65 Fury disc brake conversion advice

65FuryPaceCar

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I'd like to convert my 65 Sport Fury to disc brakes for drive ability and safety.
Does anyone make a "kit" or is there a known supplier who can provide the needed parts as a whole? I don't want to start piece-mealing it and end up with mid-matched parts requiring modification and resulting in a poorly balanced braking system.
Any advice is greatly appreciated.
 

Ross Wooldridge

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Hi there and Happy New Year.

I am a mild expert regarding this very swap so I hope I can help you. However, please remember that I am NOT a licensed expert, just a backyard guy who has had some experience and learned from the experience of many others. There may be errors or omissions in my information. Therefore, if you have questions or concerns, consult a qualified mechanic.

The swap I'm talking about is the SINGLE BEST UPGRADE you can do to your car. The information below will result in a well balanced and reliable braking system that is serviceable with parts available from any supplier like Rock Auto or the like.

Your concern about piecemealing parts together... all of the parts for this swap are available new or rebuilt from the parts store, with the exception of the actual spindle assembly. For that you need to find a 69-72 disc brake donor C body, or a 73 disc brake donor C body. Why the disctinction? The 73 Spindles only fit the 73 rotors. However, the 73 rotor is used in various applications right up into the 80s and are way more available and have some minor improvements, so if you can find a set of 73 spindles, that's the best option. I'm using 69-72 gear, and it works fabulously on both my 66 Town and Country wagon and my 66 Monaco.

Regarding kits - yes, there are kits out there from various manufacturers like Scarebird and Stainless Steel Brake Company etc. Most, from all reports, seem to work well. Some use proprietary (their own designed) parts like spindle adaptors etc, mainly to allow the use of commonly available Bowtie parts. Search around and look at reviews.

One point against them in my opinion is that none of them seem to address the issue if the power booster if yours is a power brake car. They all seem to say you can keep your existing drum brake booster.

WRONG. DANGEROUS.

The drum booster does not have enough power to fully energize the disc system in the event of a panic stop. Yes it will bolt up and work fine for 95% of your braking needs, but if that dumb kid on a bike cuts in front of you would you rather be able to have stopped before you ran them over or the 25 feet farther it takes with the wrong and weaker booster? My point is you don't want to find out the hard way.

So I always advise people doing this swap that you MUST use the correct Disc Brake booster when running a disc system swap.

The second point is I feel that many aftermarket systems use parts designed to work on lighter cars, and bearing spacers that leave me a little leery of their true ruggedness. Again, you don't want to find out the hard way.

Now - here's what I feel is the best option: Ma Mopar engineered a dandy disc system for our C bodies from 69 up to 73 that you can take advantage of...

All C body cars with disc brake systems from 69 to 73 use the same lower ball joint as the 65-68 C body cars with drum brakes. A big advantage, because all the disc brake hardware (spindles, calipers, backing plates etc) from the 69 and up cars BOLT RIGHT IN.

A DIRECT SWAP.

I am copying and pasting a bunch of documents on the swap - parts interchanging, donor lists, and what you need and how to do it.

There are a few caveats - if your car has column shift for example, there are a few C body boosters that may interfere with the column shift linkage. Cars with factory Autopilot will have fitment issues with the master cylinder...

Read on:

DISC BRAKE CONVERSION INFO FOR 65-68 C-BODY

FOR NON AUTOPILOT EQUIPPED CARS, ONE CAN USE ANY 69-73 C-BODY DUAL RES DISC BRAKE MASTER CYLINDER.

EDIT
IT IS ASSUMED THAT ONE WOULD SWITCH TO THE DUAL RESERVOIR MASTER CYLINDER FROM THE ORIGINAL SINGLE POT MASTER.
DON'T EVEN THINK ABOUT KEEPING A SINGLE RES MASTER...

FOR AUTOPILOT EQUIPPED CARS, USE MASTER CYLINDER NUMBER 1475.

