My quest for stopping power began after I owned a '65 Mustang coupe that was just downright scary in terms of stopping power. I loved that car but coming to a stop was an event that required some planning. This prompted me to make brakes a priority on this car and I didn't want anything but the best. High quality kits are available from SSBC, Baer, Wilwood, and others. After months of reading reviews and looking at the various solutions I decided that I could build my own high quality setup for about half the price of one big name kits. Using Granada disc brakes from a bone yard is also a popular and economical choice but my conclusion was that this would not deliver the performance I was looking for. Instead I chose to use the Cobra brackets from www.mustangsteve.com which allows for the use of 1994-04 Cobra 13" rotors n front and 11.65" in back. The downside is that you have to source all the parts yourself and its not a quick and easy bolt on solution. It does require some fabrication, but its not beyond what most people are capable of. I chose to use the 2003 anniversary Mustang Cobra brakes for both the front and rear which look very sharp in powdercoat red. Mustang Steve just sells the conversion brackets so you are on your own to source the rotors, calipers, hoses, etc. He does provide a shopping list and after 30 minutes on ebaymotors I had pretty much everything sourced for reasonable prices. The only modification I made is the use of '70 spindles and hubs instead of my stock '68 setup. When I tore my car down I found that my spindles had grooving where the bearings ride which dictated new spindles. I found a good deal on a set of '70 Mustang spindles which are stronger than '68 so I went with those. It is important to note that this brake swap does NOT change the vehicle track width, but you will need at least a 17" wheel to clear the caliper. Vintage style wheels will work or with a spacer modern wheels can be used. In case you are curious, for the front and rear brakes combined I spent a total of about $1400. That price includes the brackets, rotors, calipers, and braided stainless steel brake lines for the front. It does not include a new master cylinder, or the spindles since most people will be able to reuse the existing spindle. The master cylinder will have to be replaced since the drum brake master has a residual pressure valve in it that is not compatible with discs. At the moment I am thinking to use a 2000 Mustang V6 master but have not made a final decision yet. Mustang Steve is also a VERY valuable resource and he generously donates his time to answering questions on his forum (its worth your time to check it out) www.mustangsteve.com. Unfortunately the directions that come with the kit are not very good. In my case they were meant for an old bracket he doesn't sell anymore and with no pictures it took a little trial and error to figure it out. So below I have a step by step that combines the included instructions along with some of my own information/pictures to help clarify things.
Here are the conversion brackets for the front as they arrived from www.mustangsteve.com (all bolts are included but I neglected to include them in the pic).
Step 1: Remove existing drum/hub as a unit from the spindle. Remove 4 bolts holding backing plate to spindle. Disconnect rubber brake hose from steel line and frame bracket. Remove backing plate and hose.Step 2: Place drum, open side down, in a press and place a plate across the outer bearing retainer part of the hub and press the hub out of the drum. Retain hub with studs intact. As you can see my spindle and hub needed a LOT of cleaning! Before I did anything else I scraped off the grime and then wire brushed the surface rust. A little brake cleaner and wipe down followed by rust converter paint from www.eastwood.com followed by some spray gray had everything looking great.
Step 3: With a file, remove any remaining swedged pieces from the studs. The swedges were there to retain the drum at the assembly line.
Step 4: If using plated rotors, remove any plating from the ID of the 5 holes in the rotor. This can be done with a small round file. Do not remove any rotor material. This is so the rotor can be pressed onto the studs smoothly.
Step 5: IMPORTANT: Be sure the outer diameter of the hub is smaller than the inner diameter of the rear face of the rotor (circled in red). Different rotor manufacturers use different dimensions. If this is not checked, and the hub us too large to fit flat against the back of the rotor, you will never get the rotor pressed onto the studs properly. If the hub is too large, the OD must be reduced on a lathe or using a hand grinder so it fits into the rotor. Using a grinder is OK, and there will not be balance issues if not perfectly round. (Hubs on 6 cylinder cars were actually asymmetrical, and even the V8 rotors have a big notch on one side, so balance is not an issue when that close to the center of the wheel. In my case I had to grind about 1/16" from the outer edge of the hub to make it fit inside the rotor.
Step 6: Place rotor on the hub, and use a press to push the hub studs into the rotor. This will be a very close tolerance fit. It is possible, but not advisable, to pull the rotor onto the hub using the lug nuts. This method puts undue stress on the threads and is prone to warping the rotor. Using the press, be sure all the studs are totally seated on the back side of the hub. Temporarily secure the rotor to the hub using two or three lug nuts. This will keep you from jarring the rotor loose from the studs while mounting it.
Step 7: Using (4) 3/8” fine-thread Grade 8 bolts and lock washers, mount the bracket to the spindle. The brackets are bare steel and I painted them chassis black ahead of time. The large plate mounts the to spindle face with the bolt heads on the wheel side and the nuts on the back. Use red Loctite and torque them to 45 lb/ft. Bolt the two remaining brackets (one of which is much thinner) to the back side of the first plate again using red Loctite and torque to 45 lb/ft. Bolts go into the spindle first, then into the bracket.
Step 8: Mount the hub/rotor to the spindle. Since it was already apart I also replaced the bearings and races. Using a screwdriver and hammer I worked around the back side of the race to knock them out. To install the new races I took the old races and ground the sides down so they slid back in easily. Then I put the new race in place with a plate of steel on top. I hammered the steel until it was flush with the hub but this is not fully seated. I then used the old race that had been ground down on the sides as a fixture to finish hammering and seating the race. Make SURE that the race is fully seated or the hub/rotor will not run true.Pack the new bearings with disc grease and mount the hub. Adjust bearings and check for rotor trueness.
Step 9: Install the caliper onto the front of the bracket (wheel side) using (2) 12mm x 30mm hardened steel bolts. Torque to 45 lb/ft. Blue Loctite or equivalent thread lock compound is recommended
Step 10: Connect brake hose to the caliper. Hose mounts to caliper with hose pointing up, with banjo bolt and two copper washers, one under the bolt head and one between the hose end block and caliper. The 2003 Cobra caliper requires the coarse thread banjo bolt.
The finished product with Coys C67 17x8 wheel, Mustang Steve Cobra conversion. This is not my car but it is what I hope to have when I am done.
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