Fuselage - Drums to Disc Brake Conversion

Just about to start this project. Have all my new rotors, pads, caliper rebuild kits, seals, hoses etc, and OEM calipers and spindles/brackets. Before I start pulling old parts off....is it absolutely necessary to replace the master cylinder and brake booster for a different style...designed for a disc brake setup? I thought I saw where it wasn't necessarily required, but I could be wrong. I currently have drums upfront, along with power booster/brakes. If I for sure need a different MS and booster, I'll have to wait before I start this project. I don't want to start pulling stuff apart, to find I in fact did need these two additional items. Thanks for any info!!
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Just about to start this project. Have all my new rotors, pads, caliper rebuild kits, seals, hoses etc, and OEM calipers and spindles/brackets. Before I start pulling old parts off....is it absolutely necessary to replace the master cylinder and brake booster for a different style...designed for a disc brake setup? I thought I saw where it wasn't necessarily required, but I could be wrong. I currently have drums upfront, along with power booster/brakes. If I for sure need a different MS and booster, I'll have to wait before I start this project. I don't want to start pulling stuff apart, to find I in fact did need these two additional items. Thanks for any info!!
I put ‘72 NY Disc brakes on my bro’s ‘66 300 and kept the original drum booster. It has always worked very well, although I know that a disc booster would be even better. But you can definitely use a good drum booster.
 
I recently did a disc brake conversion on my '67 fury III convertible, using a Wilwood conversion. The braking is splendid! I will also convert the rears to disc. Front spindles and wheel bearings remained the same, used the original spindles. The days of unequal braking are over, evidently.
 
When you jack it up, put the jack stands under the lower control arms (I like to use under the shock absorber) the weight of the car will hold it and you won't have to mess with the torsion bar adjustment. Then all you have to remove is the upper ball joint and the two bolts that hold the spindle to the lower ball joint.


I personally prefer to unload the spring (torsion bar) pressure altogether. If for some reason the spring gets to release its energy unexpectedly, you could lose an arm. NOT worth the risk, IMHO. Simply mark the bolt adjustment before loosening so's you can put it back exactly where it was.
 
I take it you have never worked on one of these from the rust belt. I have seen the torsion bar adjusters so frozen you had to heat them for 10 min. with a torch to get them to unload.

That is correct. A real CHORE, to be sure. After all that time in the rust belt, is there anything left of the rest of the car? I HATE winter salt.
 
Guys, if you need an option for a disc (dual diaphragm) booster my 69 fury uses this Cardone booster 54-73309 from a 75+ fury. Fits fine except the hole in the mounting bracket needs to be widened to fit the rubber cover and because its longer it interferes with a column shifter if you have that. My car was a power drum brake car so the booster linkage rod fits the pedal mount just fine. But manual pedals wont fit. When you are debating rebuilds and reusing old and chevy boosters consider this option also.
 
I personally prefer to unload the spring (torsion bar) pressure altogether. If for some reason the spring gets to release its energy unexpectedly, you could lose an arm. NOT worth the risk, IMHO. Simply mark the bolt adjustment before loosening so's you can put it back exactly where it was.
Remember on a Chrysler the torsion bars are the springs. Their is no way they can fly out under load, (unlike a coil spring).
 
Remember on a Chrysler the torsion bars are the springs. Their is no way they can fly out under load, (unlike a coil spring).

Well if the stand was under the LCA and the torsion bar broke, that could possibly cause a calamity as could separating the balljoint with the suspension hanging so the fail safe way would be to set a stand under the LCA at a height that allows the chassis to rest on a second stand when the jack is lowered.

Now the car can't fall should the torsion bar fail and the torsion bar can't unload violently if you separate the balljoint from the LCA.

Kevin
 
I recently did a disc brake conversion on my '67 fury III convertible, using a Wilwood conversion. The braking is splendid! I will also convert the rears to disc. Front spindles and wheel bearings remained the same, used the original spindles. The days of unequal braking are over, evidently.

What brake booster did you use? Perhaps you can answer to this threat and give us all more info Wilwood brakes on a C body

Thanks :thumbsup:
 
Rockauto seems to have the Raybestos 7012R rotor (fit for '69-'72) in stock again. Priced at $65.61 a piece. Bought a pair of them, for spares.
 
Guys, if you need an option for a disc (dual diaphragm) booster my 69 fury uses this Cardone booster 54-73309 from a 75+ fury. Fits fine except the hole in the mounting bracket needs to be widened to fit the rubber cover and because its longer it interferes with a column shifter if you have that. My car was a power drum brake car so the booster linkage rod fits the pedal mount just fine. But manual pedals wont fit. When you are debating rebuilds and reusing old and chevy boosters consider this option also.
That later booster sounds like an interesting option. I looked at the pics on Rock Auto and it appears to be a dual diaphragm. Wider single diaphragm boosters usually interfere with column shift linkage on slab-side C-bodies. How wide is the diameter of this booster? Thanks

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5473309-top__ra_p.jpg
 
At the crimp its 9-9.5 inches. A little less everywhere else. Like others disc boosters I still see "out of stock" and you must supply a core, I think the cores might be easier to find though. I did a little searching hoping to find them in vans, pickups, etc. But other than Furys and a Cordoba I did not see an application on RA. So I now am looking for parts cars to grab this booster for rebuild for others on the board. Here is a pic in my car (69) but because its all black its not as useful as it could be.

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I know this is not the tech forum, but I want to speak specifically to the fuselage crowd...and I have a feeling the answer will either be yes or no, LOL. I'm contemplating the drum to disc brake swap on my 70' Newport. It currently has 11" power drums all the way around. I know these were probably cool way back in 1970, and they still get the job done now ok. However there has been one or two times when I kinda would have liked discs up front....it came too close for comfort. I know there are complete kits out there that can be had to accomplish this, but I just saw nice brand name rotors at Rock Auto for $50 bucks a pop. I figure If I grab these, I could source everything else (calipers, pads, clips, new rubber brake hose..yada yada).
So then the BIG yea or nay question is can I keep my original spindles for the power disc brake set up??
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I've done several of these
On my 69 Polara I used a complete set from a 73 Cbody

I did not have power brakes so I kept the manual brake MC It worked fine not much extra pressure required, even My wife liked
I did have rear wheel lock up problems so I used the smaller wheel cylinders easy to interchange if you find a catalog with the wheel cylinder specs
On icy downhills the fronts would lock first making it hard to steer...even when pumping
Yes I should not have been going down that hill
I held the emergency brake release and used the emergency brakes to keep slow and steer at the same time variable pressure valve in front of drivers seat fixed not hard to find and plumb
chains on the rears
you will have to use 15" wheels
I used 15x7 PC wheels (on my Dakota I have 16x8 Durangos)
78 SW HD torsion bars, extra rear leaf Cordoba rear sway handled like a sprots car
front sway increase is tough
 
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