Ultimate Brake Guide for Restoring Your Mustang

The braking system is one of the most critical areas of vehicle performance regardless of the level of restoration. The car must have a properly operating brake system for safety and performance. The standard braking systems that came with early Mustangs were able to stop the cars, if only just adequately by today’s standards. Few things can ruin the pleasure of driving an otherwise well-sorted-out car than a faulty or underperforming braking system. Despite numerous upgrades in both technology and materials since these cars were new, I do not cover the extensive upgrades to build a brake system for a typical restomod or pro-touring type of vehicle. I do introduce a few upgrades using Ford factory parts that greatly improve braking on a typical early Mustang, while also enhancing reliability/ durability and maintaining the originality of these cars.

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This Tech Tip is From the Full Book, HOW TO RESTORE YOUR MUSTANG 1964 1/2-1973. For a comprehensive guide on this entire subject you can visit this link:

LEARN MORE ABOUT THIS BOOK HERE

 

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These modifications should be applicable and cost effective for daily-driver or weekend-cruiser projects. They provide overall performance superior to the stock setup, making more frequent use of the car possible. The steps for the front brakes can also be applicable to a show car, with the exception of the rear brakes because it involves too visual a change. In this chapter, I mostly address the primary components of the braking system at the wheels. I briefly discuss other items, such as the ford mustang restoration guide, master cylinder, power brake booster, and brake lines. Always consult the factory service manual for specific information on tightening torques, detailed assembly procedures, etc. I only provide some guidelines for what to watch for and how to best resolve any issues.

Usually, it is more cost effective to replace components than to rebuild them. With a show car, this may not be true if higher judge’s scores for originality is a priority. The extra expense of machining and/or rebuilding are then more practical. Fortunately, many newer replacement parts can still be used for a show car because they are visually similar to the original parts. I point out some instances where this may be possible, and where only original parts will do.

 

 

For this project, we decided to upgrade one of the areas where great progress has been made in terms of improved technology: the rear brakes. The drum setup that originally came with our car was fine for the day, but we wanted better performance that matched our now higher contemporary expectations. Fortunately, Currie Enterprises offers a kit that adapts the much-improved Ford factory rear brake setup from a late model Thunderbird to the 9-inch axle in our 1968. It even allows us to still use the stock 14-inch rims so we can have much-improved performance with only the slightest hint of an upgrade for those willing to look close enough to tell. Here we see these brakes mounted to our rear axle just after welding on the tabs for the new brakes hoses.

Initial Inspection and Evaluation

Brakes wear as a normal consequence of use, so evaluating the braking system primarily involves trying to determine if there is excessive wear, damage, or leakage.

For disc brake systems, deep grooves in the surface of the rotor are evidence of excessive wear and/or damage. A normal rotor surface should be flat with only very fine surface imperfections that can barely be felt by running a fingernail across them. It should turn smoothly with no interruptions or sticking. Any significant grooving means the rotor has to be remachined (if there is enough material/thickness left) or be replaced. Also check for discolored and/or cracked rotor surfaces (a sign of overheating) and warping. The latter is not always visible but can often be felt by turning the rotor on the hub and experiencing intermittent sticking or drag, or a pulsating feel through the pedal. If any of these symptoms are observed, the choice is between remachining (turning) and replacement.

Inspect the seals around the pistons in each caliper for leaks. If there are none it is probably possible to simply clean and/or paint the caliper before reusing it. Always use a new hardware kit (clips, rubber parts, etc.). Check the rubber of the brake hoses for any excessive cracking or signs of leakage. Replace the hoses if there are any signs of leakage whatsoever. If the hoses are reused, it is a good idea to clean them and wipe them down with a silicone protectant.

Last, since the front wheel bearings and grease seals are replaced as a matter of course, it’s only necessary to ensure there is no corrosion at either the bearing pocket in the rotor or on the steering knuckle where the bearing makes contact. If there is substantial rust on these parts, they must be replaced.

