[zooky08]

Hey guys does any one know how to hook up a proportioning valve for rear disc conversion
Car is a Sierra nt, so it has the two hardlines going to the rear.
It didnt come with any kind of instructions

Cheers

[zooky08]

Any one?

[want33s]

You will need to fit it near the master cylinder rear brake output.
You'll probably need a new line made from master to proportion valve and from valve to the flexi line below master.

[zooky08]

Well I have a flaring tool so I'll just buy some fittings

[missmyljdaze]

what type of flaring tool are you talking about- its been years since I messed about with brake lines, but I am pretty sure your average flaring tool (plumbing) gives different flare angles to those needed for brake lines.

Last time I just had the lines professionally made- and was surprised at how cheap they were (4 x custom made race spec. stainless braided lines for $35 in 1990)
In my opinion, its not worth the hassle- or risk- of making your own.

[zooky08]

It's a flaring tool for brake lines
I need them made from hardlines, not the flexy brake lines

[missmyljdaze]

onya mate- as long as you have the right tools, materials and the knowhow, go for it.

when you usually have to make do with vice grips, fencing wire and liberal amounts of devcon like I do- you learn there are the occaisional limitations to what you can do.....

for the record- a mechanic I used to know showed me the results of wrongly flared brake lines on the remains of what had once been a lovely fiat 124 coupe.

[zooky08]

Just had a look at my master cylinder and both lines from the master cylinders go to the rear
The front brakes are just fed of the rear lines?

[steak_knife]

zooky08 wrote:

Just had a look at my master cylinder and both lines from the master cylinders go to the rear
The front brakes are just fed of the rear lines?

look harder..........

[christover1]

I'd be getting advice from brake specialists, too important to get wrong.
Later models have a funny 3/3 split system,
meaning still have 3 brakes working,
if part of system springs a leak.
You can't put prop valve on either line,
or won't work right. IMHO
My Vitara has a prop valve,
stock, it is after the 2 line, and is on the single to the rear brakes.

On my old sierra I used better brake pads up front,
cheap nasty on rear, that worked for mine.

[steak_knife]

christover1 wrote:

I'd be getting advice from brake specialists, too important to get wrong.
Later models have a funny 3/3 split system,
meaning still have 3 brakes working,
if part of system springs a leak.
You can't put prop valve on either line,
or won't work right. IMHO
My Vitara has a prop valve,
stock, it is after the 2 line, and is on the single to the rear brakes.

On my old sierra I used better brake pads up front,
cheap nasty on rear, that worked for mine.

Work's well.......
But I can still lock the rear at will.....

[zooky08]

I don't know how it works but I see the front lines coming of the side of both lines from brake master cylinder
RHF and LHR matched
LHF and RHR matched

[steak_knife]

Can't fit one then.....

[zooky08]

Well then that's shut isn't
I'll just have to hunt down some bigger piston calipers

[missmyljdaze]

Zooky- I would be taking Christo's advice and asking a brake specialist or even your department of transport- even the mechanical engineers at the RAC or whatever you have in your state for some advice before you go any further- advice is cheap, brake failure isnt.

the wrong mods to your brakes could even void any insurance cover if you have to claim after an accident.

[zooky08]

I won't be touching any of the brake lines any more.
I'll be just screwing the line into a new caliper that has a big piston for the front

[puddlejumper]

Ive fitted rear discs to my NT SJ413 (1985 i think) I fitted a Willwood adjustable proportioning valve. Works well and is 100% street legal - Here in NZ anyway . Heres a few pics that may help.




Mine has only the one hard line to the rear of the vehicle.

[zooky08]

puddlejumper wrote:

Mine has only the one hard line to the rear of the vehicle.

then yours is completly different setup to mine
So I still cant fit the valve coz there's no separate rear line coming from the master cylinder.

[want33s]

Just fit WT brake lines...

[zooky08]

So wt has two lines going to the rear to a valve which splits down to one line right?
So could I just replace the block below the master cylinder with wt and still run the two lines to the rear, but on the block there is a separate rear brake line going to the master cylinder?

I don't really want to pull all the line out after I've just put every thing back together and replace the hole lot with wt brake line set up.

Also can't I just run lwb vitara calipers up front?

[skyman]

Check out zuwharrie.com.

They show how to re route the lines on that distribution block below the master cylinder so you have two lines going front, and two going rear.

Right now, you have master cylinder that has one line for front, and one line for rear. Then those two lines go to the alloy block and get switched around.

So that one line form the master feeds the right front, and left rear, and the other line from the master feed left front, and right rear.

They call it cross braking. This way say.. the right rear springs a leak, then left rear, and right front will still work. and can stop the vehicle safely.

If it was one line from the master for front, and one for rear, then when you spring a leak in the right rear you would loose both rear brakes, and same for the front. See if you only have front, or rear brakes and need an emergency stop, the ass end will try to come around on you. That;s really bad for a SWB vehicle.

So what you need to do to fit a proportioning valve is re-route the lines on that alloy block so you have one line from master feeding both front, and one line from master feeding both rear.

Then put the proportiioning valve on the one line fom the master that feeds both rear brakes..

I hope that doesn't get too hard to follow, and it helps some. Feel free to PM me with any questions.

AS always be very very very cautious with the brakes (yeah I know they already said it, but I had to, too.)

[zooky08]

Yes that's very clear to understand
By just changing the block to wt will let me hook up a poportioning valve
On a wt it has two lines going to the rear from block that goes into valve at the rear withs converts to one line to a t piece On diff
I'll keep the stock two line going to the rear and just change the nt block to wt nd change the master cylinder lines to accommodate the poportioning valve
This is my understanding any way
When done I'll test the breaks on my property(dirt,blacktop)
Give it a good work out then take it to a brake place to double check

Also do you have to get rear disc engineered at all?