I’ve received a couple of questions about the Wilwood brakes I used at the rear of my S2. Here a few photos of my solution to adding disk brakes and some thoughts about why I did what I did.
My first requirement was that my solution should use the existing brake lines and hand brakes cables. In searching for rotors I discovered that the offset of the 2009 Ford Focus rotors would allow me to have a simple brake mounting plate. No offsets, not angles and no welding required. However, since the Ford wheel bolt pattern is 4x4.25” I had to drill four new bolt holes on my chosen 4x100 wheel stud pattern.
The mounting plate is somewhat heavier then optimal, but just fine for my proof of concept installation. It’s just a ½” thick 6061 aluminum plate cut to shape and then an ~1/8” relief was cut into the plate where it mounts to the trailing arm to center the calipers over the 0.35” thick disks. The caliper mounting holes were located per the drawings for the Wilwood caliper from their site. I choose to use their two piston Dynalite Pro caliper as the brake calculations seems to indicate that even with four small pistons per caliper it would provide excessive braking at the rear. This caliper did require a different fitting on the brake line vs the stock Europa drum brakes.
The parking brake is also a Wilwood unit. After I made my first mockup, I discovered that there was no easy way to remove the disk with the parking brake caliper in position. I added mounting ears to the ½” mounting plate to locate the parking brake. I also built a small, metal plate that is located by the Dynalite caliper mounting bolts. To this little plate I added a thicker piece to locate and secure the parking brake cable.
Of course mounting the Dynalite calipers at the top requires that the calipers be removed and held vertical when bleeding the brakes. At some point in the future I’ll likely build another set of mounting plates with the Dynalite calipers mounting vertically at the rear.
You can also see in the photos the non-stock axles I’m using. Originally I had the hubs machined to match the stock Europa rims and back plates for the stock drum brakes. However, with the new Ford Focus rotors I made a sleeve that I pressed onto the hub that located the center of the rotors as well as the center of the VTO Classic-8 wheels that I am using.