Certain aspects of your Cobra build are likely to have you scratching your head and giving you the notion that you’re in way over your ability level. If you’ve never bent fuel or brake lines and installed them in a car’s chassis, this could be one of the most daunting challenges for you.
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Factory Five Racing supplies all the fuel and brake lines, as well as all of the fittings, insulated chassis hangers, and rivets for accomplishing all of the fabricating. Other kit manufacturers also supply all of the materials for doing your own chassis plumbing.
As with anything, breaking a big task into small logical steps can ensure progress through the phases of the fabrication until the brake and fuel lines are all bent, fastened to the chassis, coupled together, and fully installed. We divided this process into easy steps and were able to accomplish the fuel line and brake installation, despite the fact that this was just our second time plumbing a chassis.
The more basic and repetitive work, such as applying Sharkhide and silicone, drilling, and riveting aluminum panels into position are good for breaking up the difficult tasks. Accomplishing the rudimentary tasks builds confidence in your ability to take on the more complex work. The satisfaction of having something else done also brings with it the very real notion that you’re that much closer to having the entire car built. There really is a psychological boost that comes from seeing forward progress.
Installing the Fuel Tank
There were many occasions during our Cobra build project where we fooled ourselves one way or another. Let me explain. At first glance it seems that installing the fuel tank, for example, is very straightforward. If you look at the opening in the chassis behind the independent rear suspension, you might conclude something like, “Hey, there’s plenty of space; putting the fuel tank in that opening should be a snap.” That’s what we expected. But I’m here to tell you that it wasn’t that easy, but after a prodigious struggle, we did install that darn tank.
Project 1: Fuel Tank Installation
Step 1: Inspect Fuel Tank Assembly and Required Tools
If you’re building an FFR Mk4 roadster, you need all of these items for installing the fuel tank. If building another manufacturer’s kit, the components are very similar: OEM fuel tank components, fuel strap fasteners (not shown), secondary body fasteners assembly, fuel line components, fuel lines (not shown), 9/16- and 5/16-inch-deep sockets, ratchet, 7/16-inch wrench, hammer, marker, punch or flat-blade screwdriver, rubber mallet, 3/16- and 5/16- inch hex keys, floor jack, light lubricant, drill, 1/4-inch drill bit, and a buddy.
Step 2: Inspect Fuel Strap Fasteners and Plastic End Caps
These four fuel strap fasteners with the locknuts and the washers may look all innocent and easy to work with, but they’re not. Actually, these fasteners work fine. But the fuel straps are made of spring steel, hold the fuel tank in place in the back of the chassis, and were difficult to stretch around the tank to get the tank installed.
Step 3: Install Rubber Fill Neck Gasket
Before strapping the fuel tank into place in the chassis, install all of the components that go into the fuel tank. First, insert the large rubber filler neck gasket in the side of the fuel tank. By hand, place the rubber vent gasket in a small hole on the top of the fuel tank.
Step 4: Install Vent in Fuel Tank
To aid in the installation of the filler neck, apply some lube before pushing this white plastic vent into place in the vent gasket atop the fuel tank. Spray some WD-40 or other light lubricant on the plastic vent. With sufficient lubricant on the plastic, push the vent into place inside the rubber vent gasket on the fuel tank. The vent should go in firmly but without too much effort. Set the rubber O-ring gasket properly into position before installing the fuel pump pickup. The O-ring gasket is held down by the fuel pump pickup retainer ring and the fuel tank.
