10'' drum to disc brakes

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That depends on what car they're going on.

If they're going on a '74 Duster like your screen name, then no, you don't need to change the UCA's or ball joints. '73 up drum brake cars had large ball joint UCA's, just like the disk cars.

If they're going on a pre-'73 car, then yes, you need large ball joint UCA's and new ball joints OR a set of Dr. Diff's tapered ball joint adaptors.

And for what its worth, the small ball joint uppers look just like the large ball joint uppers on visual comparison. If you measure you can tell the difference in the size of the ball joint, but they're hard to tell apart visually.
 
72bluNblu said:
That depends on what car they're going on.

If they're going on a '74 Duster like your screen name, then no, you don't need to change the UCA's or ball joints. '73 up drum brake cars had large ball joint UCA's, just like the disk cars.

If they're going on a pre-'73 car, then yes, you need large ball joint UCA's and new ball joints OR a set of Dr. Diff's tapered ball joint adaptors.

And for what its worth, the small ball joint uppers look just like the large ball joint uppers on visual comparison. If you measure you can tell the difference in the size of the ball joint, but they're hard to tell apart visually.
Click to expand...

That may answer my quetion, I have a 73 manual drum Duster & want to run this kit

http://www.wilwood.com/BrakeKits/Br...ar=1973&make=Plymouth&model=A-Body&option=All

Kit states disc brake's so if the spindles are the same I should be fine. Will I need to the master cylinder as well? & if so can I just run the disc brake one?.
Cheers
 
74duster510 said:
thank you very much
would there be a cheaper way to do this?
Click to expand...

Absolutely. The kit you're looking at is all mopar parts, so you can get the at the local wrecking yard.

You can get all the parts except for the UCA's from an F/M/J car. Spindles, caliper brackets, calipers, rotors, etc.

You need:

LBJ UCA's (or ball joint sleeves from Dr. Diff)- you should have these already
73+ spindles, can be A body or F/M/J body
Caliper brackets for 10.87 or 11.75" rotors
Rotors, 10.87 or 11.75 (these will be large bolt pattern)
Calipers
disk/drum master cylinder
disk/drum distribution block/combo valve


You can get the spindles, caliper brackets, calipers and even rotors from a F/M/J body car, ie, Diplomat or 5th Ave etc all the way up to 1989, so those are usually available in the local yard.

Dr. Diff also now sells the 11.75" caliper brackets, which allow for the larger 11.75" rotors to be run (from Cordoba's, Volare's, Fury's etc) with the same stock calipers. Nice upgrade in stopping power, but you also need 15" rims to clear them.

Master cylinder, rotors, calipers, and rubber or braided brake lines are all best purchased new, the core charge usually isn't even enough to warrant pulling the used stuff from the yard. Just ask for stuff from a '74 Dart if you're using the 10.87 brakes, or a '77 Cordoba if you go 11.75".

Here's a list of cars with the right brakes. I've highlighted the ones that ran late, ie, the ones easiest to find in the yards. 5th Aves and Diplomat's are pretty common in the yards. The last set of Diplomat spindles/caliper brackets I bought at the yard were $60, might have been on sale, but you get the idea.

CHRYSLER CORDOBA (1975 - 1983)
CHRYSLER FIFTH AVENUE (1983 - 1989)
CHRYSLER IMPERIAL (1981 - 1983)
CHRYSLER LEBARON (1977 - 1981)
CHRYSLER NEW YORKER 1982
CHRYSLER TOWN & COUNTRY (1978 - 1981)
DODGE ASPEN (1976 - 1980)
DODGE CHALLENGER (1973 - 1974)
DODGE CHARGER (1973 - 1976)
DODGE CORONET (1973 - 1975)
DODGE DART (1973 - 1976)
DODGE DIPLOMAT (1977 - 1989)
DODGE MIRADA (1980 - 1983)
PLYMOUTH BARRACUDA (1973 - 1974)
PLYMOUTH CARAVELLE (1978 - 1985)
PLYMOUTH CUDA (1973 - 1974)
PLYMOUTH DUSTER (1973 - 1976)
PLYMOUTH FURY 1975
PLYMOUTH GRAN FURY (1982 - 1989)
PLYMOUTH SATELLITE (1973 - 1974)
PLYMOUTH SCAMP (1973 - 1976)
PLYMOUTH VALIANT (1973 - 1976)
PLYMOUTH VOLARE (1976 - 1980)
 