THIS MASTER HAS A CASTING NUMBER 2226 821 ON THE BOTTOM, ORIGINAL APPLICATION 1968 CHARGER WITH DISC/DRUM, 10” REAR BRAKES. IT IS NICE AND SKINNY, AND THE BIG PLUS IS THAT IT HAS OUTLETS ON THE PASSENGER SIDE, AND WON’T INTERFERE WITH THE AUTOPILOT CONTROL HEAD MOUNTING BRACKETS. YOU WILL HAVE TO RE-FORM THE AUTOPILOT THROTTLE ARM AROUND THE MASTER, AND NOTCH THE TOP EDGE OF THE BRACKET TO CLEAR THE MASTER CYLINDER COVER. THERE IS ANOTHER MASTER SUBSTITUTED FOR THE SAME NUMBER WITH OUTLETS ON BOTH SIDES, WITH THE DRIVERS SIDE ONES PLUGGED. IT IS MUCH WIDER, AND WILL STILL INTERFERE WITH AUTOPILOT BRACKETS. MAKE SURE THE ONE YOU GET HAS THE CORRECT CASTING NUMBER ON THE BOTTOM.

USE 65-68 C-BODY DISC BRAKE BENDIX DUAL DIAPHRAGM BOOSTER.

FOR COLUMN SHIFT CARS, ONE MUST USE THIS BOOSTER TO AVOID BOOSTER INTERFERENCE WITH THE COLUMN SHIFT LINKAGE. THE BENDIX DUAL DIAPHRAGM BOOSTER FOR 65-68 DISC BRAKE C BODY CARS LOOKS LIKE THIS:

772904.jpg


IF YOU HAVE CONSOLE SHIFT OR FOURSPEED, YOU CAN USE ANY 65-73 DISC BOOSTER. DON'T USE THE DRUM BRAKE BOOSTER, AS IT DOES NOT HAVE ENOUGH BOOST TO COMPLETELY ENERGIZE DISCS, AND WILL LEAVE YOU WITHOUT ENOUGH STOPPING POWER IN AN EMERGENCY....JUST WHERE YOU NEED IT! YES, I KNOW SOME HAVE USED THE DRUM BOOSTER, AND YES IT WORKS, BUT THE FACTORY DID USE A DIFFERENT BOOSTER, AND FOR GOOD REASON.

EDIT
MORE NOTES ABOUT THE BOOSTER SWAP...

IF YOU ARE SWITCHING TO A DISC BOOSTER FROM AN EXISTING DRUM BRAKE BOOSTER, AND YOU ARE NOT REQUIRED TO USE THE DUAL DIAPHRAGM BOOSTER ABOVE BECAUSE YOU DON'T HAVE COLUMN SHIFT, THEN YOU CAN USE ANY OF THE DISC BRAKE BOOSTERS OFFERED ON C BODY CARS FROM 69 - 73. BOOSTERS WERE OFFERED IN BOTH DUAL AND SINGLE DIAPHRAGM CONFIGURATIONS DEPEDING ON THE YEAR AND VENDOR (BENDIX OR KELSEY-HAYES).

EDIT CONTINUED:
THERE MAY BE SMALL FITMENT ISSUES WITH THE SUPPORT PLATE THAT BOLTS TO THE FIREWALL BEHIND THE BOOSTER. I HAVE HEARD OF SOME ISSUES AND THE NEED TO OPEN UP CERTAIN HOLES IN THE PLATE TO PERMIT A DIFFERENT BOOSTER. I PERSONALLY DID NOT HAVE THOSE ISSUES BECAUSE I USED THE 65-68 DISC BOOSTER ABOVE ON MY CARS BOTH OF WHICH ARE 66s.

USE 69-73 C-BODY PROP VALVE.

RE-USE REAR HARD LINE FROM PROP VALVE.

MAKE NEW HARD LINES FROM MASTER CYLINDER TO PROP VALVE.

MAKE NEW OR RE-FORM FRONT HARD LINES FROM PROP VALVE TO FRONT FLEX LINES.

USE NEW FRONT FLEX LINES FOR 69-73 C-BODY WITH DISCS.


USE 69-72 DISC BRAKE SPINDLES, 69-73 CALIPERS, BACKING PLATES, SHIELDS AND HARDWARE.

USE YOUR EXISTING 65-73 DRUM BRAKE BALL JOINTS.


OPTIONAL: REPLACE EXISTING SPINDLES WITH 1973 C-BODY SPINDLES TO BE ABLE TO USE THE 1973 ROTORS AND BEARINGS. APPARENTLY THESE ROTORS ARE MORE AVAILABLE DUE TO USE IN VANS ETC UP TO MID 80’S

73 ROTORS AND BEARINGS CAN ONLY BE USED WITH 1973 SPINDLES.

The 73 rotor numbers are:
Raybestos PG Plus line - 7018
Raymold line - 107018
Aimco line - 7018RGS
Bendix - 141072

The 73 bearings are:
Inner - BCA - A17
Outer - BCA - A16


69-72 ROTORS AND BEARINGS CAN BE USED ON ANY C-BODY DISC BRAKE SPINDLE 69-72.
69-72 DISC BRAKE SPINDLES CAN BE SWAPPED INTO ANY 65-73 DRUM BRAKE C-BODY TO FACILITATE THE DISC CONVERSION, USING THE ORIGINAL DRUM BRAKE UPPER AND LOWER BALL JOINTS.
It is recommended that one replace used ball joints with new ones.

