Drum brakes have a bad reputation, and they’re usually the first things to hit the swap meet pile. Early C2 Corvettes were only available with drum brakes, but they worked adequately, thanks to larger drums and a lightweight car compared to other vehicles of the era. Our project car, a ’64 Corvette coupe, has relied on manual drum brakes for its whole life, but as we continue to upgrade the car we realized that adequate just isn’t enough for this modified Vette. Just because it stops doesn’t mean that it’s up to the task of dealing with today’s highway speeds, and more importantly, dealing with the incompetent drivers that share the road with our precious vehicle. Even if you’re not planning to go racing, a brake system designed to withstand the abuse of racing is a great upgrade for an early C2.
Swapping to disc brakes on an early C2 is an easy process, but you do have a few choices to make. One option is to run stock-style disc brakes from a later-model C2. And while this may be more affordable than a full aftermarket kit, you’re looking at a change in the car’s track width. This change can be exaggerated even more (up to 1 1/4-inch per side) with other aftermarket kits that use a more universal, non-Corvette specific rotor. This wider track can be problematic if your car is lowered or if you’re already pushing the limits of tire and wheel fitment with your current combination. The goal with our car is to retain the vintage-style 15-inch wheels we currently have so we wanted a kit that would allow proper fitment, while also keeping the wheels tucked in nicely.
What we found was a Wilwood Forged Dynalite Pro Series disc brake kit. With 11-inch rotors and four-piston calipers, the kit works with 15-inch wheels and only increases the track width by 1/4-inch per side. The kit also bolts onto the original drum brake spindle, which helps with overall cost and installation time. We were sold on the Wilwood kit immediately, and it only got better as we dove into the project. The kit featured clear and detailed instructions, and included all of the necessary hardware to assemble the new disc brake system.
We spent two evenings in the shop, using regular hands tools to complete the job. In addition to the disc brake kit, we used a Wilwood brake line kit to connect the hard lines to the calipers. After bolting the components into place, we bled the brakes, and installed the wheels. On the first test drive it is important to properly bed the brakes. Wilwood suggests beginning with a series of light decelerations to gradually build heat in the brakes. After several cycles of light stops, we increased the firmness of the stops, continuing to build heat. Finally, we did 8-10 decelerations from 55 mph to 25 mph. Wilwood also suggests avoiding sitting stopped with the brake pedal depressed while the brakes are heated from the bedding process.
We are pleased with the performance of the kit, and the appearance of the drilled and slotted rotors and powdercoated calipers exceeds any of the factory-style disc brake conversions on the market. This was a drama-free disc brake install that didn’t affect our tire and wheel fitment choices. We kept our 15s and we now have big braking power thanks to Wilwood’s implementation of racing technology on street-friendly kits. Our early C2 is now ready for safer highway usage, and those disc brakes will also come in handy on backroad adventures, whether they are the straight or twisty variety.
1. Our ’64 Corvette project car still featured the original drum brakes. We started by removing the dust cap, the cotter pin and then the retaining nut.
2. Behind the retaining nut is a flat washer with a keyway made into it, and behind that is the outer wheel bearing. We carefully slide the drum and hub assembly off of the spindle.
3. Our car’s drum brakes functioned properly, and all of the parts were in great shape. We could’ve continued using this system but we wanted more braking power for our modified Corvette.
4. After we removed the springs, shoes and other brake hardware, we can remove the large bolt that holds the wheel cylinder in place. This bolt also fastens the backing plate to the spindle.
5. Two additional bolts are undone in order to remove the backing plate. Keep in mind that these are pass-through bolts with nuts on the backside. The bolts also pass through the steering knuckle arm.
6. Before we remove the backing place and wheel cylinder, we remove the flex hoses. It’s never a good idea to reuse brake hoses, but the Wilwood kit requires new hoses due to a different fitting size on the caliper.
7. With the backing plate removed, now is a good time to use some brake cleaner and a wire brush to clean the spindle. After a thorough scrubbing, we masked off the area the wheel bearings make contact with and gave the spindle a fresh coat of paint.
8. Since we intend on keeping our 15-inch wheels, we went with a Wilwood Forged Dynalite Pro Series front brake kit (PN 140-12458-D). It features 11-inch rotors, which are drilled and slotted for maximum cooling. The four-piston calipers will provide plenty of clamping power.