okay i swapped on some disc brakes today
the pads a fairly tight against the rotors why is this? they spin when i turn it manually with my hands but the pads are holding the rotor
do i NEED a new master cylinder and proportioning valve???
 
74duster510 said:
okay i swapped on some disc brakes today
the pads a fairly tight against the rotors why is this? they spin when i turn it manually with my hands but the pads are holding the rotor
do i NEED a new master cylinder and proportioning valve???
Click to expand...

Did you change the master cylinder or combination valve (distribution block)?

The master cylinder should be changed, but its not absolutely needed. I wouldn't run the drum master myself though, it really should be changed to a disk/drum master. BUT, the combination valve (the distribution block) has the residual pressure valves in it. Drums need about 10 psi of residual pressure, disks only need about 2 psi. So if you didn't change the distribution block over to a disk brake cars combo valve, you may have too much residual pressure.

If you DID change to a combo valve off a disk car, keep in mind that nothing pulls the disks off the rotor after the brakes are activated, the turning rotor just pushes them away a little bit. So after an install the pads may drag on the rotors as you turn them by hand. If the proper parts are installed though, this will go way if you drive the car. If you don't have the proper combo valve installed, they'll keep dragging.
 
I think it is normal for new pads to drag slightly until they seat to the rotor. I have read that what retracts caliper pistons is that the rubber pressure seal is square and rotates slightly as pressure is applied and released. Sounds hokey, but must work fine since I never heard of piston springs in any calipers.

The residual valve idea is good. There seems to be a lot of confusion about those, and I don't know all the answers. The purpose was to hold a little pressure on drum wheel cylinders so the rubber seals stayed tight and didn't draw in any air. I think I have seen where they were built into the ports of the MC and can be picked out with a tool. Maybe they were put in distribution blocks too, but not in my 64 or 65 since that part is just a 4-port "T". I have read that they weren't needed after they started using the "spring w/ 2 cups" in wheel cylinders or the "spring w/ wound cap ends". All wheel kits I have seen for years have those. You can buy after-market residual valves from race shops. I think those are just for custom rods where the MC is placed below the floor, at least I recall seeing that in Jegs catalog.
 
Thanks Blu i will let you know if it loosens up with pads a little when i get a combo valve
Other than that its stopping fine
Pedal only moves acouple inches now rather than going almost to the floor with the drums although that could have just been a bad bleed lol
 
Very cool! Thanks added for the parts list. I saved it and will be bringing it with me to the junk yard :D. I planned on buying new rotors and brake lines, will do the same with calipers if the price is right, but just to confirm (and not thread jack ;)) to go from an SBP to LBP set up I need:

Calipers/Lines/Rotors/large ball joints (all from parts store)
UCA's/spindles/brackets (junkyard)

missing anything?
 
Disk brakes don't free-wheel as easily as drums do, unless of course the drums are dragging the shoes.

But you can easily tell if the residual valve is the problem, AND you can remove it. Just jack up the front wheels, apply the brakes hard, and release, and let it sit for about 30 seconds. Then turn each front wheel and notice how difficult they turn.

Now take a pan, rag, etc, and loosen the flare nut on the master which leads to the front, see if any pressure is relieve, then re--check the front wheels. If they turn easier, then you need to yank the residual valve out of the 1/2 of the master feeding the front. Out of a shop manual:

Screw a small sheet metal screw into the center of the brass seat, and use a claw hammer, etc to pull the seat and valve out. Leave the guts of the valve out, and replace the seat, re--bleed the master at the fitting.

30j2vwo.jpg
 
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