The 69-72 rotor numbers are:
Raybestos PG Plus - 7012
Bendix - 141047
The 69-72 bearings are:
Inner - BCA - A6
Outer - BCA - A2
The calipers are identical 69-73.

In general you want a smaller master cylinder bore to reduce brake pedal effort. If you care about the pedal effort I would look for the smallest bore disc brake master cylinder.
According to The Rock, 67-70 disc brake C-body cars had a 1 1/8' bore master cylinder while 71-73 disc brake C-body cars had a 1 1/32" master cylinder bore.
 
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Ross Wooldridge

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Here are some instructions:

1965-71 Newport, Polara, Fury, Monaco, New Yorker

Front Disc brake conversion instructions



1. Crack front wheel nuts loose, chock up rear wheels. Use all safety precautions.

2. Jack up front end of car, support outer lower control arms with jackstands.

3. Remove front wheels, drum/hub assembly.

4. Disconnect brake flexible line at frame by unscrewing hardline nut, then removing clip. Undo lower ball joint nuts, and remove bolts. Remove drum backing plate and all drum hardware in one assembly. Clean off spindle assembly

5. Place adapter plate on spindle with caliper opening to the rear. Reinsert bolts and torque to spec. We mark the heads of the lower bolt with a line to show cotter hole orientation before we insert them back into the spindle/ball joint.

6. Clean and repack same wheel bearings. Install new seal. Place supplied spacer onto spindle stub with inner taper facing toward spindle. Assemble rotor onto spindle, tighten outer nut to spec, then secure with keeper, new cotter pin and dustcap.

7. Wipe down rotor with alcohol, lacquer thinner or other cleaner to remove grease and oils.

8. Wash hands! Rotor must be squeaky clean

9. Install loaded caliper, and lube contact areas with silicone grease then screw in new slide pins, tighten to 35 foot-pounds. Make sure bleed screws are facing up as shown in illustration. Check fitment and rotate rotor to check clearance.

10. .Install new hoses with new copper crush washer, first to caliper, then insert other end into hose bracket on frame and secure with clip. Reconnect to hard line. Master cylinder and proportioning valve specs are quite varied. I would recommend 1976 Cordoba or similar disc master cylinder for best performance match for 65-68 cars, and use the stock disc master for later vehicles. Some have used the existing single chamber master cylinder with success- but be wary of fluid level: if you run out, you don’t stop or even slow down!

11. Bench bleed disc master cylinder, mount on car, then gravity bleed first, then pressure/pump bleed entire system and test. Break in new pads by 30 stops from 30MPH, with 30 seconds cooling between stops.

clip_image002.jpg
clip_image004.jpg


Parts List


Part Application NAPA Wagner Raybestos Cardone

Rotor (2) 1969-71 Fury 85558 BD60418 7018 --------------

Caliper, LH 1970-73 Fury 242-3000 CR76790 RC4062 164032

Caliper, RH 1970-73 Fury 242-3001 CR76791 RC4061 164031

Disc Pads 1970-73 Fury TS781 D39 PGD39R --------------

Caliper bolt 1970-73 Fury 82202 -------------- H50052 --------------

Brake Hose 1960 New Yorker front 24058 F26959 BH24058 --------------

Rotor Seal 1970-73 Fury 17110 SKF 17110 SKF 17110
 

65sporty

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Very well compiled info, I just looked and rock auto is out of stock of the 69 rotors. Aren't these the rotors that weren't made by the aftermarket previously until now? I thought that is what made the 73 setup the holy grail for disc brake swaps? I will be looking into this swap for sure. Thanks for your research.:)
 

traintech55

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Thank you Ross for your great expiation on this. This is a fantastic article and exactly what I did on my 66 300.
 

BigFury

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Same here, except I used the '73 factory vacuum booster. Had to call Murray Park for a '65 power booster mounting plate and pedal. I'm real pleased with the whole upgrade.
 

mopar_4life

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Hi there and Happy New Year.

