Good evening All,
This is my Quantum H4i, a kit car based on a 1994 mark 3.5 Ford Fiesta XR2i 1.6 Si.
It's been off the road on a sORN for two years plus near a tidal river. So, I'm sorting
out the consequences of disuse and sailty air..
Among the tasks concerned is a brake rebuild. I've nox refurbished the back brakes and
am now working on the fronts.The extended pedal travel has now gone now the self adjusters
work. The other issue was a distinct lack of 'bite' from the brakes and I now know why. It was
insanely hard to get the pistons out of the calipers. The main seals were rock hard and practically welded to
the pistons and there was some rust in the seals' grooves. This leads me to believe that such braking that I had
was largely coming from the back brakes. Also, the front discs turned out to be deeply pitted. So, everything is now pristine
and I have new discs, pistons, seals and braided hoses to fit.

Now, here's where I need a little help. I want to upgrade the system by fitting the master cylinder and servo from a Mark 5 XR3i.

This is what's on at present...


Yep, standard XR2i. On the right, note the pressure reducing valves
in the lines going to the rear brakes.

Here's the new master...



I've grit blasted this and it's ready to be rebuilt using the new seals and pistons in the kit
I've bought.

So far so good but here's the question. This is a Mk.5 XR3i setup in situ.



As shown, there are two sizes or tube nut. On the right is a pair of what I suspect to be pressure reducing valves
for the rear brakes but it isn't clear how the brake lines run.

This pic should make things clearer still...



The question, then, is which two connections are for the rear brakes? I intend to put the Fiesta
reducers in line. So can anyone help?

Incidentally, I know that I have to shorten the pushrod on the Escort servo. I have the kit to do this
by welding or cutting threads and I assume it's a matter of making at match the length of the Fiesta
pushrod.

Thank you for reading, I wait in hope!!

 

Well, the plot thickens, kind of.

I've downloaded an Escort Haynes manual and found out a little bit more.



This little diagram suggests that the valves in the pic of the
Escort donor's brake master setup up are indeed pressure valves,
presumably to stop the rear brakes locking up when used in anger.

I also disovered that the donor is clearly non-ABS. If it was, there'd be
bundy pipes going back to the reservoir.

The snag is, my picture doesn't clearly show which of the four pipes
on the master go to the back. I've searched for a schematic even
this is apparently in the rocking horse teeth category, or something!

These things are sent to try us...