Installing the Fuel Pump
The Factory Five Racing Mk4 Complete Kit includes all the components required for installing your fuel system, except the fuel pump. There’s a good reason for that. If you’re going to use a carburetor on your engine, you can either use the original-style mechanical fuel pump that is at the front-bottom driver-side corner of a Ford V-8 small- or big-block. Or you can use an electric fuel pump that’s either externally mounted or located in the fuel tank. Your Mk4 Complete Kit includes 5/16-inch hard fuel-supply lines and 1/4-inch hard fuel-return lines. Also included are flexible rubber fuel lines in the same sizes, with quick connects for making the connections to the engine and fuel tank from the hard lines. If you’re going to use throttle-body electronic or stack-electronic fuel injection, you must use an external or internal electric fuel pump. The fuel lines supplied in any kit are sufficient for supporting an engine that has up to 300 hp. In other words, the lines are big enough in diameter to flow sufficient fuel to your carburetor or electronic fuel injection system if your engine makes less than 300 horses. If your engine produces more than 300 horses, these supplied fuel lines won’t flow enough petrol. You are better off using an in-tank electric fuel-pump that can flow an abundance of fuel without overheating or burning out. Inline external electric fuel pumps are not as efficient at pumping the fuel up to the EFI or carburetor as an in-tank pump; they tend to overheat. Since in-tank electric fuel pumps are immersed in cool fuel, they don’t overheat. That’s why every modern automobile has in-tank electric fuel pumps.
We initially fought this simple logic. We already had everything supplied from Factory Five Racing, so we figured we could use it. But, the hard truth was that the engine we were having built produced about 500 hp, so both the electronic fuel injection system we were employing and the electric fuel pump better be up to snuff.
In the end we did what any car enthusiast should do. We called 2 These four fuel strap fasteners with the locknuts and the washers may look all innocent and easy to work with, but they’re not. Actually, these fasteners work fine. But the fuel straps are made of spring steel, hold the fuel tank in place in the back of the chassis, and were difficult to stretch around the tank to get the tank installed. Inspect Fuel Strap Fasteners and Plastic End Caps 3 Before strapping the fuel tank into place in the chassis, install all of the components that go into the fuel tank. First, insert the large rubber filler neck gasket in the side of the fuel tank. By hand, place the rubber vent gasket in a small hole on the top of the fuel tank. Install Rubber Fill Neck Gasket 4 To aid in the installation of the filler neck, apply some lube before pushing this white plastic vent into place in the vent gasket atop the fuel tank. Spray some WD-40 or other light lubricant on the plastic vent. With sufficient lubricant on the plastic, push the vent into place inside the rubber vent gasket on the fuel tank. The vent should go in firmly but without too much effort. Set the rubber O-ring gasket properly into position before installing the fuel pump pickup. The O-ring gasket is held down by the fuel pump pickup retainer ring and the fuel tank. Install Vent in Fuel Tank CHAPTER 9 72 HOW TO BUILD COBRA KIT CARS + BUYING USED Aeromotive directly. Aeromotive is the premier manufacturer of electronic fuel delivery systems for auto race engines, marine applications, and high-performance show and street automobiles.
Aeromotive’s director of marketing communications, Jesse Powell, gave us the hard and cold facts. To adequately supply enough fuel for a 500-hp engine, the minimum requirements are an in-tank electric fuel pump and 3/8-inch-diameter (-6) fuel lines. Jesse prefers his customers use a 1/2-inch-diameter (-8) supply line. However, he said we’d be perfectly safe using 3/8-inch-diameter supply and return lines and one of the company’s in-tank Aeromotive fuel pumps, in addition to an Aeromotive inline fuel filter.
From a pumping standpoint, our fuel delivery problems were solved. We ordered the appropriate Aeromotive products and did some investigating regarding getting the correct-diameter hard and flexible fuel lines.
Project 2: Fuel Pump Installation
Step 1: Wire Fuel Pump
We decided to use an in-tank fuel pump, so we needed to have the Aeromotive electric pump wired to the NAPA fuel pickup. Dennis Clark, owner of Carlsbad Automotive Technology, wired the pump and installed it in the fuel pickup basket for us. We opted to have a professional auto electrician perform this operation, because we wanted to be certain that this was done correctly. The electric fuel pump is surrounded by fuel, so we wanted our pump to be 100 percent wired and grounded correctly.
Step 2: Install Fuel Filter on Pump
Here’s what the Aeromotive intank fuel pump and the NAPA fuel pickup looks like. A required modification was to have 3/8-inch threaded pipe fittings welded to the end of the supply and return lines on the fuel pickup. Warner’s Mufflers in Oceanside, California, provided the precise welding. Snap the friction-fit cloth filter on the bottom of the fuel pump. This filter makes it quite a challenge to insert the in-tank pump and pickup basket assembly into the fuel tank. If the engine in your Cobra replica makes less than 300 hp, you can follow the directions in your kit’s assembly manual and use the supplied components.