9. The Wilwood kit comes with a two-piece caliper bracket, and that is the first part to be assembled on the car. Finger-tighten the bolts holding the two pieces together until final assembly. Mock-up is first to make sure the brackets are aligned properly.
10. Included in the kit is the proper hardware, including spacers and shims to align the bracket. All cars require the wide spacer, but some may require one or more of the 0.015-inch shims, as seen here. We only needed one shim.
11. Wilwood suggests using Loctite 271 red thread locker on all hardware in the kit. The caliper bracket’s upper bolt gets torqued to 140 ft-lb.
12. Two new bolts and nuts are supplied for the bottom caliper bracket bolts. These bolts pass through the spindle and through the steering knuckle arm. The lower bolts are tightened to 40 ft-lb.
13. Next is the aluminum hub assembly, which is a crucial part of the lightweight Wilwood disc brake kit. The first step is threading in the new 1/2-20 wheel studs into place. Keep in mind that the hub features two bolt patterns, so be sure to use the pattern that matches your wheels. For us, it was the 4 3/4-inch pattern.
14. The inner wheel bearing is next. We’ve always had good luck using the old-school “palm” method of packing the bearings with grease. Simply put a blob of grease in your palm and roll the bearing in it, while also packing it in the gap between the bearing race and the cage.
15. With the inner wheel bearing in place, we install the supplied grease seal. It may take some persuasion, but be sure to use great care with a rubber mallet. The seal must be flush with the backside of the hub assembly.
16. The Wilwood SRP brake rotors are directional, due to the angle of the cooling vents and slots, so it’s important to orient them properly. The flush side of the rotor mounts against the rotor adapter. The rotors feature Wilwood’s Black Electro Coat finish.
17. Once we’ve designated the left rotor from the right, we can attach the rotor to the aluminum rotor adapter supplied with the kit. Wilwood also supplies the hardware, and suggests applying Loctite 271 to the threads before tightening them to 25 ft-lb.
18. Next, we attach the rotor and adapter to the hub assembly, making sure that the rotor adapter is pushing the rotor away from the wheel mounting flange. These also get the Loctite treatment and we tightened them to 45 ft-lb.
19. Using the palm method, we pack the outer wheel bearings. The grease is standard “disc brake grease” available at all parts stores. It’s cheap and it will take you years to go through a tub of it.
20. The hub and rotor assembly is ready to slide onto the spindle. We weighed the drums versus the disc brake setup. The complete drum assembly weighed 32 pounds per side and the Wilwood disc brakes weigh in at 15 pounds per side.
21. The kit comes with a new keyed washer for the outer wheel bearing. It slides into place and then we install our original spindle nut, tightening it until there is no slack.
22. If the hole doesn’t line up for the cotter pin, you can tighten the nut a little more without running the risk of wheel bearing damage. Then, install a new cotter pin.
23. The Wilwood dust cap screws into the hub and features an O-ring to help keep it in place and keep grease from seeping out.
24. We mocked-up the supplied bolts and used the supplied 0.035-inch shims to center the caliper on the rotor. Wilwood’s instructions suggested starting with three shims, but extras are provided if needed for your application.
25. We apply Loctite 271 to the threads of the two caliper mounting bolts and torque them to 40 ft-lb.
26. The kit comes with Wilwood BP-10 brake pads, which slide into place after the caliper is mounted. After the pads are in place, we installed the large cotter pin, supplied in the kit.
27. The brake flex lines were not included in the kit, but Wilwood does offer a brake line kit (PN 220-7699) that fits properly. We attach the flex line to the hard line, and then install a new retaining clip.
28. The other end of the flex line attaches to the caliper, using a supplied 90-degree fitting.
29. We can bleed the brakes, starting with the passenger-side rear brake, and working our way toward the brake that is closest to the master cylinder. The Wilwood calipers have four bleeder screws. Use only the upper bleeder screws, first bleeding the outboard screw, and then the inboard screw until the air is out of the system.
30. We slide our 15x4.5 Rocket Strike wheels (with Coker Firestone 5.60-15 tires) over the studs for the first time. Keep in mind that the Wilwood kit uses 1/2-inch studs, so you’ll have to get new lug nuts if you were using the original 7/16-inch studs and lug nuts. We got ours from Coker Tire.
31. We did our homework to ensure proper fitment before we ordered the brakes, but it feels good to see proper clearances with our vintage-style wheels. Improved braking power, less weight and great looks are perfect reasons to ditch your drums.
Photography by Tommy Lee Byrd