Brake and engine mounts questions

[Canadman]

Ok, so I'm going to do my best to both not come across like a complete moron and to provide the best description of what I'm needing an answer for. Not positive I'll be susscessful at either, but here goes...

So, I've finally been rebuilding the S2a 88 I've been delaying for the past year. The whole thing was stripped down to the bare chassis which has now been redone. Axles rebuilt, etc. At this point I'm installing new brake lines, which I've basically done. I'm converting from what was a single line brake system to a dual line system with a brake servo. So, here's my dumb question. I have my single brake line from the rear brakes running up along the top of the chassis to just past the bulkhead outrigger. I have my front brake lines running, the driver's left side along the chassis, behind the crossmember and up to the other side and meeting up with the right side (passenger) front brake line, which runs to the right wheel. All pretty simple. Here's where I'm confused. The rear brake line will meet up with its own junction, from which a line will run up along the bulkhead to the MC. And similarly, the two front brake lines will go into their own junction and a line from it will also go up to the MC. That being the case, shouldn't the rear brake line junction just have one input and one output hole? And similarly, shouldn't the front line junction have two inputs and one output? Because I can't for the life of me find a junction with just two openings. The only thing I can find is a junction with three openings, not two. So what do you do with the third opening on the rear line junction going up to the MC??

[ANDYD]

Hi, good to hear the project is moving forward.

As you are upgrading the original system I'm not totally sure what new components you are using and what your leaving out.
If it helps, here are the earlier and later braking system layouts.

Cheers, Andy

[red90]

Per Andy’s diagram, the lines all go through a PDWA which is where the front lines split to each side. It mounts on the chassis. Right side below the bulkhead. Just look at the series 3 parts catalogue.

[Canadman]

Per Andy’s diagram, the lines all go through a PDWA which is where the front lines split to each side. It mounts on the chassis. Right side below the bulkhead. Just look at the series 3 parts catalogue.

So I get that and I basically understand what the PDWA does. Here are the issues. 1. I can't find a PDWA anywhere. Anything I have found is extremely expensive and from the UK with huge shipping costs. 2. I'd rather avoid a PDWA as I've read on a bunch of other forums people who suggest they can be a pain (to bleed, can be faulty, etc) and that going instead with the more modern master cylinder with a warning light for when fluid gets low is just as good and accomplishes the same thing basically. The PDWA really only provides assistance when either the front or rear brakes (pressure) fails, is my understanding, which would similarly be picked up with a master cylinder warning light system.

This leads back to the question I asked originally which is, if I eliminate a PDWA, so now I have a 3-way junction for my front brakes (one each for the right and left and one for the MC) bolted to the chassis, for the one rear brake line, do I just connect it straight to the line (via a coupler, for instance) to the line that will go up to the MC for the rear brakes? Or do I use a 3-way junction for it as well, in which case, what do I do with the 3rd unused opening?

[ANDYD]

Can you use the 3-way junction and cap off the unused hole? If you don’t have a cap you could use a brake switch (they are cheap) that would screw into and seal off one of the 3 holes?
If making your own brake lines, put a female connector on one end to extend it to the master cylinder.

[red90]

Without a PDWA the rear line would run from the master to the axle flex line. You can include a union or two if you do not want to bend it as one piece. There is then a 3 way mounted on the axle above the diff.

[red90]

Perhaps your confusion is that you do not know there are unions? They are for joining two lines.

Here is an example. The style will depend on what type of flare and flare nuts you are using.

https://a.co/d/dZBdwoa

[Canadman]

Perhaps your confusion is that you do not know there are unions? They are for joining two lines.

Here is an example. The style will depend on what type of flare and flare nuts you are using.

https://a.co/d/dZBdwoa

No, I totally get there are unions, and I can just use one to connect the line that runs from the rear brakes and terminated down by the cross member of the chassis to a line that runs up to the MC. I guess, the point was I wanted to know if that's ok to do. Is it that simple? But it sounds like it is. Or, I can use a 3-way junction and just cap One hole off (but that seems unnecessary if I can just use a simple union.