I am a mild expert regarding this very swap so I hope I can help you. However, please remember that I am NOT a licensed expert, just a backyard guy who has had some experience and learned from the experience of many others. There may be errors or omissions in my information. Therefore, if you have questions or concerns, consult a qualified mechanic.

The swap I'm talking about is the SINGLE BEST UPGRADE you can do to your car. The information below will result in a well balanced and reliable braking system that is serviceable with parts available from any supplier like Rock Auto or the like.

Your concern about piecemealing parts together... all of the parts for this swap are available new or rebuilt from the parts store, with the exception of the actual spindle assembly. For that you need to find a 69-72 disc brake donor C body, or a 73 disc brake donor C body. Why the disctinction? The 73 Spindles only fit the 73 rotors. However, the 73 rotor is used in various applications right up into the 80s and are way more available and have some minor improvements, so if you can find a set of 73 spindles, that's the best option. I'm using 69-72 gear, and it works fabulously on both my 66 Town and Country wagon and my 66 Monaco.

Regarding kits - yes, there are kits out there from various manufacturers like Scarebird and Stainless Steel Brake Company etc. Most, from all reports, seem to work well. Some use proprietary (their own designed) parts like spindle adaptors etc, mainly to allow the use of commonly available Bowtie parts. Search around and look at reviews.

One point against them in my opinion is that none of them seem to address the issue if the power booster if yours is a power brake car. They all seem to say you can keep your existing drum brake booster.

WRONG. DANGEROUS.

The drum booster does not have enough power to fully energize the disc system in the event of a panic stop. Yes it will bolt up and work fine for 95% of your braking needs, but if that dumb kid on a bike cuts in front of you would you rather be able to have stopped before you ran them over or the 25 feet farther it takes with the wrong and weaker booster? My point is you don't want to find out the hard way.

So I always advise people doing this swap that you MUST use the correct Disc Brake booster when running a disc system swap.

The second point is I feel that many aftermarket systems use parts designed to work on lighter cars, and bearing spacers that leave me a little leery of their true ruggedness. Again, you don't want to find out the hard way.

Now - here's what I feel is the best option: Ma Mopar engineered a dandy disc system for our C bodies from 69 up to 73 that you can take advantage of...

All C body cars with disc brake systems from 69 to 73 use the same lower ball joint as the 65-68 C body cars with drum brakes. A big advantage, because all the disc brake hardware (spindles, calipers, backing plates etc) from the 69 and up cars BOLT RIGHT IN.

A DIRECT SWAP.

I am copying and pasting a bunch of documents on the swap - parts interchanging, donor lists, and what you need and how to do it.

There are a few caveats - if your car has column shift for example, there are a few C body boosters that may interfere with the column shift linkage. Cars with factory Autopilot will have fitment issues with the master cylinder...

Read on:

DISC BRAKE CONVERSION INFO FOR 65-68 C-BODY

FOR NON AUTOPILOT EQUIPPED CARS, ONE CAN USE ANY 69-73 C-BODY DUAL RES DISC BRAKE MASTER CYLINDER.

FOR AUTOPILOT EQUIPPED CARS, USE MASTER CYLINDER NUMBER 1475.

THIS MASTER HAS A CASTING NUMBER 2226 821 ON THE BOTTOM, ORIGINAL APPLICATION 1968 CHARGER WITH DISC/DRUM, 10” REAR BRAKES. IT IS NICE AND SKINNY, AND THE BIG PLUS IS THAT IT HAS OUTLETS ON THE PASSENGER SIDE, AND WON’T INTERFERE WITH THE AUTOPILOT CONTROL HEAD MOUNTING BRACKETS. YOU WILL HAVE TO RE-FORM THE AUTOPILOT THROTTLE ARM AROUND THE MASTER, AND NOTCH THE TOP EDGE OF THE BRACKET TO CLEAR THE MASTER CYLINDER COVER. THERE IS ANOTHER MASTER SUBSTITUTED FOR THE SAME NUMBER WITH OUTLETS ON BOTH SIDES, WITH THE DRIVERS SIDE ONES PLUGGED. IT IS MUCH WIDER, AND WILL STILL INTERFERE WITH AUTOPILOT BRACKETS. MAKE SURE THE ONE YOU GET HAS THE CORRECT CASTING NUMBER ON THE BOTTOM.

USE 65-68 C-BODY DISC BRAKE BENDIX DUAL DIAPHRAGM BOOSTER.

