Fuselage - Drums to Disc Brake Conversion

Are the lower ball joints the same for drums and discs?
Yes and no. Bear with me on this, 1965 thru 1968 Disc brake ball joints are different, they had four mounting holes instead of two. 1969 thru 1973 drum brake lower ball joints are the same as disc brake ones, only two mounting holes.
 
Alright...I'm confused now: DO I need this pickle fork thing...(like the one samplingman or Detmatt have illustrated) or just a big hammer? Honestly I'm not crazy about wacking away at stuff under there with just a hammer...but if that's the best method so shall it be.

Parts list:
73' Disc brake spindles
Calipers (and related hardware)
New hydraulic disc brake hose(s)
Proportioning valve
Pwr disc brake MC (already have PWR brake booster, I can keep that?)
Brake Pads
Missing anything?

You will need to find a dual diaphragm disc brake booster. The single diaphragm one you have doesn't have enough boost to properly energize disc brakes. There are some that will say they kept the drum booster and it worked fine but in a panic stop situation you would find that to be less than true.

A 69-71 disc booster should work OK as they should be the dual diaphragm. I think in 72 they changed to a larger diameter single diaphragm that will physically bolt to the car but because it is bigger around, interferes with the column shift linkage. If you have a console shift it's not an issue.

69-71 300's and New Yorkers are good donors as they would most likely be disc brake equipped.

Kevin
 
Parts list:
73' Disc brake spindles
Calipers (and related hardware)
New hydraulic disc brake hose(s)
Proportioning valve
Pwr disc brake MC (already have PWR brake booster, I can keep that?)
Brake Pads
Missing anything?



Splash shields and their foam type gasket thingies? Not sure about Fusies.
Inner & outer wheel bearings
Qt. of brake fluid.
Cotter pin assortment.
Rust penetrate of your favorite flavor.
FCBO on speed dial...
 
My Fury, with factory disc brakes, has brass block splitting the single line from the equalizer block to the two front wheels. I asked why the big block and not just a smaller Y fitting and was told the block adjusted the output line pressure to equalize the braking force on each wheel. Don't know if drum braked cars use this block or not.

P9270008.JPG
 
You will need to find a dual diaphragm disc brake booster. The single diaphragm one you have doesn't have enough boost to properly energize disc brakes. There are some that will say they kept the drum booster and it worked fine but in a panic stop situation you would find that to be less than true.

A 69-71 disc booster should work OK as they should be the dual diaphragm. I think in 72 they changed to a larger diameter single diaphragm that will physically bolt to the car but because it is bigger around, interferes with the column shift linkage. If you have a console shift it's not an issue.

69-71 300's and New Yorkers are good donors as they would most likely be disc brake equipped.

Kevin
If you do have a counsel shift I have a rebuilt 72 master and booster never used. PM me if interested.
 
So, every one's first choice is to use MA mopar spindles and related parts, as outilized above. Would the ssbc performance brake packages be a second, for the reuse of the drum spindles? My Wagon has 15 inch rims so no spacers required
If this is not a good after market choice what do ye say is
 
I've read a lot of horror stories about SSBC kits. Well maybe horror is a strong word but I've not seen too many reviews that showed any more than mediocre performance compared to if you used the factory stuff. IMHO it's because they use good quality but mismatched components.

If I was going to use any non OEM kit it would be ECI. I met the owner at Carlisle years ago and was ribbing him about the GM parts he was using for a Mopar app and he gave me a sensible engineering based reason why and besides the obvious cost benefit, it boiled down to the GM calipers had bigger pistons than the Mopar ones so you didn't need to swap out the booster to make enough line pressure.

ECI Disc Brake Conversion Kits - Chrysler Products

My first choice would still be OEM disc spindles and parts.

When I did mine the splash shields from the donor car were FUBAR so my 66 has none. No ill effects that I've noticed.

