Brake line fitting size

[Shadow]

Are the brake line fittings on our cars metric or standard?

[supercrackerbox]

Standard

[Shadow]

Cool, that's what I thought. 3/8 24......right?

[Shadow]

Anyone?

I'm ordering every last thing I can think of right now! Just want to be sure.

[135sohc]

Do you have a service manual ? In the brake section there is a line diagram drawing of the brake system and what size fittings are used at every connection. I'd look in mine and tell you but I dont want to give you the wrong information since my books dont cover 85's.

[Shadow]

Cool, I'll check the manual. I'm 99% sure it's going to be 3/8 24, but just want to be 100%.

[Mike M]

I just went through the process of doing a adj prop valve, and keep in mind, depending on what you are doing.. there are two of the lines at the prop valve that have a larger size nut (7/16) as opposed to the normal 3/8 everywhere else.

[Shadow]

Ya, I just noticed that tonight when I took it apart. I'll be changing one of those ends (prob just replace the whole line) as the Wilwood adj prop valve uses All 3/8 24 fittings and only 1 line to supply the rear.

[RoadWarrior222]

Oh there might be a gotcha at the master cylinder or distribution block, being a metric fitting at that end... or a larger fitting than normal on that size line or something. Don't remember clearly, but needed an adapter of some kind when I used a pre-made bend to fit line.

[minigts]

3/8" seems big for a brake line. When you do the one line to the rear, where are you going to split it or how do you intend to split it? I thought about doing that as well whenever I get around to that part of my build. I also thought about putting in a control valve that would be accessible from inside the car. Like a proportioning valve just under the driver's seat. There is a plug I think close to the left side between the door and the seat.

[22mopar]

they are refering to wrench size (3/8") not line size which is 3/16"

[minigts]

haha Just saw the thread title next to your answer. :$ Eh, sometimes I just don't pay attention.

[Shadow]

When you do the one line to the rear, where are you going to split it or how do you intend to split it?

I ordered a nice brass tee that has a mounting hole. I'm going to put it where my two line come together in the rear.

[22mopar]

you don't want to run just one line to the rear. this will affect the braking system. see the stock system is a diagonal braking system. if you have a failure you'll still have 50% of your braking. when you start manipulating the system, you're opening yourself up for some serious potential problems.

[RoadWarrior222]

Well that's the theory, I've seen it work in practice on European cars, their master cylinder reservoirs are bulkheaded much higher up, some fill separately each side. Ours still seem to spit too much fluid out of the top of the good side into the bad side, so you get practically no braking effort in the good side. I like to think of this as the "Titanic" version of dual circuit braking. (If you'll remember the "sinkproof" bulkheads in the Titanic didn't go all the way to the top of the hull such that water could overflow each one by one.)

[Shadow]

My adjustable prop valve only has 1 outlet for the rear. + the hydro handbrake I'm running requires you to use 1 line in order for it to work properly.

[22mopar]

you can do what ever you what but if you don't really understand the physics and engineering of the brake system, it would be best if you leave it alone before you kill yourself or someone else. I don't see the abilities to out engineer the people that designed the system to begin with.

[Shadow]

you can do what ever you what but if you don't really understand the physics and engineering of the brake system, it would be best if you leave it alone before you kill yourself or someone else. I don't see the abilities to out engineer the people that designed the system to begin with.

No offence, and I understand your concern, but I do understand the physics and it IS possible to install a Better than stock system in this day and age. My braking system will be better than it ever was..........