Master cylinder bore sizes

-
R

RDJ

Well-Known Member
Joined
Sep 23, 2008
Messages
281
Reaction score
6
Location
Redding, CA
I just finished my 67 Barracuda (finally!) Anyway, It has manual brakes with the 73+ front discs and 2.5"X10"rear drums. I used one of those aluminum master cylinders with the 1 1/8" bore. The brakes stop pretty good, but there is only about 1/2" of pedal travel and I have to press really hard on the pedal.

In my garage I have a brand new (not rebuilt) master cylinder (Raybestos part # MC36412 from rockauto) that is supposed to be for a 73 Dart with front disc/rear drum manual brakes. The bore size (according to rockauto.com) is 1 1/32". Would this be a better master cylinder for this system?
 
I found a 15/16ths MC at Carlisle (seller claimed it was 7/8ths) and used it in my 67 Barracuda. 73 disks up front and 11x2 1/2 drums in the back. It has a little further travel but not as much effort. I'm still working out the bugs and will probably put in the adjustable proportion valve this year. It stops but it still takes some pressure on the brakes. The rears seem to lock first, not sure though. Smaller will give you more travel, less effort and the larger will give you less travel more pedal pressure needed.
 
I changed out the MC. I like the 1 1/32" bore better. More "feel" to the pedal.
 
RDJ said:
I changed out the MC. I like the 1 1/32" bore better. More "feel" to the pedal.
Click to expand...
I'm in the same dilemma. I have a 67 Dart GT. Will be putting in a 400/ 727 next year. Installed an 8 3/4 already and plan to go with 10 x 2 1/2" Rear Brakes once I order Dr Diff Axles. I have all the front end braking stuff, 10.95" Rotors, Single Piston Calipers, etc with 75 Scamp Spindles & Adapters. Also have a Standard Disc/ Drum Proportioning Valve as well. It will be a Manual Disc/ Drum setup, but trying to figure out what Master Cylinder would work best for me. I'm thinking along the lines of at least a 1" bore (give or take) Kind of a Happy Medium between Soft Pedal or a Hard Pedal. I do want to be able to stop given we all have a lot of stupid people out there on the road these days. Anyone have a suggestion? Kinda leaning towards the Aluminum 80's type M/C's Just need to know what Model of car used a 1" bore size. So far I am leaning towards the 15/16" from mid 80's Diplomats, 5th Ave. (As suggested by Cass (Dr. Diff) But I am cheap (actually just a poor dude) lol and need a Part number so I can order it from Lordco. I am in Canada. And have no access to the US market.
 
You must log in or register to reply here.
-

Back
Top