Kevin
 
The SSBC C-body kits were popular because of the exorbitant expense of replacement rotors.
The $50 RockAuto rotors make the SSBC advantage moot.
And I will go to my grave with the belief the bearings aren't sized correctly.
 
it is the aluminum hubs, that have steered me away. I know billet aluminum is strong, just seems wrong in this application. Starting to pull parts together for my wagon project, the ssbc kit seemed one stop shop
 
Commando 1 and are in agreement on this, the factory updated parts yearly as needed. while the 1973 spindles are getting scarce, the 1972 spindles are plentiful and cheap, with the rotors going for $50.00 each the price is great, also I have a set on my 300 and they are reinforced like the newer ones. Why take the chance using non factory parts, when you can get factory engineered parts for a better price. Seems like a no brainer to me. I picked up a set of 1972 spindles for $45.00 each with the brackets and shipping. the total cost was $350.00 for everything. Can you get the SSBC kit for that price?
 
it is the aluminum hubs, that have steered me away. I know billet aluminum is strong, just seems wrong in this application. Starting to pull parts together for my wagon project, the ssbc kit seemed one stop shop

While the SSBC kit might be convenient, for the $800-$1200 they seem to think it's worth you could have a set of spindles shipped from the far side of the planet, buy the rest of the parts from Autozone and still have some change left over.

Something else to consider is rotor thickness. I looked at some of the kits SSBC offer and their rotors are only 11.25" in diameter and .8125" thick. If these are adequate for hauling down a 4-5000 lb C-body, why did the factory spec 11.75" x 1.25" thick rotors? Even their bux up $1500+ kit seems to be barely equal to OEM with a 13" x 1.13" rotor.

Kevin
 
Commando 1 and are in agreement on this, the factory updated parts yearly as needed. while the 1973 spindles are getting scarce, the 1972 spindles are plentiful and cheap, with the rotors going for $50.00 each the price is great, also I have a set on my 300 and they are reinforced like the newer ones. Why take the chance using non factory parts, when you can get factory engineered parts for a better price. Seems like a no brainer to me. I picked up a set of 1972 spindles for $45.00 each with the brackets and shipping. the total cost was $350.00 for everything. Can you get the SSBC kit for that price?
And one more thing I forgot to mention, I have worked for Chrysler and GM, GENERAL MOTORS BRAKE CALIPERS STINK, on Chrysler calipers you do not have to bend the tabs on the pads to keep them from rattling.
 
I will put my 2 cents.
SSBC stuff seems light duty for a C body AND if you drive your car away from convienent tow home you will be sitting in a hotel waiting for UPS man to deliver repair pieces.
Early stuff pre-70 you will be permanent resident at hotel waiting for those obsolete parts.
Biggest rotors, biggest calipers, easily available parts, that is the best.

That brass Y shaped valve in front line is a standoff valve it holds off application of front calipers allowing time for rear shoes to move toward drum mostly in low pressure gradual breaking in low traction conditions (snow/ice). You do not need it and it disappeared a few years later.
 
You will need to find a dual diaphragm disc brake booster. The single diaphragm one you have doesn't have enough boost to properly energize disc brakes. There are some that will say they kept the drum booster and it worked fine but in a panic stop situation you would find that to be less than true.

A 69-71 disc booster should work OK as they should be the dual diaphragm. I think in 72 they changed to a larger diameter single diaphragm that will physically bolt to the car but because it is bigger around, interferes with the column shift linkage. If you have a console shift it's not an issue.

69-71 300's and New Yorkers are good donors as they would most likely be disc brake equipped.

Kevin
So Im gonna need a new pwr brake booster as well? Can't use the one already on the car...its a "pwr" drum booster....makes no difference? Great...it's kind of tricky swapping out brake boosters from what I've seen others do.
 
Semi related question: I'm about to begin the tear down. The front end is gonna be up on jack stands (naturally)...so is it preferable to put the entire car up on jack stands or just the front end..or doesn't it really even matter? I'm inclined to put all four corners up.
 
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