Drum brake systems are a bit more complicated to evaluate because they must be disassembled to a greater degree before they can be fully inspected. One of the first telltale signs of a problem is fluid on the backing plate. This is a sign that a wheel cylinder likely needs to be replaced. These are generally easy to find and are inexpensive, so this is no big deal.

The drum is often difficult to remove and is an important indicator of potential problems, such as a high degree of wear. As this wear occurs, a step that tends to grab the edge of the brake shoes is formed, and thus prevents the removal of the drum. Loosening the brake shoes via the adjuster wheel and a few evenly spaced, soft-faced mallet blows to the outside of the drum often helps remove it.

 

Even if the rotors on a disc system appear to be in fine condition, check the thickness of the brake pads for uniformity. Here are new pads on a fourpiston caliper. The pads are uniformly thick from side to side, and about the same thickness, as you would expect with new pads. If the pads that were on the car were wearing unevenly, this could point to a problem with corrosion and/or broken or stuck hardware that needs to be corrected before the brakes are reinstalled. This is one of the reasons such hardware is usually replaced automatically; it solves such issues. As part of the cleaning process, remove any corrosion from parts that are reused; new replacement parts should not have any, or course. Besides changing pads much more easily/quickly, another advantage of a four-piston caliper over a single- or dual-piston design is that the extra pistons ensure the pads press evenly against the rotor and don’t cock to one side or the other.

 

When inspecting the front brakes for the first time, look for any signs of leakage from either the calipers (discs) or the wheel cylinders (drums). If leakage is found, the affected parts need rebuilding (possibly, in the case of a show car only) or, more likely, replacement with new parts. Since most of the small hardware for either type of system will be replaced anyway, the next thing to check is the condition of the rotors or drums for any excessive wear, scoring, grooving, or other damage. In our case, the front brakes were in excellent shape, but we decided to use new replacement parts to benefit from improved design, materials, and technology. For a show-car restoration, you need to match the factory rotor design. Unlike most modern rotors (including the replacements we used), the factory rotors had a stepped design. That design is inherently heavier than the more integrated/modern approach and was a reason why we replaced them. For those building a show car, these original rotors would have been reused after a simple machining operation to ensure flatness and a proper surface finish.

 

Inspect the inner passages of each rotor and remove any dirt or debris. Contaminants inside the caliper inhibit airflow and can cause an imbalance or a hot spot. Cracks or other damage generally mean replacement. Inspect the brake hoses for excessive cracks, wear, or other damage to the surface of the hose. Some superficial age cracks in the rubber are common, but any deeper cracks are not. In a restoration project, you usually replace the brake hoses unless they are in especially good condition. Ours were, so we decided to keep them and simply wipe them down with some silicone protectant later. The hose hardware (clips, copper gaskets, etc.) can often be reused but replace it for a bit of extra insurance. Those interested in improved brake performance, especially pedal response, can consider upgrading to brake hoses wrapped with steel braid. This minimizes hose ballooning and improves response and pedal feel. This isn’t necessary for most daily drivers and would be unacceptable for an authentic show car. For weekend cruisers or where maximum braking performance is desired, this can be a very effective upgrade though it may be justifiable only with an aftermarket brake kit.

After the drum is off, measure to determine if the drum pad material exceeds its minimum thickness specification. If so, it can then be turned to remove any ridge that may have been present, and also to restore a smooth braking surface. If there are no signs of leakage from the wheel cylinder, this part can be reused, but replacing it means a longer service life, especially if it’s the original part. Materials technology for seals, etc., has greatly improved in the last 40 years; newer materials are compatible with most modern brake fluids, including synthetics and synthetic blends. Most of the remaining hardware on the backing plate can be reused after cleaning, assuming there has not been any excessive wear at the points of contact sliding, etc. It is generally a good idea to replace the springs because they tend to weaken over time as a result of fatigue and heat cycling.

