There’s no question that when modifying the C4 or C5 Corvette, the most overlooked system on the vehicle is the brake system. Everyone wants to accelerate from 0 to 120 MPH faster than the next guy, but what about 120 to 0?
It’s possible the availability of components is partly to blame for this oversight. After all, for every 50 companies that offer horsepower upgrades, there are probably 10 that offer proven brake system performance. One of the companies that excels in packaging and selling C4 and C5 Corvette Brake Systems is Zip Products, Inc., 8067 Fast Lane, Mechanicsville, VA 23111, 1-800-692-9632.
What’s appealing about Zip is that they offer more than just high-end competition brake systems. They are very conscious that not everyone wants to or needs to replace their entire brake system. they simply want to improve the factory system. Zip offers many affordable up-grades ranging from brake pads to a line pressure bias spring to the topic at hand, stainless steel brake lines.
To refer to them as brake lines is a bit of a misnomer; they’re really high-tech hoses, and that’s due to their construction. At the center is a flexible Teflon hose that seals in the brake fluid, just like OE brake hoses. The benefit is found in the outer shell. The Teflon hose is encased by a stainless steel braided shell. This is what gives the hose its strength and durability and is why they’re referred to as lines and not hoses. This strength and durability is precisely why stainless steel lines have been preferred over rubber hoses on race cars. However, just because a part is on a race car doesn’t mean it should be on a street car. Conversely, that doesn’t mean it shouldn’t be either.
Simply put, stainless steel brake lines are superior to the original equipment rubber brake hoses. Over time, rubber hoses dry out and crack. This leads to leaks and an eventual rupture. Granted a bad hose is usually discovered long before it bursts and under normal driving conditions it does take considerable time for a hose to reach failure. However, if the most aggressive driving you do with your Corvette is in a car show parade, your factory hoses are fine. Just have them inspected when you get your pads changed out at 60 or 80,000 miles. For those of you who are only used to changing brake pads at 5 to 10,000 miles (or less), get rid of those hoses and install a set of stainless steel lines like those sold by Zip Corvette Parts.
Whether you’re aggressive on the street or auto-crossing on the weekend you’ll enjoy the benefits. Most notable is a firmer and more consistent brake pedal. This comes from the strength of the stainless steel shell. With rubber, every time you stab the brake pedal the hose balloons slightly under the extreme internal hydraulic pressure. You will feel this ballooning as a soft brake pedal. Now add to that the high temperatures generated during heavy braking and the result is braking inconsistency. As the temperature goes up so does the flexibility of rubber and therefore more ballooning. Compound this with thousands of cycles and this is in part why rubber hoses eventually fail when subjected to constant aggressive braking. In addition to a firmer, more consistent brake pedal, you’ll also realize a higher brake pedal. Simply put, less pedal travel is required to generate a desired brake pressure. When the rubber hose expands, the internal area of the brake system is increased. That is why extra pedal travel is required to bring the system up to a given pressure. All these benefits usually parlay themselves into more confidence in your brakes, resulting in quicker times at the auto-cross.
The following installation procedure was performed on a new C5 Corvette, however the steps shown here apply to C4 Corvettes as well. There is no significant difference to the C4 and C5’s brake hoses and connections. The disassembly steps are shown at the rear, while the assembly is at the front. Now on with the corvette stainless steel brake hose installation.
01: It is irrelevant which end of the brake hose you remove first. We choose to start at the frame mount where the hard line terminates. Before we blindly start disassembling things, let’s look at what makes up this junction point. There is an L-bracket bolted to the chassis and in turn is what the hose end mounts too. The bracket plays a dual role by restraining both the vertical and rotational movements of the hose end. Not only do you not need to unbolt the L-bracket from the chassis, your task will become tougher if you do. Additionally, by leaving the clip in place while disconnecting the hard line, the bracket will act as a hands-free wrench. The exception to using the bracket as a wrench is if your junction is rusty. The bracket may not be strong enough to counteract the torque input required to loosen the hard line fitting. You will want to use a 16mm wrench on the hose end to offset the torque input at the line nut. Also, and in addition to a penetrating spray, you should use a line * wrench instead of a standard open-end wrench on the line fitting.
