Newton's first law of motion states that an object in motion stays in motion, unless acted upon by an outside force. What does that mean for car building? Sure, gravity and wind will eventually slow a car down, but you need to build the braking system equally, or more impressively, than the acceleration system. This is often overlooked when trying to make your car fast-you truly don't know the importance of good brakes until you don't have them.
One fast lap at any road course will show you exactly how brakes fail. Coming up on the first turn after the straightaway, you'll brake hard to make the turn. The next couple braking zones may go smoothly, but once those brakes start to get hot, the pedal will get soft, and the brakes will eventually fail. This is called brake fade. On the street and at the dragstrip, fade is less of an issue, because the brakes aren't being applied repeatedly. One pass every hour at the track won't heat your brakes enough to show fade. Street driving shouldn't use enough brake to exhibit that problem either. Our project Street Fighter Mustang, on the other hand, will need to have exceptional brakes to survive what we will be putting it though.
For the most part, bigger is better when it comes to braking systems. The greater the rotor diameter, the more leverage the caliper has on it, and the more heat it can dissipate. The downside to oversized rotors is that it adds unsprung and rotational weight-the most important weight to keep off. Luckily, many aftermarket brake setups use aluminum hubs and adapters, so the overall weight may be the same or less than the stock assembly.
This month, our '66 Mustang-Project Street Fighter-is getting a much-needed brake upgrade. The '66 was equipped from the factory with a single-master cylinder, manual four-wheel drum brake setup. Let's just say the force necessary on the pedal to slow the car at a normal stoplight was enough to equal a workout at the gym. Since we plan on tracking the car, we needed a more substantial set of brakes. We turned to Wilwood for direction. We knew we would be running Vintage Wheel Work's V60 17-inch wheels, so 13-inch rotors and six-piston calipers could be used with ample clearance. The single-reservoir master cylinder wouldn't be compatible with the new brakes, so we used their bolt-in 1-inch bore, dual-reservoir master cylinder. Along with the brakes, we are replacing the factory spindle with Total Control Products' direct replacement spindle that uses the '70-73 Mustang's larger bearing. The Wilwood kit is designed for this specific spindle as a bolt-on installation.
We encountered some hurdles, and gained some knowledge through this installation, one thing being that six-cylinder Mustangs don't have the same steering components as the eight-cylinder models. With every project there are mistakes that will be made; that's why we're here to make them for you.
Bleeding the brakes is the last and most important step to ensure your brakes' performance. Modern brakes use hydraulic fluid to transfer the force applied from the brake pedal to the brake pad. The reason this works is that the fluid doesn't compress. When changing a line or draining the fluid, air enters the system. Unlike the fluid, air does compress, so if it's left in the lines, you'll get a soft, spongy brake pedal. The process for bleeding is simple. Starting with the wheel farthest from the master cylinder, slip a tube over the bleeder and keep a wrench handy to crack it open. Instruct the person helping you inside the car to slowly pump the brakes a couple of times, then hold the pedal down firmly. When they are holding it down, crack the bleeder open, then close it immediately. Repeat this process until no air comes out of the tube. Continue this process on each corner of the car. For calipers with two bleeders, start with the outboard one first. Throughout this process, regularly top off the master cylinder reservoir with fluid, and check for leaks.
|WHERE THE MONEY WENT |
|Description: ||Part No.: ||Price: |
|Wilwood big brake kit ||140-10220-D ||$2,018.52 |
|Wilwood master cylinder* ||260-9439-BK ||$259.14 |
|Wilwood brake lines ||220-7056 ||$66.61 |
|Wilwood six-pack brake fluid ||290-2210 ||$51.77 |
|Total Control Products spindles ||SPND-01 ||$359.00 |
|Total Control Products hardware ||SPND-02 ||$25.00 |
|Bumpsteer Kit ||TEIR-14 ||$269.00 |
|Brake Bleeding Kit ||$8.00 |
|Misc. lines and fittings ||$10.00 |
|Total: ||$3,067.04 |
|*Special order required by Wilwood for direct fit |
Here is what we had to start...