 

Inspecting the rear brakes is essentially similar to what must be done at the front. However, there may be differences related to the presence of rotating axles versus the simple, stationary spindles used at the front. A leaking rear axle seal, for example, is much more likely than is a leaking front grease seal. Friction materials contaminated by any such leakage should always be replaced. The presence of a parking brake system also has the potential to cause unique issues, though these are usually only a matter of the cable(s) not fully releasing the brake and are simple to resolve.

 

At the rear of the car, also inspect the interconnection between the left and right brake lines, as well as how each line connects to the backing plate/wheel cylinder. The axle assembly is a pretty stout piece, so there usually aren’t any problems. However, careless repair work and/or vehicle modifications can sometimes constrict or damage the lines. This is especially true where the lines pass by the U-bolts on each side. Look for any fluid leaks at the distribution block, which connects the axle lines with the flexible hose from the body. Don’t be fooled by any gear oil that might have come out of the axle tube vent. Make certain any leaks are from brake lines before you try to tighten the brake line nuts. Use a flare nut wrench to prevent rounding of the edges of the nuts.

New parts for most of the drum brake hardware, except for the pivot arm, the bridge, and the backing plate itself, are available if needed. Even the backing plates can be reconditioned and/or welded to return them to spec if they prove to be hard to find.

The rest of the braking system consists of the master cylinder, power brake booster/diaphragm (if so equipped), hydraulic lines, and pedal assembly. These items can usually be reused after a cleanup if there are no signs of leakage (fluid or vacuum) and the brakes were working properly.

The master cylinder can be rebuilt with new seals, etc., but, unless you rebuild it yourself, it’s often less expensive to simply replace. With a show car, the original master cylinder should be retained but for a daily driver or a weekend cruiser, it is often more practical to simply replace the master cylinder rather than have it rebuilt. The power-brake booster can likewise be rebuilt, but it’s also only practical for show-car authenticity.

 

We had our power brake booster rebuilt because the car had been sitting for 20+ years and we were concerned the internal diaphragm might fail once we began using it again. The cost of a rebuild is usually less than buying a new unit plus you retain authenticity. Take care to bag and tag all of the small parts that go with the booster as these are not easy to find if you lose them. For the rest of the brake system a simple cleaning and lubrication of the pedal assembly is usually all that is required although there should also be a check performed to ensure there is no excessive free play or wear at contact points. Other than perhaps a readjustment of the brake light switch and/or the parking brake there is little else to look after.

 

Our master cylinder and vacuum booster did show signs of leakage, so we knew we would need to address the matter. We’re not concerned with having perfectly matching/original parts on our weekend cruiser, so we decided to get new replacement parts for these. For a show-car restoration, a rebuild is often the preferred choice for authenticity. Besides being more cost effective (in most cases) as well as easier from a logistical standpoint, using new components ensures the best materials technology. Surprisingly, our switch to disc brakes at the rear didn’t require a special master cylinder. The fluid volume of the calipers used in the Currie Enterprises conversion kit is similar to that of the wheel cylinders used in a drum brake setup. This may not always be the case; but, even if a different master cylinder must be used, there are plenty of suitable options. Most of these will directly bolt in with no need for change other than perhaps slightly relocating the brake lines.

The brake lines can almost always be reused unless they are damaged or corroded. For those who would like to make an upgrade from the factory galvanized mild-steel lines, it’s often possible to get direct-fit lines made in stainless steel from companies such as Classic Tube of Lancaster, New York. These lines not only look better than the factory lines, but they also last almost indefinitely, even in cold climates where the roads are salted. This upgrade may not be suitable for show-car authenticity, but it clearly offers a significant and inexpensive benefit for most daily drivers and weekend cruisers.

For the pedal assembly, there is little to do other than possibly replace the rubber pads and maybe a bushing or two if any are worn. For almost all restorations, the pedal assembly is just cleaned, lubed, adjusted, and retained as is.

