1973 Plymouth Duster repair and rebuild

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Ok, its not road worthy yet. But I had to see how it looks on the ground. The rear leaf springs are worn out. So I may need to consider lowering the rear once the new leaf's are installed. The other option I am considering is lifting the front end 1 inch. I need to get the car on flat ground and see where it lands to better judge what my next move will be. I have about 1.5 inch of spacing I can add to the rear tires. I will get pictures of it, and look for opinions later.

I need to fasten the shocks to the axle, shorten the drive shaft, install the steering column, and bleed brakes. I will be re adjusting the front suspension 1 more time before taking it to the shop for a alignment.

I am so happy. You would have to surgically remove this grin from my face.

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So here is a good picture showing the wheel fitment in the front and rear wheel wells. With where the front wheels landed, I am considering spacers for the rear.
Yes, I know about the headlight. :-)

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Of course at this point I had already welded the perches to the axle. Drilling thru the leaf spring with a sacrificial uni bit was cake with the leaf pack torn apart. Had to get a second bit to drill thru the last leaf. Slow speed and consistent force for the win. Other than I need to buy leaf spring clamp set, its done. And the clamps are not really necessary right away.

Its kind of funny you would say you would have purchased the correct perches.... I bought mopar performance perches. There is a assumption there that failed me. But it does make sense, larger axles are normally for bigger power. Small leaf springs are not used in big power setups. And a center pin with 5/16 threads would snap under the load of big power. What I need are new leaf springs. For the time being, this is what I have until I can gain employment. I will be replacing the leaf's and shocks in the future.

There is another element to this, if you haven't had to change perches and leaf spring pins, it sucks. The hole diam in the perch is not normally provided in the specs. Its as if there is a assumption and I dont have the experience to know it. And when you try to buy a 1/2 center pin, you find out that the 1/2in thread diam is listed and not the pin diam. And of course there are several different thread and pin diam combinations. Non of which are listed, cause that would make sense I guess.

A final thought, I bought a perch kit for a Ford 8.8 first. Only to find out that I had to buy a chevy Dana 44 perch kit for my ford axle as my 8.8 came out of a ranger and had the smaller axle tube of 3.25. Explorer axles are 3.5 inch which was what was delivered as thats what I purchased. Hence my first purchase was wrong. And the company would not exchange it due to buyers fault even though their website show NO sizes on the description. Maybe a note on the 8.8 description that the kit was for large tube 8.8 out of suv's and large trucks. I finally found the mopar performance perches for the 3.25 inch tube diam as well as a u-bolt kit for the correct diam. And I elongated the new base plate holes 1/8 in inward to fit the u-bolts as finding new base plates for 3.25 was impossible. Let alone finding them with the shock mounts integrated the same as factory a-body.


Both good points. Regarding building a bushing, I dont know if I stated earlier (few weeks ago) here but my metal lathe broke trying to build a crush sleeve for the front end. Not that matters due to the required dimensions. The pin head is 1/2in (.500), the perch hole diam is 5/8in (.625), leaving a difference of 1/8in (.125). That means my sleeve wall thickness would be 1/16in (.0675). So then I could use loctite to glue it to the pin. But slip fitting it (cut slightly smaller ID, heat it up and tap it down) would not be a good idea as the sleeve would most likely fracture. I would be more likely to use a larger grade 5 bolt, turn the head down to 5/8 and partial round, and turn the shank and threads down to nominal for 5/16, then single point thread. I would be concern a grade 8 would be to tough and become brittle during the lathe work.

As far as welding up holes and re-drilling, I wouldn't want to introduce inaccuracy into the setup.
I said that because it's a real well known piece of information. I THINK what they did there was make the centering holes larger to facilitate the bigger centering pins the super stock guys were using at the time. If it's not that, I don't know WHY the heck they did it. lol
 
I said that because it's a real well known piece of information. I THINK what they did there was make the centering holes larger to facilitate the bigger centering pins the super stock guys were using at the time. If it's not that, I don't know WHY the heck they did it. lol

It sure would be helpful if manufactures and suppliers would provide relevant information such as pin size in addition to thread size. And what pin size is accepted in the perch. I know thats nothing this thread will fix, just the expression of 1 persons opinion.

Well, in any case, I have a working solution.
 
It sure would be helpful if manufactures and suppliers would provide relevant information such as pin size in addition to thread size. And what pin size is accepted in the perch. I know thats nothing this thread will fix, just the expression of 1 persons opinion.

Well, in any case, I have a working solution.
I'd just get a bushing. So simple to make.
 
So, Merry Christmas to all. Hopefully everyone has a relaxing holiday thru the rest of the year.

I am looking for good ride height measurements to get my car based too. Copilot is saying....
  • Front: 14in fender lip to spindle center
  • Rear: 15in fender lip to axle center

Do those numbers look good?

And for starting alignment numbers:
  • Camber: -0.5 to -1.0
  • Caster: +2.5 to +3.5
  • Toe-in: 1/16
I do plan on the car going to alignment shop. I am just trying to get it close to minimize shop hours. Currently we are thinking 4 hrs with all the adjustments planned.

Provided procedure

Camber ~ Use your digital angle gauge on the rotor to measure vertical angle​

Target: –0.75° (perfect balance for street driving)​

How:​

  • Wheels straight
  • Gauge on rotor
  • Adjust upper control arm eccentrics
    • Front eccentric: moves camber & caster
    • Rear eccentric: mostly caster

Caster ~ Caster is what makes the car track straight.​

Target: +3.0° (or as much as you can get evenly)​

How to measure caster at home:​

  1. Turn wheel 20° left
  2. Read camber
  3. Turn wheel 20° right
  4. Read camber
  5. Your gauge will calculate caster OR you can use a simple online calculator

How to adjust:​

  • Rear eccentric OUT (toward the engine) → increases positive caster
  • Front eccentric IN → increases positive caster
Repeat until you get:

  • +2.5° to +3.5°
  • Both sides within 0.3° of each other

Re‑Set Camber ~ Caster changes camber, so now dial camber back in.​


Set Toe Using the String Method

Note: This is extremely accurate when done right.

Setup:​

  • Run a string down each side of the car at axle height
  • Make string parallel to rear wheels
  • Measure from string to front rim (front and back of rim)

Target:​

  • 1/16" total toe‑in (front of tires slightly closer together than rear)

How to adjust:​

  • Turn tie rods equally on both sides
  • Keep steering wheel centered

Center the Steering Wheel

Once toe is correct:
  • Adjust both tie rods evenly
  • Keep toe the same
  • Center the wheel


Thoughts?
 
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Front end alignment bolts....
When the washers are set to 12 oclock setting the arm neutral, is the bolt located at the 12 oclock (top) or the 6 oclock (bottom) of the washer?
 
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