FOR COLUMN SHIFT CARS, ONE MUST USE THIS BOOSTER TO AVOID BOOSTER INTERFERENCE WITH THE COLUMN SHIFT LINKAGE. THE BENDIX DUAL DIAPHRAGM BOOSTER FOR 65-68 DISC BRAKE C BOY CARS LOOKS LIKE THIS:

NWMDC


IF YOU HAVE CONSOLE SHIFT OR FOURSPEED, YOU CAN USE ANY 65-73 DISC BOOSTER. DON'T USE THE DRUM BRAKE BOOSTER, AS IT DOES NOT HAVE ENOUGH BOOST TO COMPLETELY ENERGIZE DISCS, AND WILL LEAVE YOU WITHOUT ENOUGH STOPPING POWER IN AN EMERGENCY....JUST WHERE YOU NEED IT! YES, I KNOW SOME HAVE USED THE DRUM BOOSTER, AND YES IT WORKS, BUT THE FACTORY DID USE A DIFFERENT BOOSTER, AND FOR GOOD REASON.

USE 69-73 C-BODY PROP VALVE.

RE-USE REAR HARD LINE FROM PROP VALVE.

MAKE NEW HARD LINES FROM MASTER CYLINDER TO PROP VALVE.

MAKE NEW OR RE-FORM FRONT HARD LINES FROM PROP VALVE TO FRONT FLEX LINES.

USE NEW FRONT FLEX LINES FOR 69-73 C-BODY WITH DISCS.


USE 69-72 DISC BRAKE SPINDLES, 69-73 CALIPERS, BACKING PLATES, SHIELDS AND HARDWARE.

USE YOUR EXISTING 65-73 DRUM BRAKE BALL JOINTS.


OPTIONAL: REPLACE EXISTING SPINDLES WITH 1973 C-BODY SPINDLES TO BE ABLE TO USE THE 1973 ROTORS AND BEARINGS. APPARENTLY THESE ROTORS ARE MORE AVAILABLE DUE TO USE IN VANS ETC UP TO MID 80’S

73 ROTORS AND BEARINGS CAN ONLY BE USED WITH 1973 SPINDLES.

The 73 rotor numbers are:
Raybestos PG Plus line - 7018
Raymold line - 107018
Aimco line - 7018RGS
Bendix - 141072

The 73 bearings are:
Inner - BCA - A17
Outer - BCA - A16


69-72 ROTORS AND BEARINGS CAN BE USED ON ANY C-BODY DISC BRAKE SPINDLE 69-72.
69-72 DISC BRAKE SPINDLES CAN BE SWAPPED INTO ANY 65-73 DRUM BRAKE C-BODY TO FACILITATE THE DISC CONVERSION, USING THE ORIGINAL DRUM BRAKE UPPER AND LOWER BALL JOINTS.
It is recommended that one replace used ball joints with new ones.

The 69-72 rotor numbers are:
Raybestos PG Plus - 7012
Bendix - 141047
The 69-72 bearings are:
Inner - BCA - A6
Outer - BCA - A2
The calipers are identical 69-73.

In general you want a smaller master cylinder bore to reduce brake pedal effort. If you care about the pedal effort I would look for the smallest bore disc brake master cylinder.
According to The Rock, 67-70 disc brake C-body cars had a 1 1/8' bore master cylinder while 71-73 disc brake C-body cars had a 1 1/32" master cylinder bore.


I know that your saying that the dual-diaphragm is better(I fully agree) I have a full set up from a 71, minus the booster. Could I just use the booster from a disc/drum set up it says its a single on rockauto. Its listing the disc/disc as a dual diaphragm.

A-1 CARDONE 5473700 Reman. Vacuum Power Brake Booster w/o Master Cylinder Info
Front Disc brakes; Rear Drum brakes; with Single Diaphragm Booster

Or would that not be enough to stop the car? I don't want to gamble with the brakes.
 

cantflip

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10. Some have used the existing single chamber master cylinder with success- but be wary of fluid level: if you run out, you don’t stop or even slow down!
Excellent information... 1 1/2 cautions/corrections... + 1 addition...
The line quoted above... Don't Even Think About It!... with all that work, you need the dual master, PERIOD.
Ross, I think you're under control... but it's the internet... somebody might actually think they want to do this for some unfathomable reason.