* A line wrench is designed to grab as much of the fitting as possible. Its cutout is just large enough to fit around the hard line. If your fittings are rusty use a line. You do not want to ruin the hard line nut. This job gets a little messy right from the start, so to prevent a puddle of brake fluid on the ground, lay down some newspaper or a drain pan. Use a 13mm wrench to completely remove the hard line from the hose end. As the beneficiaries of working on a new C5, we where able to use the L-bracket as our second wrench.
02: If you’re working in a dirty environment, wrap a shop rag around the line’s end. This will keep dirt out and help absorb what fluid may continue to gravity bleed from the line.
03: A standard flat blade screwdriver works best to remove the clip. Press it into the middle of the clip and pry outward while wiggling the screwdriver back and forth. You may find clip removal easier if you hold the hard line down and away.
04: The banjo fitting at the caliper is far easier to deal with. All it takes is a 13mm wrench to loosen the bolt and you should be able to spin it out by hand. This is another source for fluid drips, so be prepared.
05: The factory banjo fitting is sealed to the caliper with a thin copper washer, identical to the one that comes with your new lines. If it has mated itself to the caliper, be certain to remove it. You don’t want to reuse it, or worse yet install the new one over top of it. Don’t be concerned if brake fluid keeps dripping on the sealing area, just make sure it’s dirt free.
06: It is physically possible to install the new caliper fitting incorrectly. The caliper side of the fitting has the highest thread count, while the side with the steep-angle chamfer is meant to seal the hose end. Don’t forget to install the new copper washer.
07: After threading the fitting in by hand use a 5/8-inch wrench to secure it. Once tight, do not loosen this fitting. That could compromise the sealing capabilities of the washer. They work best if they’re compressed only once.
08: Prior to threading the hose to the fitting make sure there is no dirt on the sealing areas. Check the external chamfer on the fitting as well as the internal chamfer of the hose end.
09: This part of the job is not brain surgery, but you don’t want to just “gorilla tighten” the hose end to the caliper fitting. It is possible to over tighten the hose and crush the chamfer. Hose position is also important. Use a 3/8-inch wrench to keep the hose in line (parallel) with the caliper and a 1/2 inch wrench to tighten the hose nut. Unlike with the copper washer set up, here is a good place to use a loosen and tighten technique. After bringing the hose nut down snug the first time, back it of and snug it again. Repeat this step two or three times. End the sequence with a slightly greater finish torque. Be sure to keep the hose aligned through these steps. After the hose is tight is not the time to align it to the caliper.
10: This is the correct hose to caliper alignment once the installation is complete.
11: In the rear, rotate the hose end slightly toward the rear of the vehicle. This will allow for easy access to the brake bleeder. This is not an issue on the C4 Corvettes.
12: You’re now ready to connect the stainless hose to the hard line. Start by feeding the hose end through the L-bracket and then thread the hard line fitting into the hose end. Leaving the clip off makes this procedure easier.
13: With the hose and line finger tight, now is the time to install the clip. Notice how the ends of the clip turn up. This side of the clip needs to face the hard line. That configures as in the front and down in the rear. You should be able to get the clip started by hand, but a soft tap from a hammer may be required to fully seat it into its groove.
14: Due to the configuration of the new hose end, the L-bracket will no longer serve as a second wrench. Consequently, to tighten this fitting you will need two wrenches. Use a 13mm on the hard line fitting and an 11/16-inch on the hose end. Just as at the caliper, you don’t want to over tighten this fitting.
15: It is very important that the hoses are installed in the proper configuration. After installation, both the front and rear hoses should follow this general path. This will ensure that no undo stress and strain will be placed on the hose ends when the wheels are turned or the suspension goes through its travel.
After all four of your stainless steel hoses are installed, it’s a good idea to clean up the connections and check for leaks. Using a can of brake cleaner, rinse away any residual brake fluid. Then pressurize the system by pumping the brake pedal several times. If any of the connections leak, try just a little extra torque first. If a leak persists, disassemble that connection and check for contaminants. Once you’re sure there are no leaks, bleed the brake system. Refer to your shop manual for the factory recommended bleeding procedure. After bleeding each corner, perform a final cleaning with brake cleaner.
Brake Line Replacement: 1984-2004 C4 & C5 Corvette Stainless Steel Brake Line Installation
Source: Zip Corvette Parts
8067 Fast Lane | Mechanicsville, VA 23111 | (800) 962-9632
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