In the previous issue, we detailed the installation of a front disc brake kit that was used to convert a formerly four-wheel drum-brake equipped 1968 Camaro to a set of front discs that boasted six-piston calipers and drilled, slotted and vented rotors with aluminum hubs, all of which could be concealed behind 15-inch rally wheels (“Big Brakes for Stock Wheels,” HMM #136).
The system used in that story is made by Wilwood Engineering, and it offered an interesting and effective alternative to factory-style front discs for enthusiasts who want to retain stock-type wheels. That set-up could be used in conjunction with rear drums, offering a significant improvement in braking over the standard front drums, but we, like the owner of the ’68 Camaro that served as the subject of that story, couldn’t help thinking that the new front discs ought to be working in conjunction with a corresponding set of rear discs.
Rear disc brakes were fairly exotic in the 1960s, found on some European sports models, but very few American cars outside of the Corvette. One of the only other models to offer such a set up was the 1969 Camaro, with the now-infamous JL8 option that brought a set of brakes based very closely on the Corvette’s, though only about 200 cars were so equipped. Rear discs wouldn’t return to an F-body until the 1979 Firebird Formula and Trans Am with the optional WS6 package.
The brakes from a WS6 Firebird can be swapped to the earlier models, as can the rear discs from some later GM models, and taking either route can provide a solid upgrade to go with factory front discs, but to round out the six-piston front brakes on this particular ’68 Camaro, we looked back to the source.
Wilwood offers a number of rear brake options, but the Dynapro Low Profile Pro-Series Rear Parking Brake Kit is the perfect mate for the Dynapro system installed up front. This kit uses four-piston aluminum calipers that mount to bracket assemblies that also contain a separate drum-type parking brake.
The rings are placed over the axle’s hub with the smaller-diameter side facing out to engage the rotor.
The parking brake uses the rotor’s hub as a drum in an arrangement similar to many late-model factory rear disc systems. It’s an effective and reliable setup that alleviates the need to incorporate a parking-brake mechanism into the calipers. The kit used here was designed specifically for the 12-bolt Chevrolet rear axle, and in this case, a brand-new example was being installed, sourced from Moser Engineering. The new axle assembly’s specifications were based on the original Chevrolet design, including the housing ends and C-clip-type axle shafts, so the Wilwood kit intended for an original 12-bolt bolted up without issue.
The new rotor slides into place on the axle shaft. Wilwood intends for the use of 1/2-inch wheel studs, and recommends upgrading stock axles from the 7/16-inch studs found on many GM cars of the period. Our new Moser axles came with the larger studs already installed. Remember that the parking-brake drum is in the rotor’s ”hat,” so the shoes may make contact when the rotor is being installed.
We returned to Premier Restorations in Sloatsburg, New York, and again followed along as Josh Montes De Oca performed the installation. Once again, the 15-inch rally wheels bolted up to conceal the new brakes, retaining the stock look but with substantially improved stopping power.
Sources:
Premier Restorations
845-712-5566 • www.premierrestony.com
Moser Engineering
260-726-6689 • www.moserengineering.com
Wilwood Engineering
805-388-1188 • www.wilwood.com
Though the Wilwood kit has a new parking brake mechanism, the cables to join it with the vehicle must be purchased separately. Here, too, Wilwood can provide cable kits separately, though not designed specifically for every application. The team at Premier ordered the universal Internal Parking Brake kit, which has the required Ford-style cable ends to connect to the calipers.
Wilwood’s parking brake cable kit includes a bracket to mount the two cables coming from each brake assembly together, positioned here along the lower edge of the transmission tunnel, directing the cable ends toward the Camaro’s factory parking-brake connection.
Included in the cable kit is a pinch block to fasten the cable ends, which is threaded onto a clevis, intended to connect to a parking-brake lever assembly.
However, for the Camaro, Josh takes the pinch block, retaps its threads, and then attaches it to the factory parking-brake stud, merging the Wilwood assembly with the original parking-brake pedal and retaining adjustability.
Once the brakes were bled and the parking brake was adjusted, both were tested. The master cylinder must be appropriate for the system; Wilwood can provide technical input to guide installers with this. This car used a GMstyle master cylinder and an adjustable proportioning valve, which required some road testing to determine proper front/rear bias. When completed, the Camaro’s braking capability was vastly improved over the stock four-wheel drums, but with its rally wheels on, no one would suspect a thing.