 

The main issues with the parking brake mechanism are whether or not the cables have been stretched too much through previous use or if they are starting to show signs of corrosion. In either event, they should be replaced with new cables. The pivot points of the short intermediate arm should be lubed after they’ve been cleaned. Also make proper adjustment to the cable collar to ensure correct parking brake function. Since we’ve upgraded our rear brakes to the more contemporary disc setup, we have to adapt the cable ends to match what’s needed with the new parts.

The parking-brake system is also generally just cleaned, lubed, adjusted, and reused as is. Worn or damaged components might require replacement. “Wear” can also include stretched braided-steel cables; they become too long to allow full engagement of the parking brake. If this cannot be resolved by adjustment, buy a replacement cable(s). We had to do this anyway because we converted the rear brakes from drums to discs, but this is common even when the factory parts are retained. These cables are usually easy to find and don’t cost much, but there really is no need to replace them unless they’ve stretched or are otherwise not usable. As with the service brakes, the pedal (or handle) for the parking-brake system generally needs little attention other than cleaning, lubing, and possibly adjustment in most instances. Replacement parts are usually easy to find.

 

Those original front brake parts, which were to be reused, were simply cleaned and painted as necessary for reinstallation. The dust shield gasket can usually be reused if it is carefully removed. If it is damaged, use a new one or make one suitable gasket material with the original as a template. Also check the surface of the spindle (where the wheel bearings make contact) for any surface imperfections or pitting. We ran our spindle through the media blaster to remove the old paint and dirt before painting. This also provided a smooth even surface that is better at holding the bearings in place than a surface that is too smooth.

 

We could have reused our rotors and calipers, but we used new parts for the lighter weight and improved materials. The rotors we chose have been precision ground to ensure flatness and trueness from side to side. This is evident from the pattern on the rotor face. It pays to spend a bit more to get premium parts like these. These perform better and are more durable and reliable as well. We’ve already installed new high-quality bearings in the rotor. The new calipers also benefit from improved materials, especially the piston seals. Always install new caliper hardware with proper lubrication. We didn’t intend to do any extensive high-performance driving, so we chose a high-quality ceramic composite pad material that would be suitable for most restoration jobs because they wear long and reduce dust.

 

The finished front-brake assembly looks great and should deliver both better performance and longevity than if we reused more of the original parts after reconditioning them. The rotor design is clearly different than that of the original parts, but we are not aiming for 100-percent authenticity. We’ve placed greater priority on performance, drivability, and cost effectiveness. This high-quality, direct-replacementpart approach is easier and results in a superior system to one using reconditioned original parts, generally for a lower total/overall cost. Our GT wheels would pretty much hide the calipers from view so we elected not to paint them or the rotor centers.

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This Tech Tip is From the Full Book, HOW TO RESTORE YOUR MUSTANG 1964 1/2-1973. For a comprehensive guide on this entire subject you can visit this link:

LEARN MORE ABOUT THIS BOOK HERE

 

SHARE THIS ARTICLE: Please feel free to share this post on Facebook / Twitter / Google+ or any automotive Forums or blogs you read. You can use the social sharing buttons to the left, or copy and paste the website link: https://www.diyford.com/ultimate-brake-guide-restoring-mustang/

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Disc Brake Conversion Step by Step

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #1

After the studs have been pressed into the axle, install the correct-dimension centering ring around the hub to help center the rotor to the axle centerline. This is critical and prevents misalignment, which could create unwanted vibration and/or poor braking performance. Note how the centering ring has a small lip at the lower edge; this must be located next to the axle. The chamfered edge must be at top.

 

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #2

When assembled with the rotor, the centering ring locates the rotor concentrically with the axle centerline. It also can serve as a pilot for the wheel if it has the correct diameter hub bore. Conversely, the wheel hub bore must be large enough to clear the centering ring or else the wheel won’t sit flat on the rotor hat—a potentially dangerous situation. This view also shows how the raised shoulders on the longer studs act to pilot the rotor hat in combination with the centering ring. The locating ring does the final centering while the studs merely help guide the rotor onto the ring. Since factory wheels from this era are “lug-centric,” the presence of the raised center ring shouldn’t be a factor. The lugs position the wheel and tire. However, if newer hub-centric wheels are to be used, then the dimensions of the centering ring and the wheel’s hub bore must be properly matched.

