I went junkyarding today in search of a brake booster that will work on our cars, hopefully with little modification. Best thing I came up with is this unit out of a 2002 Escort. It is only 10" from firewall to end of master cylinder and it has an adjustable length pushrod. Our cars have about 11.5" of room so I think it will work pretty good. Only thing weird is it has 4 brake lines coming out of the master cylinder, Anyone got a manual to tell me what each line goes to?
Man,, what a coincidence, I was talking to a guy on the phone this morning that was doing the same thing! Dan
Keep us posted on this project. I'd like to do it on the "Green Bean" before I give it to my g'son. Looks very doable. It would be neat to get rid of that gosh awful looking shocktower support. I wish I could help you out on your question. Good work, Dennis. Jerry
That master is for a diagonal system with front disc & rear drum. The upper line (without the pressure standoff) goes to a front wheel, and the corresponding lower line goes to the opposite side rear wheel.
The front lines are already split out of the proportioning valve so that will be easy. I just need a block to tie the rear lines into one.
Maybe just plug two and use the other two? After I look at the pic again, that's what I'd do: Plug the two that come out the top and use the bottom two, one for the front, the other for the rear. Lot less clutter with only two lines instead of four...
I thought about it last night while I was supposed to be sleeping. As I said the front lines are going to be easy. If I cant find a simple manifold at the parts store, I can use the proportioning valve section that goes to the front wheels. Currently we have one line going in and two coming out. It would be easy to plumb the 2 rear lines to two of the ports and send the third to the rear. This will of course turn on the BRAKE light on the dash. I could probably loop one of the front lines through the rear section, but that may cause the pressure to be different in one side and cause it to pull when you hit the brakes. I think what I would do is just unplug the connector. The Escort master cylinder has a switch in it for low fluid. I could then splice in the light circuit into that so the Brake light in the dash would then become a "low brake fluid" warning.
I had thought about that also but I'm not sure how that would work. I'd rather use them all. Some engineer designed it with 4 outlets so I'm thinking by only using 2, the volume might not me sufficient enough for proper braking. If you were to try this, according to how I understand pbhorseman's post, the bottom 2 are on pressure standoffs. I'm not sure what that means but I'd guess it's some kind of restrictor to lower pressure to the rear to prevent lockup. If that is true, and maybe pb can elaborate, then you would want to use one of the bottom lines to the rear and one of the top lines to the front.
The pieces that screw into the lower ports of the master are there to keep the rear brakes from locking up. That car doesn't have a proportioning valve. So, ideally you would run 1 line to each wheel. If I wanted to avoid running the extra line to the rear, I would run the 2 front lines off the unrestricted ports. Then manifold the 2 restricted ports together to run the rear brakes. That should give enough fluid volume to the calipers and still keep the rears from locking up. Good luck.
