SSBC W123-3A, Installation Instructions Manual, Page: 5 / 9

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W123-A, -3A Revision 3
6) To insure the proper function of your SSBC brake system several other parts will be required to
complete the installation. If you did not purchase these parts at the same time as your brake kit
they can be ordered from SSBC or your distributor. If you choose to source your own parts
please keep the following points in mind.
a)
Master Cylinder
A master cylinder designed for disc brake applications must be used. Be sure the depth
of the piston is correct for the pushrod length you are using. For manual brake
applications a bore size of 15/16”-1” is needed. For power applications a 1” bore size will
work correctly.
b) Power Booster
The vehicle must have a minimum of 16” of vacuum at idle for the booster to work
properly. If you do not have at least 16”Hg you will need a vacuum pump or you will have
to run a non power system. Be sure to select a booster for your specific year, make, and
model with the proper brackets and pushrod. For some vehicles you will have a choice of
the outside diameter of the booster. Generally speaking a larger outside diameter will
provide more boost than a smaller one. The only exceptions are double diaphragm
boosters. Keep in mind that your space for a booster will be limited by things like big
block engines and tall valve covers. SSBC generally recommends a 7”-9” diameter
booster for your vehicle.
c) Proportioning Valve
Installation of a proportioning valve will be necessary to insure the rear brakes do not
lock up prematurely causing a loss of control. This is necessary due to the increased
pressure generated by the disc brake master cylinder. SSBC recommends an adjustable
proportioning valve to allow fine tuning of the proper rear brake pressure for your specific
vehicle.
d) Brake Line Connection
All brake lines should be steel or stainless steel tubing. All flares should be SAE Inverted
double flares. For some applications little or no plumbing changes will be necessary
while others will require all new lines from the frame rail up to the master cylinder. Be
sure all lines take smooth bends avoiding kinks or restrictions in the lines. Be sure to
connect the brakes to the proper reservoir of the master cylinder. For GM cars the
reservoir closest to the firewall usually feeds the rear brakes, while on most Ford and
Mopar vehicles that reservoir feeds the front brakes. If you are using an aftermarket
master cylinder check with the manufacturer for proper connections.
7) Brake fluid and bleeding the system
a)
After completing all hydraulic connections, install new brake fluid (at master cylinder
reservoir). Remove the master cylinder and bench bleed the master cylinder. Pump
brake pedal several times to initially fill the system and advance the caliper pistons to
their working position.
WHEN BLEEDING THE SYSTEM, PUMP FLUID SLOWLY INTO THE NEW
SYSTEM. IF FLUID “FOAMS”, IT WILL TAKE A LOT OF FLUID TO BLEED THE
BRAKES. SOFT PEDAL IS A RESULT OF POOR BLEEDING. TAKE YOUR TIME!
8) Bleeding the system
a)
When pressure bleeding is employed the correct pressure setting is 10-15 psi. (max.)
for the bleeder tank.