 

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #3

The caliper mounting plate must be installed over the axle, in the direction shown, before the axle bearing is pressed on. When pressing on the axle bearing, a film of thread locker should be spread over the bearing surface of the axle before the bearing is pressed onto it with a hydraulic press. Once the bearing has been pressed on, it cannot be reused because the inner bearing race has lost material as a result of the interference fit with the axle. After the bearing is pressed on, any such residue as well as any excess thread locker must be wiped off. A thin film of grease should be applied to the area where the axle housing seal contacts the axle to ensure it has proper lubrication when the axle is turned.

 

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #4

Ford used different size axle bearings according to the vehicle application, which can be determined by the appearance of the axle housing ends. Our housing had the smaller size bearings, which is consistent with most Mustangs. Heavier and/or higher-performance cars usually came with the larger bearing housings, which would have a more pronounced step up from the axle tube to the bearing seat. Because the backing plate holes were in the same place, it required different size heads on the backing plate bolts. The larger-headed bolt (left) is the correct one to use with smaller bearing axle housings like ours. The smaller headed bolt (right) is correct for use with axles equipped with the larger bearings.

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #5

The former mounting plate bolts attach to the mounting plate as shown. Insert the correct socket through the hole in the axle flange, which is drilled specifically for this purpose, and torque these bolts down. No gasket is required between the mounting plate and the axle housing because the axle seals perform the needed sealing function. Do not overtighten these bolts because it could warp the mounting bracket and misalign the caliper. At a minimum, this would cause uneven brake wear with the potential for even more severe problems. In some cases, the mounting bracket holes may need to be redrilled to rotate the calipers such that they clear the spring; this cannot be determined until all the parts are assembled.

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #6

When the caliper is installed on the mounting bracket, you can see how much space the package occupies. The rotors sit inward from the axle flange and toward the differential. This provides extra clearance to the wheel in the lateral direction. Note how the caliper mounting bracket and bolts neatly tuck behind the rotor to allow this. The low profile of the caliper is in part due to the type of parking brake mechanism, which moves most of the mechanism inward over the axle tube. This frees space within the wheel and provides the radial clearance to allow the use of 18-inch wheels. The caliper mounting bolts should always be coated with a high strength thread locker to ensure they do not vibrate loose. Since only two mounting bolts are used and they are not especially large, this is especially critical. The correct bolts and locking washers are included in the Currie kit, but the use of a thread locker provides a bit of extra insurance for even more safety.

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #7

The Currie Enterprises disc-brake conversion kit includes new brake hoses, which are required for the new brakes. These hoses each feature a protective sleeve to prevent chafing or other potential damage. The hose attachment to the calipers is common, but a little creativity is required for the connection to the opposing rear brake and the incoming pressure line from the car. Before we can address that, however, we must first secure each hose to the housing by securing the loose end with a tab.

 

MUSTANG RESTORATION:  DISC BRAKE CONVERSION- STEP #8

Position the mounting tab so that the hose is not stressed, yet it is still protected from road debris, exhaust heat, etc. The area where the original factory brake line was located is a good place to use, if possible. Here, we see the hose end reaches the factory line location, yet still has space for the incoming hard line, which comes from the vent tube area. The factory tab needs to be ground off.

When installed, the new hose mounting tab is located the same basic area where the factory hard line was mounted. The new hose is protected and in an unstressed position. The axle tube vent is used to help secure the distribution block that ties the two rear brakes and the incoming pressure line together. Basically, we use Ford factory parts to retain the factory appearance while still gaining functionality for our upgrade.

