In the Comp Prep manual, Kas Kastner recommends installing "the brake residual
pressure valve, part 116197 in the hydraulic system, before the T on the front
frame rail".
This is a single master cylinder system; the line goes from the master cylinder
to a T on the front frame rail, where the split between front and back takes
place. A line runs along the frame to the rear where it splits again for left
and right; another line runs to the front cross member where it splits again.
I have a couple of questions about this:
First, does anyone know what the specified residual pressure was? Currently,
there are two kinds available: 2psi, meant for keeping disk brake calipers from
"knocking back" too far, and 10psi, meant to compensate for overly eager drum
brake shoe return springs.
Second, why pressurize the whole system? I was thinking of installing a 10psi
unit in the line that runs along the frame to the rear brakes, to keep the
drums almost engaged; it's my belief that this is where most of the pedal
travel comes from. The front disks seem like they don't suffer from knockback.
I'd guess that 10psi is too much to apply to the entire system...
Anyone care to share experience with this sort of system?
(Also, what's a clean way to install this? The current valves all seem to have
female 1/8 NPT fittings - these *really* don't belong in a brake system, but
... use an NPT to -3 adapter and tube nuts on the line?)
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