So you’ve got your big shiny wheels with fancy sticky
rubber that looks great from a distance. Move closer and the bling from the
wheels is diminished because of that crusty drum brake poking out. Sure you can
wire brush 40+ years of crud from the drum and paint it but nothing looks better
and shows you mean business than 4 wheel disc brakes. Not only are rear disc
brakes a visual improvement, they also perform better than drums.
In this article we’ll detail how to install our
11.65” Rear Disc Brake System Conversion onto a 66 Mustang.
Read on to see how simple this install is:
The first steps of the install are to get the car in the air and the wheels
off. We’d recommend jacking and using stands on the frame rails so the rear end
hangs lower. This will give you more clearance between the axle and rear frame
Remove the brake fluid hard line from the back of the drum. These can sometimes
be stuck fast so go careful not to round off the soft fitting. Use a flare
wrench if it won’t budge.
The axle hard
lines need to be modified later so we went ahead and removed them completely.
So fluid didn’t drip from the ‘T’ fitting we plugged them with some spare tube
nuts that we welded closed the hole.
Next you’ll need to remove the outer drum to gain access to the parking brake
cable connection and backing plate retaining bolts. Remove the parking brake
cables. Rotate the axle around and use the hole in the axle flange to remove
the 4 retaining bolts.
We used a die grinder with a cleaning pad to clean the crud from the end flange.
Now we can start the installation of the new parts. First up, the billet
aluminum end flange bracket. This bracket features a series of holes so you can
‘clock’ the caliper position up or down to clear leaf springs etc. We found
that the 10 o’clock position passenger side and 2 o’clock driver’s side worked
best for us. This bracket is retained using the original backing plate ‘T’
bolts and nuts and features an integral bearing retaining design. You can
choose to remove the bearing and remove or cut off the stock retaining plate, or
leave the bearing on and bolt the stock retainer on over the new bracket. We
chose the easy route and bolted it on over the new bracket.
To center the caliper on the rotor, we have to measure the axle standoff. To do
this we measured using dial calipers from the front face of the axle flange to
the backside of the newly installed bracket. We include a handy shim chart in
with the instructions to aid in shim stack selection.
Ours measured 2.485” on the passenger side and 2.5” driver’s side and the chart
told us to use a .100” shim. We inserted the shim between the end flange
bracket and the intermediate bracket both sides of the car, put a dap of red
Loctite on the bolt threads and installed the intermediate bracket.
To ensure the rotor is hub centric the kit includes a centering shim. Slide
this onto the axle.
This kit features the upgraded slotted, drilled and zinc washed rotors. Slide
the rotor onto the studs and to help hold it in place we loosely installed a lug
nut onto one of the studs.
Next we installed the appropriate caliper making sure the bleed screw was up. A
dab of blue Loctite on the threads and torqued to 85ft-lbs helps keep the bolts
The kit includes custom built parking brake cables. To start the install of
these we hook the correct end into the caliper and secure it with the supplied
Using the factory parking brake cable clamps we route the cable along the
underside of the car and click the ‘finger’ clamp on the other end of the cable
into the factory bracket in the transmission tunnel.
Next we loosen the adjusting nut on the parking brake equalizer rod and overlap
the new and old cable by 12”. We cut the old cable and secured the new and old
cable together using the supplied cable clamps. Once the other side is
installed we tightened the adjusting nut on the parking brake equalizer rod and
tested the parking brake.
Now we move back to the rear end and install the supplied stainless steel
braided brake flex hoses. Start by measuring from the axle end flange 12”
toward the center section, using the supplied hose clamp; secure the hose
mounting bracket to the axle tube. You could also choose to weld the bracket to
your housing instead of using the clamp.
Secure the hose into the bracket with the brake line clip.
Attach the other end of the hose with the banjo bolt being sure to ‘sandwich’
the hose banjo fitting with the new crush washers.
Using our old hard line we trimmed off the section that used to run to the drum
backing plate, double flared it and connected it to the new fitting on the flex
Once the hoses and
hard lines are installed both sides, we checked for interference. It is
critical to ensure adequate clearance from bump stops, exhaust and shocks. If
we encountered any interference we’d have to loosen the banjo bolt and/or hose
mounting brackets and move the hose before driving.
After a thorough brake bleeding and wiping the front/rear rotors down with brake
cleaner to remove any greasy fingerprints, it was time for a test drive! The
parking brake works way better than it ever did with drums and the rotor looks
great behind a set of 17x8 American Racing Torq Thrust M wheels!