manual front drum to KH disc swap

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rrvolare

rrvolare

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what p/n master cyl did you guys use .. and where did you get it from ...
 
I was told to use original 4 wheel drum manual brake master ???
 
rrvolare said:
I was told to use original 4 wheel drum manual brake master ???
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You will want a new master. Go to the parts store and ask for a master for disc brakes, they may ask power or not get power (in 67 they used the same one on both power and non power, I doubt 69 is any different).

There is a good chance they will have it in stock.

Alan
 
I was told to use original 4 wheel drum manual brake master ???
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I was told the same thing. The problem is that the disc brake master will have a larger reservoir for the front brakes. The drum master doesn't have that extra capacity. As the pads wear, you would have to check the fluid very often so you wouldn't run it low. Getting a disc brake master is the best choice.
 
using one of the newer mopar aluminum master cylinders from Doctor Diff comes with the 2 bolt to 4 bolt adapter...working great....
 
RAYBESTOS Part # MC36406 More Info {Professional Grade; Bore Size=15/16" Number of Ports=2 Primary Outlet Size=9/16x20 Secondary Outlet Size=1/2x20}
Front Disc Brakes; Rear Drum Brakes;

If you don't have power brakes,, the 15/16 bore will be easier on your leg, and will give you better "feel"..
 
I've got a newer aluminum master that came out of my old 82 Cordoba. It looks exactly like the one Dr Diff sells. I might just buy the adapter and run it.
 
Remanufactured
Power Brakes
Front Disc Brakes
Rear Drum Brakes
With Reservoir
Cardone 10-1326

Remanufactured
Manual Brakes
Front Disc Brakes
Rear Drum Brakes
With Reservoir
Cardone 10-1326M
 
i wouldn't go any larger than 1" piston in the master.
some of the power units were 1 1/8". you don't want one of those.
 
What you will usually end up with is a drum brake m/c (equal size resevoirs) with no residual valve in the rear outlet (feeds the front brakes). It will work fine, but itsbetter to get an m/c with the larger rear resevoir if you can find one. That way as the pads wear, there's always plenty of fluid. Also if you're road racing there's less chance of boiling. Minor issue otherwise.
 
This is a quote from 340sFastback in my build thread, and is what I did. Mine are manual brakes. They work great.

"I recommend a 15/16" master cylinder for reduced leg effort. Order one for a '73 340 Duster with power disc brakes. It will bolt right in to a manual brake car. 7/8" rear wheel cylinders help to balance the brake system too along with a proportioning valve."
 
If you get the 2-4 bolt adapter plate, you have many options for aluminum MC. I recently bought another adapter for $35 on ebay. I use an MC from a 95-99 Breeze w/ ABS on my 3 60's Mopars, but most people here use a 90's Dodge truck MC. I like my 7/8"D and don't have much pedal travel (even w/ silicone fluid), but 15/16" D should be fine.

When power MC bores do differ from the manual one (not in early A's) they are usually SMALLER. That sounds backwards, but not after you consider the lever ratio in the stand-off brackets.
 
I am thinking i will order the POWER disc brake master cylinder for 67-69 dart with front disc and rear drum .... reason being that i kept the original distribution block and added in the rear hold off valve that came factory on some darts with this setup brakes ... ANY info appreciated on my suggestion and combination .... AGAIN thanks for all the help!
 
Does anyone know if, when using the correct adapter and using the aluminum master, you need to lengthen the brake pushrod? I've never noticed the pushrod being adjustable...
 
rrvolare said:
I am thinking i will order the POWER disc brake master cylinder for 67-69 dart with front disc and rear drum .... reason being that i kept the original distribution block and added in the rear hold off valve that came factory on some darts with this setup brakes ... ANY info appreciated on my suggestion and combination .... AGAIN thanks for all the help!
Click to expand...

Take a look at Chrysler's Master Technicians Conference pamphlets over at www.Imperialclub.org The will give you a lot of the factory info and explanations right from the horses mouth.
 
rrvolare said:
I am thinking i will order the POWER disc brake master cylinder for 67-69 dart with front disc and rear drum .... reason being that i kept the original distribution block and added in the rear hold off valve that came factory on some darts with this setup brakes ... ANY info appreciated on my suggestion and combination .... AGAIN thanks for all the help!
Click to expand...
I think the "rear hold-off valve" you refer to is actually a "proportioning valve". It was used in the earliest front disk cars (~67-68?, not sure about 64-66). Later, it was incorporated in the distribution/warning/hold-off block, which was then termed a "combination valve". Usually a new adjustable proportioning valve is simpler, cheaper, and better, but you are already plumbed so use that.

One thing to look for is if a power MC will lock the manual push-rod's rubber bushing. I don't know if manual MC's have a groove for that in the piston. Probably doesn't matter since I recall that some years use the same PN for power & manual MC's.

There have been questions/complaints about where the pedal sits for various manual setups. Some think the accelerator and brake pedals should be at the same base height, but others say not. Some have cut and welded manual rods to shorten. The 2-4 adapter makers say they put the MC piston at the correct location when using a newer 2-bolt MC. Of course, adjust your brake switch to match wherever your brake pedal ends up sitting.
 
OK if this hold off valve was used in early 67 and possibly 68 model year vehicles with kelsey hayes front discs and rear drums .. does anybody have a photo of ORIGINAL master cylinder used with this setup ?
Thanks !
 
One thing to look for is if a power MC will lock the manual push-rod's rubber bushing.
Click to expand...

I had to use an adjustable pushrod on my Cordoba. The rod locked into the stock aluminum master.
 
You guys may already know this .... BUT there is a gentleman ... very knowledgeable also ... he is repopping a body rotors in 4 and 4.5 patterns for KH systems ... I tried after market hubless rotors from Murrays... autozone etc... and the fit like SHI** hitting calipers .... etc...
he informed me that my disc upgrade is correct ... distribution block with rear PROPORTIONING inline block ... not called hold off valve ..... PLUS he informed me to upgrade to a 5/16 bore master cyl... which i think i received from ROCK AUTO ... SO closer to finalizing the upgrade ..... NEXT moving to ther rear brakes to freshen up ...
 
rrvolare said:
You guys may already know this .... BUT there is a gentleman ... very knowledgeable also ... he is repopping a body rotors in 4 and 4.5 patterns for KH systems ... I tried after market hubless rotors from Murrays... autozone etc... and the fit like SHI** hitting calipers .... etc...
he informed me that my disc upgrade is correct ... distribution block with rear PROPORTIONING inline block ... not called hold off valve ..... PLUS he informed me to upgrade to a 5/16 bore master cyl... which i think i received from ROCK AUTO ... SO closer to finalizing the upgrade ..... NEXT moving to ther rear brakes to freshen up ...
Click to expand...

5/16 bore master cylinder?
You must be talking about The Ram Man. Sorry but from all I have heard I am not that impressed.
 
rrvolare said:
... he is repopping a body rotors in 4 and 4.5 patterns for KH systems ...
Click to expand...

Hi,

As I'm planing a KH disc install, can you please tell me who the vendor is that is repopping '66-72 A-bdy rotors? Especially interested since also available in 4.5" pattern.

Thnx, Mike in FL
 
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