F,M,J Body Brakes fit on an A-Body?

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There are a lot of folks who will tell you the modified angles that result from FMJ swap will cause bumpsteer and other problems. I have done two FMJ swaps, one on an early A and one on 70 and both worked out well with no negative issues.
 
Not trying to cause any problems here but I have a question. I have a 70 Dart with 10 inch manual drum brakes and I would like to use parts from a 88 Diplomat to convert to disk brakes. Keeping it manual brakes what parts from the Diplomat would have to get from it and what other parts would I have to buy? Any help would be greatly appreciated.
Ken
 
Spindles out... Prop valve

Leave the uppers as they do you no good.

Get a new master for a 73-76 A body with manual disc or same year B body.
 
Get an adjustable proportioning valve. It'll be easier to plumb in and offer tunability to your brake system.
 
So if I get the spindles, rotors, calipers and the brake hose that goes to the caliper I should be able to bolt it all up in my car (70 Dart) once I get the correct upper control arms and master cylinder. One more question would all this same hardware work from a 77 Cordoba?
 
70408dart said:
So if I get the spindles, rotors, calipers and the brake hose that goes to the caliper I should be able to bolt it all up in my car (70 Dart) once I get the correct upper control arms and master cylinder. One more question would all this same hardware work from a 77 Cordoba?
Click to expand...

get the spindles rotors and calipers; but assume all is a core and will likely need replacing; don't use the flex hoses buy new ones but make sure you take them off for reference

I believe cordoba are different (much larger)
 
your current lowers will work, no problem. You can use your small ball joint uppers if you get the BJ adapters from DrDiff.
 
Is this from a commercial yard?

If you're paying for parts, just grab the spindles, caliper brackets and prop valve. Leave the rotors unless they're in great shape and you're going to use them. Same for the calipers, the core charge at a lot of places is less than what they'll charge you at the yard. Worth checking into anyway, for me the core charge is about the same as the price of calipers at the yard, so unless you're going to use them its just a lot of lugging around nasty old calipers to end up even anyway.

If you can get parts off of a '77 Cordoba, HURRY, they go fast. That one will likely have 11.75" rotors, which will bolt right on if you grab the whole set up. Only thing is you have to run 15" wheels. Same deal otherwise, grab the spindles, caliper brackets and prop valve. Buy the rotors new and get a set of reconditioned stock calipers from the local parts store.
 
Thanks for all the info from everyone it will definetly be of help. The cars that will be used for parts are in a local U-Pull it salvage yard. I was there about a week and a half ago so hopefully they will still have it. The Cordoba had a big block in it. The Diplomat just a 318.
 
So I got the spindles off an 85 Diplomat today. (Police car 318 four barrel)
I know that I have to get the upper control arms that have the big ball joint but do I need different lower ball joints? What brake hoses are used in this conversion when using all the components (will be new M/C, rotors,calipers and pads) from the diplomat. Going to try and use the proportioning valve from the Diplomat as well.
 
Anybody at all know if there is a difference in the lower ball joint from a 70 Dart verses a 73 on up? And the spindles from a 85 Diplomat will they bolt right up or do I have to make any modifications?
 
I believe the lower ball joints are the same, unless your car had 9" drums. Either way, might not be a bad idea to replace them unless they've been recently replaced. You will need new bolts though, because the lower ball joints on the Diplomats were threaded, so they use shorter bolts than the A bodies.

The spindles don't need any modification. Brake hoses for a 73+ Dart with disk brakes should work fine.

And, you don't even really need to have the LBJ upper control arms. Dr. Diff sells an adaptor sleeve that allows you to use the small ball joint uppers with the disk spindles. He has them listed HERE
 
I had heard about the Dr. Diff adapters and now with your help know what they look like. I guess my big concern now is the lower ball joint. I've heard that I have to use the 73-76 lower ball joint. Not sure what the difference is. I wonder if the ball joint itself is larger like the top or the holes for the bolts are larger? All of my front end suspension is new with very little miles on them as my car made its first on the road trip around Sept of last year and now its apart again for some other stuff.
 
You need the 73-76 A body lower ball joints.

The earlier ball joints have a narrower spread of the attaching bolt holes.
 
Im doing the exact same thing on my 66. 87 gran fury spindles, hubs, new seals and bearings, caliper brackets, prop valve, (im using the rear axle as well, 11x2.5 drums, so the system is matched to the valve) 74 scamp upper arms, offset bushings, new eccentric bolts, C-body tie rod ends and adjuster sleeves, suprisingly they are literally half the price as early-a tie rods and sleeves, have the same exact taper, plus the C-body ones are bigger threads, 11/16 compared to 5/8. 73-76 lower ball joints, grade 8 bolts with castellated nuts and cotter pin holes drilled in the bolts to bolt together the M-body spindle to the 73-76 lower ball joint, steel piston calipers, 76 volare brake lines, 70-74 E or B body manual disc brake master cylinder, and im sure a bunch of other stuff....but thats what i have sofar!
 
crackedback said:
You need the 73-76 A body lower ball joints.

The earlier ball joints have a narrower spread of the attaching bolt holes.
Click to expand...

There you go!

I thought just the 9" drum lower ball joints were smaller, but I guess not. I've converted a couple cars, but all of mine needed the ball joints changed anyway so I just bought new ones for the 73-76 set up.
 
70408dart said:
Anybody at all know if there is a difference in the lower ball joint from a 70 Dart verses a 73 on up? And the spindles from a 85 Diplomat will they bolt right up or do I have to make any modifications?
Click to expand...

You want to use the lower ball joint for a 73-76 A body. Same part drum or disc for 73-76.
The spindles require no modifications.
 
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