Mustang SSBC Front Disc Brake Conversion Kit (1967-1969) Installation Instructions

Tools Required:
  • Torque wrench
  • Ratchet and Socket Set
  • Screwdriver
  • Line Wrenches
  • Wrench Set
  • Floor Jack and Jack Stands
  • Rubber Hammer
  • Bearing Grease
  • Brake Fluid
  • Brake Cleaner
Install Difficulty:
  • Moderate
  • Moderate Project
1. To start installation of the Mustang SSBC A121-2 disc brake kit, lift the car securely onto the jack stands so that front wheels are off the ground.
2. Remove the Mustang wheels from the front.
3. Remove dust cap, cotter pin, and nut from hub. Then remove the drum assembly.
4. Drain brake fluid from Mustang disc brake system. This can be done by using the bleeders, or by simply taking the line off of the wheel cylinder and the lid off of the master. Be careful not to get any on painted surfaces as it will destroy the paint.
5. Disconnect the flexible brake line from the hard line at the frame rail using line wrenches.
6. Remove the 4 bolts holding the backing plate to the spindle, and remove the backing plate assembly. I removed all of the shoes, springs and wheel cylinder prior to this, but I don’t believe that is a required step.
7. You should now be looking at a bare spindle as pictured:
Mustang Brake Conversion Kit Install Image
8. Install the caliper bracket along with the splash shield. My Mustang SSBC Brakes pictures include a brake cooling duct rather than the splash shield. Your kit only comes with the splash shield however. You should torque the bolts to 35-45 ft. lbs.
9. Pack the bearings with grease and spray the rotors with brake cleaner. Put the inner bearing in the Mustang brake rotor, and install the seal using the rubber hammer/mallet.
10. Slide the rotor onto the hub, then put the outer bearing, washer and nut on. You should spin the rotor while you torque the nut to approximately 25 ft. lbs. Then back the nut off slightly, and re-torque to approximately 15 inch lbs. Install the cotter pin to lock the nut into place.
Mustang Brake Conversion Kit Install Image
11. Install the Mustang brake pads into caliper and torque the splash shields/retainers to approximately 10 ft. lbs.
12. Check to see if adapters are needed to install the flexible line to the hard line at the frame rail. If needed, install them. Install the flexible brake lines in the caliper using the copper washer between the fitting and caliper.
13. Put the Mustang brake caliper onto the rotor, and use the mounting bolts to secure them to the bracket. Torque to 45-60 ft. lbs.
14. Spin the rotor to ensure that the rotor runs true and that it is centered within the caliper.
Mustang Brake Conversion Kit Install Image
15. Attach the flex line to the hard line at the frame rail using line wrenches and install the dust cap on the rotor using the rubber hammer.
16. Check flex line travel for any binding or rubbing by turning wheels both directions. Remember to do this again when the car is back on the ground prior to driving to ensure it is operating properly/safely.
17. Disconnect the lines and remove your old master cylinder (and booster if you have one already). Drill out the threads in the pedal assembly bracket and also drill out the dimple in the firewall.
18. Bench bleed the master cylinder.
19. Cut the pushrod hole larger using the template included so that the new booster’s boot will fit without rubbing and bolt the Mustangs brake booster and Mustangs brake master cylinder to the firewall.
20. Remove old brake pedal from the pedal assembly, and install the new Mustang power brake pedal in the upper hole. I removed my assembly as other work was being done at the same time, so see the attached picture for reference as to where the pedal now pivots.
Mustang Brake Conversion Kit Install Image
21. Connect the pushrod to the pedal.
22. Install the proportioning valve and connect lines to it and to the distribution block using the adapter fittings and lines included. You may need to bend the lines depending on where you place the proportioning valve. Be careful not to kink any lines that you bend.
23. Double check all connections, then fill the system and bleed the brakes.
24. Test the pedal to be sure you have a “hard” (not spongy) pedal, re-inspect all connections for leaking, double check that your master cylinder is full. Put the wheels back on, lower the car, check the flex lines for binding/rubbing one more time, and finally you are ready for a test drive. Go slow and make sure everything works properly with your Mustang disc brake kit before traveling at normal speeds.
25. Enjoy your new Mustang SSBC disc brake kit!