This is the half...
Same here, except I used the '73 factory vacuum booster. Had to call Murray Park for a '65 power booster mounting plate and pedal. I'm real pleased with the whole upgrade.
There is a good chance the pedal will be different to provide proper leverage.

I started off very against mix and match brake swaps and the aftermarket companies don't have spotless records either. I do see the reasoning for this and have seen some decent swaps go on here... I am not an engineer. When you do this you have become the engineer, make sure the details are right.

Here is the addition... no mechanic or parts person will ever figure out what you have done, they wont even take the time to try. Document every single part by the year and model it came from and also the part number you used... that cross reference may help a ton in future years. I like a book, 3 ring binders and page protectors work great, to document everything that is ever changed from factory on the car. Make sure this stays with the car when you pass it on to the next owner... even make a copy for the trunk for road emergencies.
 

Ross Wooldridge

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65Sporty, I'm not sure about current availability of the 69-72 rotors... for my first swap I got NOS ones from National Moparts in Beaverton Ontario a number of years ago, and most recently I got a pair of LH NOS ones from another vendor courtesy of National Moparts who didn't have them in stock at the time. Keep your eye out - they're out there. I knocked the LH studs out of one and put RH thread ones in.

Thanks for the kind comments people - I have made edits to my first post regarding the various points raised - re-read if you're interested.

The edits I covered are:

1) USE A DUAL RESERVOIR MASTER CYLINDER - Can't FLip is entirely correct. I didn't even think that anyone would choose not to upgrade, but I guess I should've not assumed that.

2) YOU CAN USE ANY C BODY DISC BRAKE BOOSTER BOTH SINGLE AND DUAL DIAPHRAGM IF YOU DON'T HAVE COLUMN SHIFT - Mopar 4 Life, simple rule of thumb, if it doesn't say it's for disc, then don't use that booster. EDIT - I looked at the link for that booster and it's fine. For ehat it's worth, in 1969 there was a mid-year change from the Bendix dual diaphragm disc booster to the Kelsey Hayes single.

If your car is 69 and up you're good but if it's a 65-68 you need to take into account that if you have column shift, certain boosters (mainly the wider single diaphragm disc boosters like the one you're considering) will have clearance issues with the column shift linkage.

3) THERE MAY BE SLIGHT FITMENT ISSUES WITH BOOSTERS AND THE BOOSTER SUPPORT PLATE BEHIND IT.

Can't Flip is spot on about keeping detailed records about the parts used and where they came from, and also to pass that information on to future owners.

As well, my information really covers my experience with power brake cars. I do not have experience doing the swap with a manual brake car, but I do know that the pedal sets are very different in regards to leverage applied, and I do not recommend converting a manual brake car to a power brake car (or vice versa) unless you install the correct corresponding brake pedal.

Ultimately, to do a disc conversion on a manual brake car, the same sensibilities apply:

USE THE CORRECT DUAL RES DISC MASTER CYLINDER (I.E. 69 and up manual disc C body dual res master - I expect, but can't guarantee, that it will bolt up to your manual brake 65-68 firewall support plate, perhaps with minimal modifications to the plate.

USE A GOOD USED OR NEW METERING VALVE, OR GOOD AFTERMARKET ADJUSTIBLE VALVE

ASK LOTS OF QUESTIONS OF QUALIFIED PERSONS. DON'T GUESS AND DON'T TAKE SHORTCUTS.

Brake failures tend to let you down AT THE WORST POSSIBLE MOMENT. Plan accordingly when working on brakes. I had a licensed mechanic do the install on my first conversion, and helped me and checked my work on the second.


Think about this: Let's say for some reason you do a botched conversion (using an aftermarket kit that fails for example), and you are involved in an accident that kills or maims someone, and the investigation reveals that your brakes were faulty, and it's asked if you did the work yourself and you're not a licensed mechanic? The lawyers would have a field day...

This is anothe reason why I really like to use Mopar factory engineered parts. They tend to work really well together...
 
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cantflip

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65Sporty, I'm not sure about current availability of the 69-72 rotors... for my first swap I got NOS ones from National Moparts in Beaverton Ontario a number of years ago, and most recently I got a pair of LH NOS ones from another vendor courtesy of National Moparts who didn't have them in stock at the time. Keep your eye out - they're out there. I knocked the LH studs out of one and put RH thread ones in.

Thanks for the kind comments people - I have made edits to my first post regarding the various points raised - re-read if you're interested.

