How To Install Cobra Brakes On A Vintage Mustang

Install a new retainer gasket, then slide the axle back into the rearend housing.

At the rear, the Vintage Venom kit is designed to fit 8- or 9-inch small-bearing axles. After removing the existing brakes, pull the axle to prepare it for the Vintage Venom conversion. You'll need to press-off the axle bearing, then install the Vintage Venom bracket between the axle retainer and the new bearing. To make sure the axle retainer can move closer to the end of the axle, grind down the casting lines on the axle and enlarge the retainer opening before assembling the retainer and bracket.

The OE axleshafts can be reused. As with the fronts, the lug holes were opened up and longer ARP studs pressed in.

The aluminum spacer is next. Note that the rear spacers are narrower than the front spacers. They are clearly identified as front and rear.

Due to clearance issues on the narrower '65-'66 cars, the rear calipers and rotors must be installed as an assembly. As you slide the rotor over the studs, place the caliper in position before pushing the rotor all the way on. Secure the caliper with two bolts.

One of the items purchased from Ford, per the Vintage Venom instructions, were a pair of moan brackets, which were designed to reduce brake noise on SVT Cobras. Vintage Venom suggests using these brackets, which mount to the axle with a U-bolt and to the aluminum bracket. However, on the shorter '65-'66 rearend, the bracket is a tight fit, requiring some trimming to mount between the bracket and the rearend U-bolt. Merv elected not to use the brackets on his GT. If noise is a problem, he can install them later.

Rear brake line fabrication starts with the trimming of the bracket on the Cobra rear hose. The Vintage Venom instructions supply the measurements.

To convert to power brakes, remove the existing master cylinder. Merv's '66 was still using the single reservoir master as found on '65-'66 Mustangs. The new Tran-Am Racing power conversion unit will give him the added safety of a dual reservoir master cylinder.

Bolting the hose to the caliper, with the hose running toward the front of the car, provides some indication of what type of rear brake line fabrication is needed. On '67-and-later cars, it may be possible to bend the existing brake lines if they are long enough. On '65-'66 Mustangs, swapping the '67-and-later lines may work, or you may have to fabricate entirely from the junction block on the rearend to each hose.

Aided by the fact that the heads were off the engine, the Trans-Am Racing power booster/master cylinder assembly slid right into place. However, in our case, there was interference with the metal tab on the shock tower, which is used for the factory strut tower to shock brace. Merv tried the Trans-Am Racing assembly on a '66 parts car and it fit perfectly; that's just another indication of how early Mustangs can differ structurally. Since the GT has an export brace, Matt trimmed the tab for clearance.

Although not an afternoon bolt-on, the final results-both in braking performance and in appearance with the modern wheels-are definitely worth the effort.

Here's the installed power booster. The Trans-Am Racing setup utilizes an aluminum spacer plate (thinner for automatics, thicker for manual transmission cars) to adapt the booster to the firewall. It's still a tight fit between the firewall and shock tower. Brake lines must be fabricated for both the new master cylinder location and dual reservoirs.

The emergency brake cables are a combination of the early Mustang's original front cables and late-model Mustang rear cables, so they must be joined at the middle. Some modification to the cables is required, as explained in the Vintage Venom instructions. Cable routing and modification also varies between model years.