Front drum to disc master cyl. question

I am in the process of doing the front drum to disc conv. on my '71 and I am in need of some advise about the Master Cylinder. I was told that I could use the "drum" m/c that is on it now...I just need to remove the 10lb residual valve in the front resivior. My question is HOW?? I looked for a disc/drum m/c because I was just gonna replace it but I can't seem to find one with the fittings/lines coming off the right side/passenger side. Any ideas???

 

I assume that still has floor pedals and frame mounted two chamber MC? You probably need a New Master Cylinder simply because the Disc side of the system requires more volume and a larger chamber to hold that volume...........not withstanding the stroke and bore size may not be correctly sized for the front disc's.............RP4WD.com in Oregon should have the correct Master Cylinder with the right residual valve.

 

The residual pressure valve is normally in the seat area of the line connection of the MC. Start a self tapping screw in the hole and pull it out with pliers or two small pry bars. Replace with the correct one or an inline. You can use your drum/drum MC. Unlike drum brake wheel cylinders, disc pistons compensate for pad wear by continually moving out of the bore. This "consumes" brake fluid to fill the void. Just increase the frequency you check the fluid level and you will be fine. If you have any indication your MC is not 100%, follow tarry99's advice and replace it with one for disc/drum.

 

Like this
http://www.jpmagazine.com/techartic...05_drum_to_disc_brake_swap_plus/photo_17.html

 

On my flattie project I'm using a MC from a 76 AMC car, Hornet I believe. It is a manual disc/drum type that has the ports on the passenger side for mounting down on the frame. If I remember correctly I called the guys at R&P and they recommended it since I was going to disc front. You might check with them.

Mike

 

I bought a new frame mounted M/C for Disc/drum set up prior to going to booster/firewall mount. I'll check my files for the PN.

 

Found it here on the last page post #73
http://www.earlycj5.net/forums/showthread.php?26819-D27-Disc-brake-swap-on-my-71/page8

Raybestos MC36365