Front drum to disk conversion - Part 1

 Getting ready with parts.

The next main job to be done on the Mustang is to replace the front non power assisted drum brakes with power assisted disk brakes. While the drums work fine, disk will be better. The drums certainly give the leg mussels and workout.

I initially decided to source a full kit from the US. The kits are made up of new master cylinder, booster, callipers, disks and adapters to mount the callipers on the existing drum spindles. 

Well, that was the plan. Upon investigation, I could get a kit from Griffs in Ballarat, however, the booster was going to be anodised and not the correct type for a 71-73 Mustang. The price for the kit was around $1600. I checked other suppliers that could sell me a kit with the correct booster, however the price for those kits were above $2100. As my main reason for purchasing the kit was to get the near correct booster, I decided that I should investigate just getting a correct booster and master cylinder from Custom Mustangs and just purchase parts from local wreckers for new spindles and callipers.

I found that I could get a new near correct booster and master cylinder cheaper than buying booster from a wrecker and have it rebuilt and then buy a new master cylinder. So I ordered the master cylinder / booster from Custom Mustangs in Carrum.

Here is an original booster and master cylinder.

Here is the kit from Custom Mustangs. It is not exactly the same but not far off.

I then checked with wreckers and found that I could buy a new pair of spindles and alloy Girlock callipers from an 1986 / 1987 XF Falcon that are single piston and simple design. These would cost around $350. I could also source spindles and callipers from an XC / XD Falcon that are a cast metal design for about $250. In talking to the local brake shop expert he suggested that the alloy XF callipers would be better as they are more reliable.

Upon searching Facebook marketplace, I found a set of XF callipers and spindles for $150 in Melton. So I jumped into the Mustang and went for a spin to Melton.

The guy had just removed them from a XF Falcon and came with the upper and lower control arms with springs and disks still assembled. I advised I did not want / need the upper and lower arms, so we removed the upper arms from the set up on site and I returned home with the rest of the parts to continue disassembly at home.

After a quick pressure wash, I disassembled the parts and binned all the bits I did not need. 

The disks were in good condition all be it a bit rusty but with in tolerance. Unfortunately, Ford changed to a larger 70.8mm front hub design in around 1976, so the disks had 70.8mm hubs and the wheels I have on the car have 60mm hub holes, so I can not use the disks that came with the parts.

Once disassembled, I set about removing the old brake fluid from the callipers and removing the pistons. I used compressed air to gently push the pistons from the callipers.

Here are a bunch of pictures showing the front spindle and callipers both together and separated.

My good make Russell also has a Mustang and he also has a sand blaster, so the next step is to go and sand blast the parts to clean them up. Then go to the local brake parts shop to source new front disks, bearing and calliper rebuild kits, plus new tie rod ends as the size of the bolt is slightly different.

I will then rebuild the front ends while not in the car so as to make the install simpler. (Hopefully!).