Step 3: Install Mounting Collar
With the fuel pickup in place in the fuel tank, slide the mounting collar into position and tap it into place with a punch and a hammer.
Step 4: Install Fuel Level Sender
Installing the fuel level sending unit is similar to installing the fuel pickup, although it’s easier than with the fuel pump and filter sock. Install the O-ring before placing the fuel level sender in the tank. Tap in the mounting collar (clockwise), after the sender is installed.
Step 5: Install Retaining Bracket and Drill Tank Flange Hole
Spray some light lubricant on the fuel-filler neck tube’s rubber gasket, then fit the end of the filler neck into the gasket’s side of the tank. Slide the retaining bracket onto the fuel filler tube. With a Sharpie, mark where it needs to be installed on the fuel tank. Drill out the hole with a 1/4-inch drill bit.
Step 6: Attach Retainer to Tank
Use the supplied 1/4-inch bolt and locknut to attach the fuel neck filler tube retainer bracket to the tank flange, which is tightened with the appropriate-size wrenches.
Step 7: Install Plastic End Caps
You may need to use a bit of gentle persuasion in the form of a rubber mallet when pushing on the four plastic end-caps that cushion the fuel tank flange from its tubular steel-framed location in the rear of the chassis.
Step 8: Install Rear Fuel Straps
Attach the rear strap to the rear of the chassis with the supplied fasteners. The passenger-side strap is longer than the driver’s side, because it has a longer distance to stretch around the groove in the passenger’s side of the fuel tank. In the FFR Mk4 assembly manual, the instructions advise to use a floor jack to raise the fuel tank into position. We used a floor jack, our rolling shop stool, a plastic drum, and a piece of wood for propping the tank in order to attach the straps. You need to coerce those somewhat flexible spring steel straps to the front attachment points in the chassis. (The driver’s side is easier than the passenger’s side.) For the passenger’s side, get the strap close enough to install the front fastener and locknut. Use a wood 2 x 4 and the floor jack to jack directly under the steel strap so that it stretches as far as possible. Use vise-grip pliers to close the gap between the strap and its attachment point, which enables you to finally tighten the locknut to the bolt.
Step 9: Install Rear Fuel Straps
You may have to wrestle a bit with the fuel tank, before you are finally able to securely attach all four-strap fasteners fore and aft. As you might find in the building of your Cobra kit, some of the jobs that appear easy are actually the difficult ones. And the ones you expect to be challenging can sometimes be simple.
Adding Cockpit Aluminum
Now that our muscles have healed from the strain of installing the fuel tank, we move to the satisfying task of riveting-in some sheet aluminum in the Cobra’s cockpit.
Project 3: Footbox Installation
Step 1: Gather Tools and Materials
With the addition of Sharkhide protectant applied to the sanded aluminum panels, these are the tools required for installing the aluminum: drill, 1/8-inch drill bit, rivet gun, silicone, number-8 self-tapping screws, caulking gun, number-8 hex nut driver, ruler, marker, brake cleaner, acetone, and rags. Work with the mounted aluminum panels, the packaged aluminum, and the secondary body fasteners provided by FFR (or other kit manufacturer).
Step 2: Install Passenger’s Footbox Top
Mark and drill the holes in the top flat surface only. Silicone and rivet this panel only along the bottom of the 2-inch-square frame crossmember. Use two number-8 sheet-metal screws to hold the panel temporarily along the other small chassis tube. In most cases, you space the rivet holes every 2 inches, which may mean you need to purchase additional pop rivets. Also, if you have a wide frame tube, drill two rows of rivets with 4-inch spacing and stagger the two rows 2 inches (shown here).
Step 3: Install Transmission Tunnel Cover
You should have no trouble finding the A-shaped transmission tunnel piece; it has a very distinctive appearance. Drill, silicone, and rivet this panel into its transmission-tunnel home within the cockpit.
