Single resevoir to double res Master Cylinder

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wheelz 63 dart gt

wheelz 63 dart gt

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I bought a 1968 Master Cyl. for my 63 Dart. I am not sure which proportioning valve/distribution block I should buy. Mine only has 4 ports. I need one with another outlet to add the new brake line. Im having a hard time finding one locally at Napa. Does any one recommend a specific part. I bought the M/Cfrom Rock Auto, good deal too. They Dont have proportioning valves though, and the junk yard here in SoCal does not have cars with front drums. Thanks for the help.:prayer:
 
grimreaper said:
If you you this type you can adjust for your car. If you make any changes you can adjust again.....

http://www.summitracing.com/parts/SUM-G3905/
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There are only 2 ports on that one. The one i need should have one port for the rear inlet, two ports for the front inlet, one out to the front resevoir, and one out to the rear resevoir. Right? The one on there has 3 inlets and one out let for the single resevoir. I have a double res now so i need one more outlet and a new brake line. Right? Im not sure though. I need help . Thanks. What should I buy, and where should I install it? Its really just a 3 in 2 out distribution block. 9/16 and 1/2 on the m/c
 
I might have a spare one from a 68-69 dart--(i'll check) if not--- block the rear port on your current distribution block(goes to the rear), then connect directly to the rear of the m/c & you will be good to go. Lawrence
 
If you are staying drum-drum, you don't require a proportioning valve. The car was already designed for the right front-rear split by the size of the wheel cylinders and shoes. If you decide to add one (good idea if you plan to later switch to front disks), you can get inexpensive ones with a hand knob (1 port in, 1 port out) to place in-line with the rear brake tube. I paid ~$20 on ebay for a chrome plated one (no-name, probably Chinese).

Re plumbing, if same as my 65 Dart, you currently have a single "distribution block" which is 1 tube in at top and 3 tubes out. Just a "4-port Tee", no internal parts. Unscrew the rear tube (rear brakes) and put a "3/16 inverted flare coupler" on the end of the tube. Plumb from there to the MC "rear" port, which is (usually) the forward fitting (small reservoir). Install a "3/16 inverted flare plug (male)" in the rear port of the Tee to seal (not used).

Your current tube from the MC to the Tee is probably 1/4". If the new MC has a 3/16 tube port, best is probably to put a "1/4 male inverted flare to 3/16 female inverted flare fitting". I found one in the bubble packs at Autozone. You can then run a new 3/16 tube from the MC "front port", which is (usually) the aft port (large reservoir). An alternate is to discard your factory Tee and install a 3-port Tee with the port sizes you need, but must strap it to the frame.

I got some of the fittings above at an industrial supply, but I think most retail auto parts have them if you search. Finally, some "gotchas" on brake fittings. There are different size "tube nuts" for the same size tubing. Manufacturers use these to "key" the brake lines so one can't hook them up wrong. Your existing 1/4" tube might screw into a MC port, but might not seal if that port is for a 3/16" tube (w/ big nut). Always look at the internal inverted flare in the fitting. Another thing to watch is that newer cars tend to use the European "bubble flare". I got an MC from an Intrepid and a Breeze, both late 90's. Both MC's looked similar but the Intrepid's had bubble flare ports. You can use your existing double flare tool to make bubble flares, but use the "flat side" of the bar. Several You Tube videos on that. The tube sizes are the same.
 
ok , I bought a 1963 m/c rebuild kit because I needed a new push rod to hook to my break pedal. I took the new plunger out of my new double resevoir M/C because the new pushrod would not fit . I bench bled the M/C and it seemed to work fine. Will this work? I called ,and looked every where and could not find a new push rod for my 1968 M/C. The new m/c is obviously longer than the old one, and I would think it will just need more fluid to work. They are both 1 inch diameter and it fits nice. I still need one more 1/4 to 1/2 brake fitting to hook my rear line straight to the master cylinder. I will hope I did this right. Thanks for the help
 
Based on junkyard parts I have, it appears that when Mopar went to dual reservoir master cylinders both front and rear tubes are 3/16"D. They put a bigger tube nut on one of them so you can only correct them one way at the MC. If so, don't screw your original 1/4"D tube into the larger fitting. While the nut may fit, it will seal properly only on a 3/16" tube. Always look at the inside of the fitting.

If both MC's have the same diameter, it shouldn't take any more fluid (and pedal travel) when you apply the brakes. The volume flow is determined by the size of the wheel cylinders, how far the shoes must move before they contact the drums, and hydraulic compressibility from the rubber hoses, any air bubbles, and the fluid itself.

Not sure what "1/4 to 1/2 brake fitting" means. They are usually named by the size of the tubing (3/16 or 1/4), though nut size also vary. As I said, make sure you know what tubing size each port on your MC is for, don't go by the size of the nut.
 
Hey Bill, what I meant was brake line adapters. The first resevoir port is 9/16, and the second resevoir port is 1/2.My brake lines were different and would not directly fit. I am just hoping my 63 m/c plunger, and push rod will fit in my 68 m/c. I still need to bleed my lines, but it seems ok so far.
 
wheelz 63 dart gt said:
Hey Bill, what I meant was brake line adapters. The first resevoir port is 9/16, and the second resevoir port is 1/2.My brake lines were different and would not directly fit. I am just hoping my 63 m/c plunger, and push rod will fit in my 68 m/c. I still need to bleed my lines, but it seems ok so far.
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Did the push rod work for you?
 
When i changed out my engine this spring I did the change over then. hardest part was finding the correct fittings at the local parts store. Much easier to remove distributing valve and working with it on the bench also.
 
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