 

Front Brakes: Installation

Our car came with single-piston front disc brakes, which we felt sufficient for our intended use. These brakes are reasonably effective for typical street driving, but they were not suitable for highperformance driving (I address that later in this chapter). As noted earlier, it generally is more practical to replace the original factory parts than it is to rebuild them, unless you are building a show car. So we simply disassembled the front brakes, cleaned the parts we reused, and bought new replacement parts for the rest. Even though our rotors were in pretty good shape (they didn’t even need to be cut), we decided to go with new ones for the smoother friction surfaces and the improved metallurgy in modern discs. Their design is slightly different than the factory parts. The new rotors also were slightly lighter than the originals; a minor performance benefit, in our particular case. We installed new bearings in the rotors and also new hardware for the calipers. All of these components were direct-replacement items, and thus go in exactly the same way as the original factory parts.

 

For even more braking performance (and a bit extra cost), use the factory four-piston setup to retain OEM look with improved performance over the single-piston design. For maximum braking performance, there are numerous aftermarket options. These can fit virtually any need for an even higher price, but at the expense of the factory appearance. We needed more than the original single-piston caliper, so we used an aftermarket upgrade. For a weekendcruiser or high-performance driving, the four-piston or aftermarket choices are more attractive. The judged show car inevitably stays with the original system.

 

The conversion to discs also requires the installing new, longer wheel studs. These also must feature an unthreaded shoulder so the threads don’t dig into the rotor. This isn’t required with drum brakes because the drum is generally thinner in this area. The best time to install the new studs is before the rear axles are being assembled into the axle housing. It will be necessary to remove the axles in any event because the caliper mounting plate must go behind the axle flange, between it and the axle housing.

 

The Currie Enterprises rear-disc-brake conversion kit for our 9-inch rear axle uses all factory Ford parts from a latermodel Thunderbird. The only new parts are the mounting bracket assembly and the hub centering ring. This system provides dramatically improved braking performance, is lighter and less complex, and fits inside a 15-inch wheel. Serviceability is also improved because the newer parts are easier to source and generally cost less. The only real adaptation required with this kit it the attachment of the parking brake cables and the fabrication of new brake lines on the axle. The same-style master cylinder can be used or reused.

For brake pads, we selected a premium ceramic-based compound, which would not only perform better and last longer than the original factory compound, but should create significantly less brake dust. Make sure you adjust the wheel bearings correctly per the factory service manual. When using new direct-replacement parts instead of rebuilt or refurbished originals, there really is no difference beyond the benefits gained from the newer materials and technology. Just be sure to use good-quality grease on the bearings and keep it and any other contaminants off the friction surfaces. Also spray the rotors with brake cleaner and wipe them down with a lint-free cloth before you install the wheels and tires over them.

For those who may wish to upgrade front brakes to a higher level of performance, numerous aftermarket options are available, from mild to wild. (I do not cover the typical restomod options, other than to say the aftermarket offers very significant gains in braking performance.) Many are very reasonably priced yet still more expensive than the simple direct-replacement approach I’ve shown.

Another option for those who want substantially improved braking performance while retaining a more factory look is to install the factory four-piston front calipers that were optional on various models. These can be installed with minimal effort, although other components besides the calipers need to the changed as well. All of the needed parts are generally available from the various companies that specialize in Mustang restorations, and the total can often be less than the aftermarket alternatives. These don’t match the performance of most of the aftermarket systems, but are a vast improvement over the factory single-piston caliper option or a front drum-brake system. They can also be used in many forms of mild high-performance driving while providing a factory-correct appearance that no aftermarket brake kit can. For ultimate braking performance, aftermarket kits are the only way to go. However, for a weekend cruiser where improved braking performance with a factory look is desired, this is a very viable alternative.

Rear Brakes: Conversion and Installation

While we were content to retain the factory brake setup in the front, we did not feel the rear drums that came with our car would handle the more-frequent driving schedule we had in mind. Drum brakes are less efficient in wet weather than discs and tend to be much more sensitive to adjustment. Discs are, by design, inherently more self-adjusting as they wear. You don’t see many race cars with drum brakes. Discs are also far simpler and easy to service as well as lighter and more effective. There were many good reasons to convert our rear drum brake system to a disc brake system.