Step 4: Mount Passenger’s Footbox Inside Wall
Find the passenger’s footbox inside wall. Mark, drill, silicone, and rivet the panel to the front-tunnel A-panel and the top of the passenger’s footbox.
Step 5: Install Passenger’s Footbox Wall
Silicone the panel and install with temporary screws before drilling through both panels and riveting them in position in the passenger’s footbox. In addition, you need to apply silicone to footbox floor. The passenger’s footbox floor resides atop the flanges from the footbox walls. Silicone the wall flanges and rivet the footbox floor into place on the passenger’s side.
Step 6: Fasten Outer Footbox Top
Another unique-looking aluminum panel is the outer passenger’s footbox top. Silicone the flange that’s located between the outer top and the outer wall. Use number-8 sheet-metal screws to attach the two components. Then apply silicone to the remaining flanges and install the outer wall/top of the passenger’s footbox with the supplied rivets. Be sure that the rear edge is flush to the chassis and free of the door hinge before you rivet the panels.
Step 7: Apply Corrosion Protection
Rather than powdercoat all 62 aluminum panels, you may opt to use Sharkhide protectant. After sanding the exposed side of the aluminum, apply Sharkhide to the passenger’s floor bottom. Since it’s the next panel to be riveted, mark, drill, apply silicone, and rivet the passenger-side floor next. The FFR aluminum panels fit extremely well. You may need to trim a few edges here and there. When working with the panels, avoid cutting yourself on a sharp edge.
Step 8: Apply Silicone to Chassis and Floor
Apply plenty of silicone to the chassis where the floor rests on the chassis. Don’t rivet to the round chassis rails, but do apply silicone to all the rails. The top edge of the tunnel does not get riveted yet, though use silicone here as well.
Step 9: Rivet Passenger’s Floor to Chassis
A pneumatic riveting gun makes this job much easier. Alternatively, your hands can get a great deal of exercise, if you use a manual gun as we did.
Step 10: Install Driver’s Footbox Floor
The only surface that isn’t drilled yet is the outer flange. Otherwise, be sure to drill, silicone, and rivet the floor to the chassis rails. This job isn’t very challenging. To properly position the floor in the chassis, you need to gently flex the aluminum panel in on itself to put it in place. After it is in position, we didn’t need to trim any edges. We imagine the same sort of success for you.
Step 11: Rivet Driver-Side Floor
With the driver’s floor in position and aligned with a few temporary screws and a punch or two, rivet the floor into place.
Step 12: Install Side Floor and Footbox
A pneumatic rivet gun makes riveting this panel into position much easier and quicker. Take your time to ensure that the panel is properly aligned on the frame rails, so that the rivets firmly anchor the panel to the frame. After all, the driver’s seat will be placed above this panel.
Step 13: Fasten Side Outer Walls
The driver- and passenger-side (shown) outer walls are the next panels to receive the drill, silicone, and rivet work.
Step 14: Install Inner Foot Box Wall
If you’re building an FFR Mk4, there is a different driver-side inner footbox wall to accommodate a Ford 4.6-liter V-8 engine. Consult the Factory Five assembly manual to identify the wall to use if your powerplant of choice is the 4.6-liter Ford unit. Otherwise, install the wall as shown here. The front flange tucks behind the front wall that was previously left unriveted. Use some silicone on both sides of this flange, drill, and rivet.
Step 15: Install Rear Tunnel Cover
Mark, drill, apply silicone, and rivet the rear tunnel cover, also called the U-joint cover.
Step 16: Install Rear Corners
Given their triangular shape, the cockpit rear corners are more challenging to install. First, mark and drill the corners on their bottom flange where they meet the chassis. Then silicone and rivet these wellengineered aluminum panels in their place on either side of the U-joint cover.
Step 17: Install Rear Wall
Mark, drill, apply silicone, and rivet the rear cockpit aluminum wall to the Mk4 chassis.
