image 1 - the fitting on the rear of a '56 carburetor where the vacuum source is obtained to connect to the check valve on the vacuum diaphragm of the booster,
image 2 - diagram of the original brake line plumbing with a power brake booster.
image 3 - diagram of the power brake booster plumbing with a Dual Bowl master cylinder. The larger half of the master cyl is plumbed to the booster and front wheels.
The smaller MC bowl is connected to the rear wheel cyls.
image 4 - a stock power brake booster mounted to the fender-well in a '55. (before cleaning & painting)
The large black rubber hose from the check valve on the booster diaphragm connects to the vacuum source on a '56 carburetor, or intake manifold vacuum if you have a different carb & intake manif setup.
FYI, if it's helpful, partway down the page at this link is an
Install Directions button that opens a disc brake installation / instructions document.
https://www.classictbird.com/Front-D...ductinfo/DISC/
If your disc brake kit did not come with some replacement rear brake hardware to balance them with the new front Discs a Combination / Proportioning Valve is most likely needed and the plumbing will be different to accommodate it. Contact vendor that supplied the disc brake kit you have.
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