The edits I covered are:

1) USE A DUAL RESERVOIR MASTER CYLINDER - Can't FLip is entirely correct. I didn't even think that anyone would choose not to upgrade, but I guess I should've not assumed that.

2) YOU CAN USE ANY C BODY DISC BRAKE BOOSTER BOTH SINGLE AND DUAL DIAPHRAGM IF YOU DON'T HAVE COLUMN SHIFT - Mopar 4 Life, simple rule of thumb, if it doesn't say it's for disc, then don't use that booster. I would venutre to guess that a booster for a disc/drum set up would be fine, whether it is a dual or single diaphragm booster. Just take into account if you have column shift that certain boosters (mainly the wider single diaphragm disc boosters) will have clearance issues with the column shift linkage.

3) THERE MAY BE SLIGHT FITMENT ISSUES WITH BOOSTERS AND THE BOOSTER SUPPORT PLATE BEHIND IT.

Can't Flip is spot on about keeping detailed records about the parts used and where they came from, and also to pass that information on to future owners.

As well, my information really covers my experience with power brake cars. I do not have experience doing the swap with a manual brake car, but I do know that the pedal sets are very different in regards to leverage applied, and I do not recommend converting a manual brake car to a power brake car (or vice versa) unless you install the correct corresponding brake pedal.

Ultimately, to do a disc conversion on a manual brake car, the same sensibilities apply:

USE THE CORRECT DUAL RES DISC MASTER CYLINDER (I.E. 69 and up manual disc C body dual res master - I expect, but can't guarantee, that it will bolt up to your manual brake 65-68 firewall support plate, perhaps with minimal modifications to the plate.

USE A GOOD USED OR NEW METERING VALVE, OR GOOD AFTERMARKET ADJUSTIBLE VALVE

ASK LOTS OF QUESTIONS OF QUALIFIED PERSONS. DON'T GUESS AND DON'T TAKE SHORTCUTS.

Brake failures tend to let you down AT THE WORST POSSIBLE MOMENT. Plan accordingly when working on brakes. I had a licensed mechanic do the install on my first conversion, and helped me and checked my work on the second.


Think about this: Let's say for some reason you do a botched conversion (using an aftermarket kit that fails for example), and you are involved in an accident that kills or maims someone, and the investigation reveals that your brakes were faulty, and it's asked if you did the work yourself and you're not a licensed mechanic? The lawyers would have a field day...

This is anothe reason why I really like to use Mopar factory engineered parts. They tend to work really well together...
:thumbsup:Thank you sir, I believe you have made the best summary for one of these conversions I've seen so far. For anyone else who is thinking about this... there are a lot of threads on the subject in here... some of them are pretty darn good too.

If you watch the dates, you may even notice my evolution from "don't do it" to "proceed with caution"
 

saylor

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this was so well written, i was waiting for the sales pitch at the end... glad it never happened :)

so a couple of things to talk about -

1.) MC piston diameter. im thinking a smaller diameter piston makes a harder pedal. larger piston dia. = softer pedal.

2.) single v. dual booster applying more brake pressure than the other. I disagree. it may HELP you put pressure easier/faster, but the amount of hydraulic pressure in the line doesnt magically increase. try to apply brakes with NO booster you you will get what im saying.

all in all, thanks for the article. while several of us have done a brake swap/conversion, and several of us have documented it here on this forum, none are as concise and as focused as this.

try not to die -

- saylor
 

BigFury

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I know that your saying that the dual-diaphragm is better(I fully agree) I have a full set up from a 71, minus the booster. Could I just use the booster from a disc/drum set up it says its a single on rockauto. Its listing the disc/disc as a dual diaphragm.

A-1 CARDONE 5473700 Reman. Vacuum Power Brake Booster w/o Master Cylinder Info
Front Disc brakes; Rear Drum brakes; with Single Diaphragm Booster

Or would that not be enough to stop the car? I don't want to gamble with the brakes.
From the info I gathered while doing this very job on my car in Sept. was that it's much better to use the vacum booster. Which is why I had to call Murray to get a plate and a '65 power brake pedal. He charged me $75 for those parts. Which I felt was fair.
 

Ross Wooldridge

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Thanks again for everyone's positive comments, respectful corrections and helpful tips. This is what makes for an excellent community.

Saylor, as I inderstand it, typically in hydraulics the ratio between master cylinder bore and pedal pressure is counter-intuitive... so if I've got it right, a smaller bore has, to a point, the same result as lengthening the brake pedal arm - I.E. a longer lever and moving the load is easier.