 

The finished, painted rear axle assembly with the brakes installed shows the disc brake conversion setup. At this point, we need to determine if the calipers will interfere with the springs. Several factors, including the curvature of the springs and the position of the calipers themselves, determine this. If the calipers need to be repositioned, new holes need to be drilled in the mounting plate to rotate the calipers out of the way. This entails removing the calipers and axles and then pressing the bearings off of the axles, so the plates could be redrilled. New bearings are needed before the axles can be put back in. Fortunately, the likelihood of interference between the calipers and the springs is minimal. It remains possible, however, since it is virtually impossible to anticipate every possible combination of components and their relative positioning (static and dynamic) based on vehicle loading and operation.

We wanted to retain a factory appearance, however, so our options became much more limited. There are numerous aftermarket options available for the rear brakes as well, and though our stock GT-style wheels hid the brakes well, we did not want to go this route, mainly for aesthetic reasons. We also really didn’t need the ultimate in braking capability for this vehicle. We simply wanted to benefit from the advantages of a modern disc-brake system.

We found an alternative from Currie Enterprises in Anaheim, California. It offers a rear disc-brake conversion from a 1991–1993 Ford Thunderbird SC for 9-inch axle assemblies. This not only provides the factory look (albeit a newer factory look) we desired, but it also allows us to still use our original wheels and not have to worry about trying to find special parts when we need to service the brakes. Unlike many of the aftermarket brake upgrade kits, the Currie kit clears 14-inch wheels and does not require any axle modification beyond simply installing the unique mounting brackets for a given application. Other than adapting the parking-brake cables, this really is a cost effective, true bolt-in system.

 

After installing the axle into the car, we found that our new brake setup cleared the springs even though they were somewhat different than the original parts. Since there will be relatively little movement between the springs and the calipers we can be fairly confident there won’t be problems under loaded and/or dynamic operating conditions. While we have not yet resolved the matter of adapting the parking brake cables to the new calipers, we’re confident this can be accomplished in short order.

Compared to using the rear disc brakes from other, newer Ford vehicles (Lincoln Versailles, for example), these are not only more effective and much easier to find, but they also use a common pad that is available in various compounds to better suit your intended use. We went with a premium ceramic-based pad, as with the front brakes. If you don’t want to change the original look of the car, this upgrade is clearly not for you. While it may not be necessary for a daily driver either, it clearly would be a benefit in that case and with a weekend cruiser such as ours.

 

Fabricating custom hard lines for the rear brakes involved little more than using a standard tubing bender plus finding an extended vent tube and a suitable distribution block. The latter parts are pretty easy to source and they bolt right on. Bending of the tubes was a matter of just connecting the ports on the distribution block to the hose ends we had just mounted. For the shorter tube, we included extra bends so the ends of the line would aim directly at their targets. The longer line just followed the path of the original factory line except that it ended at our new hose end. The stock tabs on the housing were used to secure the longer hard line. We used a long-enough jumper hose to compensate for axle travel, and which also fit right into the stock mounting bracket on the body, to connect the pressure line to the new junction block secured by the vent tube.

The only other option for retaining a true early look and higher performance is to upgrade to some of the very rare factory rear-disc-brake setups. The parts for these are difficult to find (unlike the four-piston front caliper option) and very expensive. They also don’t offer the performance and serviceability benefits of the Currie system either. Simply put, if you are going to upgrade the rear brakes of your early Mustang and don’t need the highest performance or want the non-factory look of an aftermarket kit, you really can’t do any better than the Currie solution. It provides better performance, reliability, and serviceability, along with the ability to still use most original factory wheels in a cost-effective and Fordfactory- appearing manner.

Because we upgraded our rear brakes, we also have to make some adaptations to the brake hoses, lines, and parking-brake cables. To finish, I show what needed to be done relative to our rear brake hoses and lines. On a vehicle where the brakes have been kept original these steps would not be necessary; just clean the lines and fittings prior to final assembly.

 

Written by Frank Bohanan and Published with Permission of CarTech Inc

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