Disc Brake Swap.

As a Cougar owner, unless you are lucky enough to pick up a car optioned with the disc brake package, you have probably given serious thought to the drum to disc swap. I’ve driven both and managed to cope with the drum system but the simple fact is that disc brakes are going to stop your car better and more reliably. I don’t know about anyone else but when you weigh the $500-$1000 cost of the upgrade against the safety of yourself and others it’s not such a hard decision to make.

So what is entailed in a drum to disc conversion? Well the fact is you are going to need to get a little dirty. The key to the whole swap is your front spindles. The drum spindles must come out and be replaced with disc spindles. This will mean the partial disassembly of your front suspension. Make a note here folks. If you aren’t sure you can handle this job then get it done by a professional. You are dealing with the steering, suspension and braking system for your vehicle and if any one of those things fail due to improper re-installation the results could be both catastrophic and deadly.

For the purposes of this article we will be dealing with the braking system on our current project car, a 1967 Cougar XR7. This was a fairly low optioned car which included four wheel drum braking. Our current disc upgrade is only going to deal with the front brakes. I know that down the road we will be swapping out the rear end in this car so for now we just want the comfort and reliability of front disc braking.

There are some places out there that offer kit’s to do the drum to disc conversion. Not having used any of these kit’s myself I can’t endorse them in any way but you can dig up some comments from people who have by doing a quick Internet search using Google. The website ”discbrakeswap.com” has various kit’s for the “Granada” disc upgrade but again you are going to want to research his kits on your own to find out what kind of results they get and what kind of quality it is. For those of you that are doing a more sincere “restoration” and have an eye for correct part numbers and so forth, you might want to give the good folks at West Coast Classic Cougars a call or John’s Classic Cougars and see what kind of recycled parts are available. I can’t stress enough when dealing with Cougar’s it’s always best to go to the people that know Cougars for your solutions whenever possible to avoid parts confusion.

If you do choose to use parts you recover from another vehicle you want to be very particular about where you get your spindles. Here is a breakdown of spindle setups from the mid 60s Mustang and Cougars:

-         1965 to 1966 mustang spindles were all interchangeable.

-         1967 to 1969 drum spindles looked the same as 65-66 spindles but use a different geometry for the steering arm that uses a larger tie rod hole.

-         1967 disc spindles have the same geometry as the 67-69 drum spindles.

-         1968 to 1969 disc spindles also utilized the slightly larger tie rod connector.

-         1970 to 1973 disc spindles utilized the same steering geometry as the 67-69 spindles but incorporated a significantly beefier spindle with larger bearings and larger tie rod ends.

In our case, a friend of mine managed to pounce on an old 71 Mustang in a wrecking yard and relieve it of it’s front braking system. This worked out great for our disc brake upgrade project because the 70-73 model year spindles are the strongest “stock” spindles that were produced for these cars. Just as an FYI, some of the performance cars in 1969 also used the beefier spindles (like the BOSS cars and the 429 cars) but the 70-73 spindles are your best bet. I won’t swear to this but I am pretty certain that your 14 inch wheels wont work on the beefier spindles due to hub clearance and caliper clearance issues as well. Keep in mind that you want to grab the strut rods and old calipers from your donor car if that is the route you choose to go. The calipers will save you about $40 each in core charges and the strut rods will be used to replace the articulated struts in the 67 cars.

So after much blood sweat and tears, and a couple cans of WD-40 we got the old brake assemblies apart. Depending on the condition of your rotors you can either have them turned or, worst case scenario, get them replaced. Make sure you order the rotors for the correct year of spindles you have and not for the year of your car. In our case the rotors look great but we will have them turned before mounting them on the 67. We turned in the old Calipers for a set of new single pistons at the local auto parts store and prepped up for the big changeover. Because we will be using 71 spindles on a 1967 suspension we also needed to get the 71 tie rod ends to get everything to play nice. While gathering parts we also purchased an adjustable proportioning valve, new master cylinder, set of brake pads and new bushings for the strut rods. You will most likely also want to redo your front brake line so if you don’t have a flange tool and a good 8 to 10 feet of brake line you might want to pick that up as well.

I am not sure what other people’s cars are like as far as a “clean” undercarriage but our project 67 car is definitely showing her age. It is best to prep for the disassembly by cleaning the steering and lower suspension connectors thoroughly and then dousing them  with WD-40 several times over the couple of days prior to doing the disassembly. We got the car up on some jackstands and went to work on the front suspension. After getting the sway bar and strut rods out of the way, loosen off the tie rods and ball joints. This can be a real chore so be prepared to put in some good muscle and a few bloodied knuckles. While working on the suspension you are going to want to have a jack under the lower control arm to keep a little bit of compression on the springs. Once you have both the tie rod and ball joints loosened up you remove disconnect them starting with the tie rods, then do the balljoints. At this point you should be able to work the spindle out of the wheel well. Make sure that you’ve disconnected all hoses and lines.

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