As well, regarding the differences between dual and single diaphragm DISC BRAKE boosters - I agree with you. People considering this swap need to know that there is no difference between the single and dual diaphragm booster in terms of function and it is what fits best for them in their engine bay. There's no real discernable difference between the single and dual diaphragm boosters functionally. All of the disc boosters suitable for this swap are effectively identical in function and performance.

As I see it, the differences occurred primarily as the engine bays evolved and the bean counters watched. Likely the most compelling reason for the change from the dual diaphragm Bendix disc booster the the Kelsey-Hayes one was cost and fitment. The Bendix is longer and skinnier, putting the master farther out from the firewall, getting in the way of stuff like Autopilot and charcoal canisters, hot air stove tubes and othe bits that were starting to crop up. The issue was definitely aggravated by the fact the master cylinder was now a dual res unit and longer itself. The Kelsey Hayes single diaphragm unit is much wider and shorter, making that assembly less intrusive into valuable space underhood. Add to that the bean counter's cost savings in selecting a booster that has less moving parts in it and it's a win win for the profit margin.
 
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cantflip

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Thanks again for everyone's positive comments, respectful corrections and helpful tips. This is what makes for an excellent community.

Saylor, as I inderstand it, typically in hydraulics the ratio between master cylinder bore and pedal pressure is counter-intuitive... so if I've got it right, a smaller bore has to a point the same result as lengthening the brake pedal arm - I.E. a longer lever and moving the load is easier.

As well, regarding the differences between dual and single diaphragm DISC BRAKE boosters - I agree with you. People considering this swap need to know that there is no difference between the single and dual diaphragm booster in terms of function and it is what fits best for them in their engine bay. There's no real discernable difference between the single and dual diaphragm boosters functionally. All of the disc boosters suitable for this swap are effectively identical in function and performance.

As I see it, the differences occurred primarily as the engine bays evolved and the bean counters watched. Likely the most compelling reason for the change from the dual diaphragm Bendix disc booster the the Kelsey-Hayes one was cost and fitment. The Bendix is longer and skinnier, putting the master farther out from the firewall, getting in the way of stuff like Autopilot and charcoal canisters, hot air stove tubes and othe bits that were starting to crop up. The issue was definitely aggravated by the fact the master cylinder was now a dual res unit and longer itself. The Kelsey Hayes single diaphragm unit is much wider and shorter, making that assembly less intrusive into valuable space underhood. Add to that the bean counter's cost savings in selecting a booster that has less moving parts in it and it's a win win for the profit margin.
You've pretty much said it... There is a similar effect of multiplying pressure related to booster diameter as well as the offset sizing of the master piston vs the slave piston (caliper/WC)... after all it is fluid pressure either way. That said, I can see where a stock drum booster wouldn't provide enough assist for the discs... drums are able to be "self energizing" there is a reason why you didn't get "manual discs" with your car.
 

Ross Wooldridge

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can'tflip - thanks for confirming my understanding re hydraulics...

...and yes!, now I get the booster thing - because of dual diaphragms within the Bendix booster, the booster is effectively doubled in "size" and hence its' effectiveness or mechanical advantage is increased. That accounts for the extra length of the booster.

The single diaphragm disc booster (I.E. Kelsey Hayes) gets its' mechanical advantage by increasing the area of a single diaphragm by being wider...

Same end achieved two ways.

Cool!!
 

traintech55

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Ross, one of the things I love about our Chrysler products is the care the engineers put into our cars. They were smart enough that when they came out with something new, or upgraded an area of the vehicle they made it so easy to retrofit it into our older vehicles. On the brake systems alone you know the products were tested on the same size and weight as the older ones. So much better than Generic Motors or Ford.
 

Ross Wooldridge

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Yes - I like that too. I am not so sure the retrofit is intentional more than just good luck due to the need for Mopar (who in that era was often struggling financially) to make as few changes to componentry each successive model year to avoid high tooling and engineering costs. Ultimately a smart business practice.

Ferd and Chebbie who were often battling for 1st place had more financial gas in their tanks to engineer and develop new cars and their platforms perhaps resulting in less prior year retrofit interchangeability... just an observation that could be entirely erroneous!!

It wasn't until Lee Iaccoca came over from Ford and shook things up with/at Chrysler with the Caravan that they started to come around... and then they shot themselves in the foot anyway with financial mismanagement not too long after...

But we certainly do benefit from the good design practice with our C body cars!!
 
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