I am going to use an S14 MC (15/16) to run the brakes on the Datto. (running R33 GTS-T Calipers on the front and R31's on the rear)

The question is, How the hell do you plumb it up? They seem to have an extra barb sticking out where ABS goes? Not 100% sure what it's for and was hoping someone would tell me!

I have attached a photo of an S13 MC, and a Tokico S14 replacement part (cause I couldn't find an image on the net and I haven't got my camera on me!)

Cheers

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

Well,

Been doing some thinking/reading, but I am still unsure.
I think (someone please confirm this) the S14 master cylinder has two lines for the front brakes and one for the rear.

Can someone confirm this, or recommend someone that can?

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

Ok....
(Damn I hate answering my own questions....)
For all of you who are following at home:

Two lines are for front calipers so if one fails, the other one is still operational. One line goes to the rear. The one that goes to the rear has a pressure restriction built in.

Anyone seen an ABS S14 unit? (might be tempted to hook some ABS goodness up... )

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

so an s14 master bolts straight on to the booster? would be the same for a sunny booster right?
and skyline 1 inch master would also have the same bolt pattern?

2 for front one for rear
But both fronts are drilled together and if one fails so too does the other

One to the rear
No pressure restriction though
The valve on the side has 4 orings in it and a shuttle...... it doesn't really propotion

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1969 Datsun 1000 wagon (Daily)
1969 Datsun 1000 coupe (Next project)
1969 Datsun 1000 coupe (Long term project)
1974 L34 Torana replica (In the build)
1976 SS Torana hatchback (Restoration project)
1976 Cadillac sedan deville (Pimp cruiser)

I'm not entirely sure. All I know is that bolt spacing on the Stanza MC that I have is different to 200B, and 120Y. Hope that helps.
I think it's the same as R32, although you'd have to ask...
It doesn't bolt straight on... You have to modify the booster slightly (remove two of the four pegs that stick out), and slot the holes in the MC to suit.

Dattoman1000,
So then why do they but the 'restrictor' or what ever you wanna call it, on the rear brake then?

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

I guess that depends on your definition of failure.
If the RH side (for example) has a restriction, then it means the LH side will still operate fine. If the RH springs a leak, the LH side will still operate, but at a reduced pressure, (proportional to the leak volume).
With some MC's, they use a ball valve or shuttle so that if there is a pressure imbalance, between LH and RH side, such as a leak, the shuttle will constrict the volume going to the leaking side, and 'bias' it to the side which is working. I think this is how the 'restrictor' works for the rears. Basically the piston area for the rears isn't as much as the piston area for the fronts. Somehow, there must be a 'bias' or proportioning that means the fronts get more fluid flow.

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

theres no biasing or restricting, there a 2 piston inside the M/C and then both lines will go to a seperater which will then send the fluid to the LHF and RHR and also then to RHF and LHR using seperate lines that way if u get a leak in one calliper or piston the brakes will still work just very crap cos u r only using half of the cars brakes. its all for safety. those to lines from the M/C on a s14 would go to an abs unit which would then distribute the fluid as i said before.

This MC didn't have ABS hooked up.
It has two lines to the front, and one single one with a restrictor in the rear.

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

Here's my S14 MC mounted up to a Stanza Booster.
There's a bit of stuffing around involved.

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1972 Datsun 1600, S14 SR20DET Engineered (204rwkW @ 17psi.)
viewtopic.php?t=6579
#SR20Datsun @SR20Datsun

Why are you chosing the s14 MC? What benefit does it offer besides being 15/16th?
I am just trying to understand its choice over others. I am using a 1" datsun MC. It is damn heavy but my brother uses the same on his zed which has big nissan four spots on the front and Xf brakes on the rear. More than enough according too him. Actually too much really.

what did you get the 1 inch master out of?
i know you can get up to 15/16th in the alloy datsun ones, out of a 280zx
but im looking for a 1 inch ones, but will most likely go for a r32 or 300zx one as ive got 300zx brakes all round

Mate

I am drawing a blank but I was sure it was from a 280zx. I will ask my brother what it was. It is one of the only steel MCs I have seen. IE HEAVY.

i thought that the turbs 280zx was an inch....but brake master cylinder book says different

i would think patrol or something being cast iron, 4x4 thing of not caring if they weigh a tonne

using the Stanza booster you can use the same basic deign master cylinder.
from 13/16 up to 1 inch
various nissans from mid 80s inc GTR
in most cases using up to GTR front & rear calipers not much need to go over 15/16
my experience

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