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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Nothing they dont know about powee brakes
 
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

5473309-lef__ra_p.jpg


5473309-bot__ra_p.jpg


5473309-rit__ra_p.jpg


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??
View attachment 74511
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
 
OK, I gotta jump in here. It has been awhile since I posted, but I am not dead yet! It is racing season and I am busy making a living. But, in the downtime ,(LOL) I have been working on FURY-US. The 1967 Fury III that I am restoring for my wife. I went with the Wilwood 12" rotor and 6 piston caliper upgrade for the front of the Fury. Very nice kit and uses the stock spindle.

Now here is the kicker. I am planning on installing a Flaming River rack and pinion set up and loosing the stock steering box, pitman arm, idler arm and draglink. I think that this is very doable. I have mocked it up and the only problem I see is with the headers. This car will get a 600 HP 512 big block under the hood, so I need headers. I can fab them myself, but I am looking at aftermarket headers. I am thinking that the shorty type of headers will work, but I need to do more research before pulling the trigger on that. In the meantime, I have the rack and pinion mocked up and it looks pretty good.

What is you guys opinion? Feed back please!
Flaming River Rack & Pinion (1).JPG

Flaming River Rack & Pinion (2).JPG
Flaming River Rack & Pinion (3).JPG
 
That's gonna be a pretty serious U-joint angle into that R&P. Steeper angle than stock, and much closer to the column, too.
Is the rack unit rated for the weight of a full-size car?

Which shorty headers are you considering? If the Hedmans, be aware they are only 2.5" outlet, so you might not want that on 600hp.
OTOH, if you connected them to 3" headpipes it might not matter much with them being shortys.
Looking at the pics again, you'll need center-dump units, the input to the rack is right where most headers will be routed.
 
That's gonna be a pretty serious U-joint angle into that R&P. Steeper angle than stock, and much closer to the column, too.
Is the rack unit rated for the weight of a full-size car?

Which shorty headers are you considering? If the Hedmans, be aware they are only 2.5" outlet, so you might not want that on 600hp.
OTOH, if you connected them to 3" headpipes it might not matter much with them being shortys.
Looking at the pics again, you'll need center-dump units, the input to the rack is right where most headers will be routed.
I agree with you completely. They will need to be center dump. I have looked at quite a few different manufacturers, but really do not see anything that I can buy and bolt on and work. Some that might are not big enough to support 600 - 650 HP. Most likely I will just make them myself. As far as the steering angle, it will defiantly increase over stock, but one thing I do like about the flaming river unit is I can index it at any angle. This should be a big plus. Also I did talk to Flaming river about what I was trying to achieve here and this unit should handle the weight of the Fury with no problems. I have a friend with an old set of Doug's headers. I am going to use them as a templet and "cut & paste" until I have a working set of headers. Should be interesting. Hey, nothing ventured, nothing gained. Thanks for the feedback.
 
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
Do you remember what size it was? I know the A and B body crowd went with 13/16 cylinders and apparently that works very nicely over the stock 15/16 cylinders. But not sure if that'd be suitable for C bodies.
 
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