Upper Control Arms in Disc Conversion

I was relaying what I found on the "Big Block Dart" site. I never said that 10" drum brake 73 and up UCAs wouldn't work. All I said was that 73 and up A body disc brake control arms had the LBJ.
That's why I posted the links, so everyone could read it for themselves. I guess I should have said that the lower control arm is not an issue because you can keep that but you need the 73-76 lower control arm ball joint for the larger spindle. That's why I asked everyone to read the links.

PS - If 73 and up 10" drum brake upper control arms will also work in the swap then it leaves more options!!! Big Block Dark doesn't address the 10" drum brake upper control arms.
Treblig


Here is what the Big Block dart site says:


A-BODY DISC BRAKE CONVERSION

It's helpful to know the various chassis designations in order to find the correct parts.
Please refer to the Chassis Style page for more info

1. Upper Control Arms, from 1973-1976 A-Body Disc Brake Car. (single Piston Caliper only) The upper control arms are needed because the A-bodies were upgraded to the bigger B-body balljoints in 73, which means you need the later a-body arms to get the bigger balljoint. You can see the balljoint differences on the Steering Linkage Page

2. Spindles from 73-up A,B,E,F,J,M,R chassis disk brake car. Drum spindles don't work.
Note - the B,F,J,M,R spindle does have differences... Read A vs. B spindles for more info
3. Rotors and calipers - A-body rotors were 11" and were also used on many other cars. Some 77-79 B and 79-81 R bodies used an 11.75" rotor. Both rotors fit all spindles above. You do however need to use the caliper bracket that matches the rotor diameter. There are pin-type calipers and sliding calipers. The correct one must be used with the corresponding bracket. Most likely you'll find all your parts together on one car. The less-desirable pin-type calipers were used on the E-bodies, while most other cars had the slider style calipers.
4. Divider block and prop valve from a donor disc brake car.
5. New Front Brake Hoses (Rubber)
6. New Brake Pads & Bearings (you must know what make, model and year of the donor car)
7. New Master Cylinder, Disc & drum, use 73-76 A-Body, with or w/o power brakes
8. 4.5" bolt pattern front wheels.
9. New Upper Control Arm Bushings recommended
10. 73-76 Lower Ball Joints are necessary. The stock lower control arms can be retained.
11. From the donor car, remove the (2) lines that are attached to the master cylinder, and use them on
your car. it just easier to use these lines than to bend up your existing ones to work.



INSTALLATION:
1. Remove tension on Torsion Bars.
2. Replace the Upper Control Arms.
3. Replace Front Spindles with donor set, being careful not to mix up the left and right sides
(calipers to the front, steering arm/balljoint to the rear)
4. Install Proportion Valve in Line, in place of your old divider block
5. Replace Lower Ball Joints with 73-76 A-Body, (Larger size)
6. Install Rotors, Calipers and Pads
7. Replace Bearings, install cotter pin .
8. Re-Tighten Torsion Bar Adjuster to attain the proper ride height.
9. Install Master Cylinder. You will need a New Push-Rod Rubber Bushing, that holds the Pedal Push
Rod into the Rear of the Master Cylinder.
10. Have the front end Aligned -It's recommended you ask for the most caster possible while holding
factory camber settings.





As a final note, MANY of these cars interchanged alot of parts - almost everything was standardized from 73-up, so almost all the disc brake parts are interchangable, all based on rotor size 11" or 11.75"- for example, an '81 New Yorker 11.75" rotor can be used on a 73 Charger disc spindle with a caliper from a 73 Dart and a caliper adapter from a 77 Cordoba - the only consideration is that the caliper bracket must match the rotor size. You just need to think of the raw parts and not the whole car.

If you study through the tech pages, including the Moog Part # page, you'll find alot of similarities that will make your parts searches easier.