Front end rebuild

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John Collins

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I’m setting up to rebuild the front end of my ‘73 Dart Sport. I bought a kit from Dr. Diff and added the idler and pitman arms. I’ve watched a ton videos, read multiple articles and have my service manual. The kit comes with pre pressed ball joints. Are there any potential pitfalls that any of y’all can think of? Kind of a last minute shout… I’m starting the work tomorrow morning. I felt good about my prep, but I just started feeling like I should ask the FABO community for insight before I get started in the morning.

5062993C-E582-43FB-BF91-10F560E4B203.jpeg
 
Looks like you've got rubber LCA bushings, so make sure you don't fully torque the LCA pivot pins until the suspension is at ride height (or pretty close to it). Hopefully you have a press or other means to remove the old LCA bushings and shells.

If your UCA's don't have Moog K7103 offset bushings, I would strongly recommend installing them before putting the whole front end together. At least if you're planning on running radials. With non-offset bushings you'll have a hard time getting the positive caster specs you'll want for radial tires.

It looks like you've got poly strut rod bushings. I'm guessing this is because the 73+ rubber strut rod bushings are still unobtanium, I know I haven't seen anything actually shipping on that front. The issue with poly strut rod bushings is they're frequently not the right thickness, which can push the LCA back and further hamper your changes at getting decent positive caster numbers. You can see one solution here... Cutting strut rod bushings for correct geometry?
 
If your UCA's don't have Moog K7103 offset bushings, I would strongly recommend installing them before putting the whole front end together. At least if you're planning on running radials. With non-offset bushings you'll have a hard time getting the positive caster specs you'll want for radial tires.
I’m not certain what’s installed. I’ll have to email Cass and ask. It doesn’t specify on the site which bushings come installed. I am running radials though.

Looks like you've got rubber LCA bushings, so make sure you don't fully torque the LCA pivot pins until the suspension is at ride height (or pretty close to it). Hopefully you have a press or other means to remove the old LCA bushings and shells.
Copy. Thank you.

I have a ball bearing press. I’m a little worried about removing the old bushings and shells without damaging the LCA too bad, but I know that in the end if I’m having too much trouble, I can take them to a local mechanic.

It looks like you've got poly strut rod bushings. I'm guessing this is because the 73+ rubber strut rod bushings are still unobtanium, I know I haven't seen anything actually shipping on that front. The issue with poly strut rod bushings is they're frequently not the right thickness, which can push the LCA back and further hamper your changes at getting decent positive caster numbers. You can see one solution here... Cutting strut rod bushings for correct geometry?

I didn’t know about this issue, thank you! Mine are the same thickness… I’ll cut one down, per your links instructions.

Thank you very much for the insight! Extremely helpful.
 
UCA ball joints are screwed in, not pressed.
if you look in the photo the UCA's are already assembled, he was talking about the LCA bushings that will need to be pressed out and pressed back in.
 
Just a quick alignment tip, set the upper control arm eccentrics so that you move the upper ball joint as far back as possible. This can be done by moving the front bushing so that the front is as far out (closest to fender) as possible and rear is as close to the engine as possible. The eccentrics should be opposite of each other when installed. Good luck.
 
Just a quick alignment tip, set the upper control arm eccentrics so that you move the upper ball joint as far back as possible. This can be done by moving the front bushing so that the front is as far out (closest to fender) as possible and rear is as close to the engine as possible. The eccentrics should be opposite of each other when installed. Good luck.
Thank you!
 
You can easily tell if you do or don't have the offset LCA bushings. Just LOOK at them. The center holes are offset from the center of the bushing, AKA the rubber is especially built for that purpose. As mentioned above, they should be offset in such a way as to give the upper joint the most rearward "tilt" if you were looking down on the arm from above. The front one should push the arm out away from the vehicle, and the rear bushing opposite
 
After pulling the front end, it became apparent that my rotors and rubber brake lines are shot. I have 16” Cragars. I’m looking at a set of 11.75” replacement disc brakes with new calipers from Doctor Diff for $600. After measuring, it seems like they’ll fit without issue. If not, do any of y’all have a suggestion for front disc brakes for a 1973 dodge dart sport with a mildly built (unknown build sheet) 360, but definitely not stock. I will be building another engine soon though(parts in hand) that’ll be a little bit beefier to replace this one when the time comes. Still nothing crazy. Probably a little shy of 400hp with 3.91 gears.

Thank you all again for the earlier support! I would’ve made a couple big missteps without it.
 
After pulling the front end, it became apparent that my rotors and rubber brake lines are shot. I have 16” Cragars. I’m looking at a set of 11.75” replacement disc brakes with new calipers from Doctor Diff for $600. After measuring, it seems like they’ll fit without issue. If not, do any of y’all have a suggestion for front disc brakes for a 1973 dodge dart sport with a mildly built (unknown build sheet) 360, but definitely not stock. I will be building another engine soon though(parts in hand) that’ll be a little bit beefier to replace this one when the time comes. Still nothing crazy. Probably a little shy of 400hp with 3.91 gears.

Thank you all again for the earlier support! I would’ve made a couple big missteps without it.

The 11.75’s will fit with a 15” rim, so a 16” should be fine. Cass (DoctorDiff) would probably know for sure for a popular wheel like that.
 
think everything has been mentioned except.

it is easy to lose a section of strut rod bushing into the hole in the k frame.
well i found it easy.. my K may differ from yours...

if it goes in it aint coming out unless you take off the K and upend it

block up top-side holes with rags while heaving bits of suspension about and avoid having buy another set :)

Dave
 
After pressing out the pins on my LCA’s, I decided to go with poly bushings and Greasable pins. I couldn’t figure out how to get the casings left behind out without damaging the LCA’s, or welding. I found one method that used a long jigsaw bit to cut a 3/8” wide section the length of the bushing out and then he chiseled the casing out. Seemed timed consuming and most likely I’d f up the LCA’s. The only local guy I could find who’d do it wanted $100 to weld and press the bushing casing out. I figured that the Greasable pin and bushing set was only a couple bucks more, so why not? I’ve prepped and painted everything that I’m reusing from my front brakes and the LCA’s… I’ll mask off and paint the new rotors to prevent future rusting. Now I’m just waiting on the last few bits and pieces(gaskets, seals, bearings, caliper piston, hardware…) should arrive Tuesday and then I’ll get the front end and brakes back together and installed.
 
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