Disc brake conversion regarding lower ball joints

[70DartMike]

I have a set of single piston discs from a 75 Dart to put on my 70 Dart originally with 10" drums. I pulled the upper control arms, rotors, calipers, brake hoses, and lower ball joints just came with the setup when I pulled it. I was told I could use my original lower ball joints, but that I just needed to convert my upper control arms (with bigger ball joint) to make this setup work. Well, the holes and bolts on my lower ball joints are smaller than the ones on the spindle of the discs, so I obviously have to change the ball joints to be the ones that came with the discs, but the arms are shorter and hang lower than my original ones. Is this going to affect the way my steering linkage hooks up to them, or my steering at all? I'm confused.. I was told my lower ball joints would work.

 

[684mulas]

I did the same swap and changed lower ball joints. The lower ball joint is different from 72 and older to 73 and newer. I dont think you can modify the early style to work.

There is lots of information on this swap.

http://www.225.ca/tech/jstk003.htm

http://www.bigblockdart.com/techpages/dbconversion.shtml

http://www.moparts.org/Tech/Archive/brake/9.html

this is an especially good one:

http://www.moparaction.com/tech/archive/disc-main.html

 

[RedFish]

All the lower ball joints fit the same lower arm. You'll need the ball joints that go with the spindles. The spindle geometry changes some and the arm on the lower ball joints do too. Alignment will be required.

 

[70DartMike]

Awesome, thanks guys.

 

[AdamR]

To swap to the 73-76 disc brakes spindles on 67-72 A bodies you need 73-73 Upper control arms and ball joints aswell as the 73-76 lower ball joints.