in the pump. This is done to reduce the "Tires on ice" feel of the overboosted power steering pump. Reducing the pressure from the approx 1400 psi down to 700-850 has the effect of increasing the resistance to turn the wheel.
The valve had one .015 washer/shim in it, we added more to arrive at a .125 thickness. It served to be too much, as the steering became almost impossible with the car at rest. He will have to dig in again to take a few washers out.
For those interested in the Mopar Action article on this, google "Pump it Down".
 
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