which master cylinder?

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roadrr

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so ive been digging through post to no avail! i see where people ask which master cylinder for a 1970 duster 340 with front manual disk and manual rear drum and get recommedations but nothing definate on what was used, so again what master cylinder is a good replacement that people have used and works. with part numbers if possilble and where purchased please, anybody
??
 
I used one from a 1973 Dodge Dart (disc version) on my 68 barracuda with factory front disc (same as your application).

I would check Rockauto for part number reference from the various manufacturers then buy one off of eBay or Amazon.
 
The problem is that the brake part manufacturer application listings for A-body disc brakes are thoroughly screwed up. In theory, there should be two 1967-72 disc brake master cylinders: one for Manual with a 1-1/32" bore, and one for Power with a 15/16" bore (otherwise interchangeable). But you will find a lot more variations in part numbers than just those two, and some of the listed items will actually be drum brake masters. Annoyingly, most store sites don't give the bore dimension, but you can Google the part number and find a manufacturer listing that will show it (Cardone or Bendix, for example). That said, it is frequently recommended that you use the Power master cylinder for Manual disc brakes — the smaller bore reduces the pedal effort while slightly increasing the pedal travel — most people today seem to find that a reasonable trade off. I have one car with each, and I can tell you that the 15/16 bore MC feels plenty hard — the 1-1/32 bore feels like you need both feet (great for threshold braking at the track, but startling if you step into it from a modern vehicle). There are also other versions of the same basic master cylinder with other bore sizes — 1" is common on B-bodies, and 1-1/8 is also encountered. So I don't trust the application listings — I research the specs for the part shown to ensure it has the bore I want.
 
For my kelsey hayes manual front disc 10” rear drums I went with this master cylinder. So far so good been a few years now.
9D27EB60-F221-4115-95BD-91436E5A65DC.png
 
Google
MOPAR MASTER CYLINDER GUIDE BY THE RAM MAN.
These 5 pages explains it all, great if you want the correct
look that works.
Also see thread from September:
WHAT MASTER CYLINDER ?
 
This is a good thread too: upgrade master brake cylinder

To my knowledge, there are no exact rebuilt replacements available and there is no kit available (The one from Dorman is for drum/drum).

The later '73 on up style iron 15/16" bore ones will work fine however they are larger in size. The 15/16" DoctorDiff, while looking more modern, is a welcome 'no leak' style.

I recently did the DoctorDiff. Until my stock one started to go bad, it was a very hard pedal. The DoctorDiff is definitely an improvement.

upload_2020-12-22_19-46-47.png
 
An inexpensive 7/8" bore MC which works is for a 1995-99 "cloud car" (Breeze, Stratus, Cirrus) w/ ABS (2 ports). You will need a 2 to 4 bolt adapter plate ($30 ebay). I have one on my 1964 Valiant (manual), 1965 Dart (w/ Intrepid booster on Dart firewall brackets, see profile photo), and 1965 Newport (2-4 adapter to factory booster). Search for my post w/ photo showing that the pedal winds up in the same place w/ the Breeze MC on adapter plate as the factory manual MC. I have a new MC w/ reservoir on the shelf now as a spare for all 3 cars, which might have cost $25 on ebay.

I expect something from the GM or Ford racks might also work. I just grabbed something newish from the Mopar rows while at PicNPull years ago. If you go with a 2000+ MC, you run into bubble-flare fittings, which you can form with an old dbl-flare tool (youtube), but why bother.
 
This is a good thread too: upgrade master brake cylinder

To my knowledge, there are no exact rebuilt replacements available and there is no kit available (The one from Dorman is for drum/drum).

The later '73 on up style iron 15/16" bore ones will work fine however they are larger in size. The 15/16" DoctorDiff, while looking more modern, is a welcome 'no leak' style.

I recently did the DoctorDiff. Until my stock one started to go bad, it was a very hard pedal. The DoctorDiff is definitely an improvement.

View attachment 1715655422
do you have a link to the one you got from dr diff?
 
This is a good thread too: upgrade master brake cylinder

To my knowledge, there are no exact rebuilt replacements available and there is no kit available (The one from Dorman is for drum/drum).

The later '73 on up style iron 15/16" bore ones will work fine however they are larger in size. The 15/16" DoctorDiff, while looking more modern, is a welcome 'no leak' style.

I recently did the DoctorDiff. Until my stock one started to go bad, it was a very hard pedal. The DoctorDiff is definitely an improvement.

View attachment 1715655422
Disk front and drum rear?
 
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