Here is what we had to start with. There were hundreds of thousands of Mustangs produced in 1966 with this setup, so this may be a familiar sight.
The first step is to remove...
The first step is to remove the spindle. This involves unbolting it from the tie-rod end. We will be replacing the tie-rod end assembly, so we removed it completely.
To detach the spindle from...
To detach the spindle from the control arm, back the ball joint nuts all the way out. If the ball joint doesn't release the spindle, put the nut back on backwards to give yourself a solid place to tap with a ball-peen hammer. The vibration from the hit should release it immediately.
Here is the new spindle. The...
Here is the new spindle. The Wilwood caliper brackets bolts right on in two pieces. Don't forget to replace the cotter pins when installing the new spindle.
Unfortunately, we found that...
Unfortunately, we found that the six-cylinder car's steering components are not compatible with parts intended for a V-8. The drag link is substantially longer on the straight-six cars, so the inner tie-rod ends are proportionally shorter. Also, the thread diameter for the adjuster is different, so you can't simply swap the outer ends. We will be replacing the whole assembly with a rack-and-pinion unit next.
Use Loctite when assembling...
Use Loctite when assembling the hubs and rotors. The hardware that comes with the brakes is pre-drilled, and should be safety-wired after being properly torqued. If you don't feel confident enough to do it yourself, any good speed shop should be able to do it for you.
After the rotors are assembled,...
After the rotors are assembled, you'll need to install the bearings. If you don't have a professional bearing packer, you will get to do it by hand. Put a generous glob of high-temp wheel-bearing grease on your gloved hand, and scrape the edge of the bearing into it, forcing it through the rollers and out the top. Keep doing this until grease has been forced through every orifice.
Once the inboard bearing is...
Once the inboard bearing is placed in the hub, install the seal that captures it. A 2x4 and dead-blow hammer do a great job of installing the seal if you don't have specialty tools. Wipe a small amount of grease on the base of the spindle to keep the seal from hanging up during installation.
Once the rotor assembly is...
Once the rotor assembly is placed onto the spindle, slip the outboard bearing, washer, and nut on. To properly adjust the wheel bearings, tighten the nut while spinning the rotor until it binds slightly. Back the nut off 1/6 to 1/4 rotation, depending on where the cotter pin hole is. This ensures the bearings have been set, and that they won't overheat and fail.
Now you are ready to install...
Now you are ready to install the caliper. It slips over the studs on the caliper bracket over the rotor. Measure the distance between the rotor and the inside surface of the caliper to determine that it is centered. Use the shims supplied by Wilwood until the measurements are as close as possible. At this point, you can slip the pads in. To help keep them from making noise, apply "disc brake quiet" to the areas where the caliper contacts the pad, both on the backing and the sides of the pad.
When replacing a master cylinder,...
When replacing a master cylinder, one option is to bench-bleed it. You can pick up a kit that has all the fittings and tubing necessary. Install the fittings and tubes into the outlets you'll be using on the master cylinder. Then direct the tubes into the reservoir and fill it at least halfway with fluid. Push the rod in repeatedly until there isn't any air passing through the tubes.
The Wilwood master cylinder...
The Wilwood master cylinder bolts directly to the firewall and pedal assembly, just as the factory one does. It uses two bolts through the firewall, and a round clip to attach to the pedal. The rod is adjustable, so match it to the length of the old master cylinder. Our car used a junction block to divide front and rear brakes, but with the new dual reservoir master cylinder, we had to plug the old rear outlet and adapt the front splitter.
The best of brakes won't do...
The best of brakes won't do anything unless it has some good rubber to connect it to the ground. We chose Vintage Wheel Work's V60 17x8-inch wheels with BFGoodrich R1 245/40R17 tires, mounted by our friends at Solo Tire of Orange, CA.