Front disc brakes were perhaps the best value per dollar on the option list when Ford cars were ordered new. Available at a small additional cost, they were a big improvement over the standard drum brakes.
Most of a car's stopping power comes from the front brakes. The factory option only upgraded the front axle, but this was considerably helpful. However, the best setup for modernizing our classic Ford braking system is a disc brake at each wheel. Although a little more expensive, it's worth the money.
Brakes are mechanisms to convert kinetic energy into heat energy. When brake heat is generated faster than it's dissipated, saturation occurs. While an enclosed drum has little way to ventilate heat, the rotor in a disc-brake arrangement is out in the slipstream and is often cast to allow ventilation through the interior of the rotor.
When water is present inside a drum brake, it acts as a lubricant and makes stopping difficult. In addition, often only the drum on one side of the car gets wet--such as when it's driven through a puddle. The result is a nasty pull at the steering wheel when you hit the brake pedal. With disc brakes, water is thrown off the rotor when the pads come in contact with the rotor surface. Disc brakes shed heat and water more readily than drum brakes.
So, the next question is how to install four-wheel disc brakes on an early Mustang or other special-interest Ford. One good answer is a Master Power disc-brake kit for both the front and rear axles. Our '73 Mach 1 Mustang had manual front disc brakes from the factory, but they were in need of a complete rebuild. We want to tackle the whole car at once, adding rear disc brakes while completely refurbishing the front brakes.
Here's the new Master Power...
Here's the new Master Power front disc-brake kit. It includes new single-piston floating calipers with metallic pads. The American-made rotors are 11-inches in diameter and cross-ventilated for excellent heat dissipation. New seals, bearings, and hoses are also included, and all kits include a new master cylinder. With a Master Power kit, there's no hunting for this or that: Everything needed is included except brake fluid. For the complete power-brake setup (PN DB1528PNS), which includes a new vacuum booster, the cost is $849. For the manual-brake kit (PN DB1528MNS), the cost is $695.
This photo shows the Master...
This photo shows the Master Power rear disc-brake kit. It also includes new single-piston floating calipers equipped with metallic pads. The rotors for the rear axle are ventilated, which is nice, as the rear rotors are often solid on other kits. All mounting brackets for the conversion are included, as well as new brake lines and parking-brake cables. The rear disc-brake kit (PN DB1515R) has a list price of $695. Both the front and rear kits require a minimum of 15-inches wheel diameter.
It's obvious the car has been...
It's obvious the car has been sitting for a while as the rotor and caliper are rusted over. Some WD-40 was required to get the caliper mounting bolts loose and remove the old caliper.
The rotors aren't any better...
The rotors aren't any better looking than the calipers on this job. It's a good thing the Master Power kit includes new fasteners, bearings, and hoses: We're going to need all of it. Everything except the spindle is headed for the scrap heap.
The spindles on the car are...
The spindles on the car are cleaned and the new wheel bearings are packed with fresh grease. After a new inner bearing is dropped into the rotor, the grease seals can be installed.
After the rotor has been prepared...
After the rotor has been prepared with a seal, grease, and a bearing, it can be installed onto the spindle. Lubricate the edge of the seal with a little grease, and rotate the rotor as you install it to help the seal past the shoulder at the base of the spindle.
Here we install the outer...
Here we install the outer bearing into the rotor. Next are the washer, castle nut, and cotter pin. Torque the nut to 15 lb-ft, and then back it off to the nearest slot to install the pin.
With the rotor spinning freely...
With the rotor spinning freely on the spindle, the caliper can be installed. Once the pads are in place inside the caliper, collapse the piston enough to create adequate clearance for the rotor.
Once the calipers are installed,...
Once the calipers are installed, the new brake-line connections can be completed. New retaining clips for the lines are included in the kit.
Remove the drums on both sides...
Remove the drums on both sides of the rear axle. Getting the old drums off can be a wrestling match. If so, find the adjustment port on the backing plate, remove the plug, and loosen the tension on the brake shoes to remove the drum.
Next, disassemble and remove...
Next, disassemble and remove the drum-brake mechanism, including the return springs and shoes. Don't breathe the dust from inside the drum assembly; a simple, paper respirator mask from a home supply store is enough protection.
With the brake shoes out of...
With the brake shoes out of the way, the backing-plate fasteners can be accessed and removed.
With the four fasteners removed,...
With the four fasteners removed, the whole axle assembly can be pulled from the axle housing. The object is to remove the drum-brake backing plate.
Before proceeding, a steel...
Before proceeding, a steel spacer is installed over the axle to compensate for the thickness lost when the old backing plate was removed.
The axle goes back into the...
The axle goes back into the axle housing with the spacer in place. Here, new fasteners are used on the assembly, which now incorporates the primary caliper-mounting bracket.
New cap screws are inserted...
New cap screws are inserted into the primary caliper-mounting bracket, and each is then fitted with a spacer sleeve. These sleeves will locate the secondary caliper-mounting bracket the correct distance inward.
The secondary caliper-mounting...
The secondary caliper-mounting bracket is placed in position. All fasteners in the kit are retained with nylon locking nuts, making them impervious to loosening due to vibration.
With all of the caliper-mounting...
With all of the caliper-mounting hardware installed, it is a simple matter to install the new rotor onto the axle flange.
Here the Master Power rear...
Here the Master Power rear caliper is placed on the new brackets. It's a perfect fit. The floating aspect of the caliper design means the caliper moves to compensate for pad wear.
On the backside of the rotor,...
On the backside of the rotor, we see the brake lines being attached at the caliper. If the copper washers are not in place on either side of the hose fitting, there will be a leak. The other end of the new lines attach at the hard lines on the axle.
Here's the completed rear...
Here's the completed rear disc-brake installation. Next, the new master cylinder was installed, and the whole system was flushed and bled free of any air. We're confident this new four-wheel disc-brake setup from Master Power will give our Cleveland-powered Mustang the whoa to match its go.