I am working on plumbing the brakes on my project. 1952 Chevy car chassis, 1952 stock front brakes, and an S10 rear end with stock drum brakes. I used a 10-1329 master cylinder per a write up I found here on the HAMB to get a dual chamber setup. So this leaves a couple of questions.... Specs on the MC: Primary Port Thread Size: 9/16-18 Inch Secondary Port Thread Size: 1/2-20 Inch The S10 rear end has 1/4" Female IFF fitting: The stock brakes up front have 3/16" line. I know I will need adapters to go from the MC ports to the respective brake line sizes. Does it matter which port goes to front or back? Is it wise to use 3/16" lines to the rear end and then adapt the 3/16" line to the 1/4" line or is this a nono? Or should I go 1/4" line from the MC all the way to the rear? Thanks for any input/advise!
Thanks Dick. From what I can find, this MC was used on a lot of late 60's-early 70's Chevrolet cars & trucks, It looks like both chambers are the same size. The only real difference I can tell are the port sizes. My thoughts were that if I needed to go with a 1/4" line to the S10 rear, maybe use the 9/16"x18 port as the physical size of the port is a bit bigger? It just so happens that the 9/16" port is on the front of the MC. I'm just not wanting to create a braking problem....
Many drum/drum masters have what appear to be equal sized fluid reservoirs (like your 10-1329) but may not be 50/50 in fluid displacement, so it's important to know the original application for correct front to rear plumbing, because most/all front drum brakes on cars/light trucks have larger wheel cylinders that require more fluid volume than the smaller rears. There is no "rule" on dual master plumbing, drum or disc, in spite of what you may read. The port sizes are different so the lines cannot be switched during vehicle assembly or service.
I would use 3/16 line for everything. The rubber hose with the T fitting for the rear can be changed to a 3/16" one. On the Master they often used the larger and different sizes on the outlets so the would not get switched around- I remember buying the fittings and cutting the brake line and taking the original fitting off and re-flaring it. I remember also going to the junkyard and getting some, cut the line and unscrew them, clean them up and nice and cheap.
Point taken Bob. I believe that convinces me to go front/front rear/rear. Now the question that remains is the line size to the rear and I can get to work!