Installing Fuel Lines
You have some decisions to make before you fabricate and install your fuel lines. If you’re like us and you’re using a high-horsepower small- or big-block V-8 to power your Cobra replica, you need to custom fabricate larger-diameter lines.
We initially visited a few local auto parts stores to check out the fuel lines they sold, but nothing met our custom requirements. We wanted to run stainless-steel hard lines and stainless flex lines with Teflon liners for our ultimate Cobra build. After doing some investigating at several auto components specialists in our area, we found a hydraulic systems and components shop in nearby San Marcos called Rupe’s.
First the experts at Rupe’s hooked us up with 3/8-inch (-6) pre-bent stainless-steel fuel supply and return hard lines. After we installed the lines and bent them farther for a custom fit, we then had Rupe’s fabricate the stainless Teflon-lined flex lines and all fittings to the appropriate length for the fuel tank hard lines.
We didn’t purchase the flex lines for hooking up the hard lines in the engine bay to the engine’s Holley Avenger electronic fuel injection until after we had shoehorned the engine and transmission in the chassis.
Project 4: Fuel Line Installation
Step 1: Inspect Fuel Lines and Components
If your mill makes fewer than 300 hp and you’re building an FFR Mk4 Complete kit, consult your FFR assembly manual. We used Rupe’s stainless-steel hard and flex lines with fittings that are 3/8-inch diameter for both the supply and the return sides. We also used an Aeromotive in-tank high-performance racing fuel pump, a NAPA in-tank basket/fuel pickup that has had 3/8-inch fittings welded to the supply and return sides, an Aeromotive inline high-performance fuel filter, and NAPA insulated fuel line clips. The tools we used include: tube bender, 3/16-inch drill bit, drill, rivet gun, Sharpie marker, tape measure, and some of the OEM fuel tank components. There’s also a third fuel line in the photo that doesn’t match the other two. It was used as a template to bend the Rupe’s stainless-steel hard lines.
Step 2: Install Inline Fuel Filter
There are myriad places to install the Aeromotive filter, but the most accessible is along the rear corner of the passenger-side frame rail. Being careful to mount the Aeromotive fuel filter so that it isn’t going anywhere, use a large round insulated clamp, drill the frame rail, and use a 3/16-inch rivet to hold the fuel filter firmly into place.
Step 3: Route Fuel Lines
Being careful not to have the fuel lines touching each other or rattling against the FFR frame rails, rout and attach the stainless-steel hard lines, both supply and return, next to each other with the riveted and insulated fuel-line hangers holding them to the round passenger-side frame rail. One thing we should mention is that these hydraulic-application hard lines and flex lines are rated for several thousand pounds of pressure—much more pressure than even the Aeromotive racing fuel pump can dish out. The lines and the fittings are not going to leak.
Step 4:Route Fuel Lines
Rupe’s custom-fabricated our stainless hard lines to our specifications, with high-pressure fittings at each end. We also asked them to bend the stainless. Notice how nicely they wrap around the front of the passenger-side foot box. To do this yourself, accurately mark where to bend the lines with a Sharpie and then use a tube bender, the same kind used to bend brake lines.
Step 5: Install Flex Lines
With the engine installed, measure the distance from the hard lines to the Holley Avenger throttle-body electronic fuel injection atop the engine and order some stainless flex lines. Warner’s Mufflers in Oceanside, California, welded-on 3/8- inch male pipe fittings to the fuel pickup at the fuel tank. The flex stainless-steel fuel lines have the Teflon liners to our measurement specs, complete with the female leak-free fittings. Be sure to securely fasten all the flex-line fittings to the hard-line fittings with the correct-sized wrenches. If you do, these hydraulic high-pressure lines don’t leak!
Step 6: Install Return Flex Line
To minimize the number of connector fittings, the return line should be longer than the supply line. Remember that the supply line has an Aeromotive fuel filter in the middle of it, which prevents you from running hard lines of equal length. Be smart when plumbing your Cobra replica with the fuel lines. The lines must be well away from any moving components and they must be held away from each other and from the frame to prevent rubbing and rattling.
Building Brake Lines and Installing Master Cylinders
If you’re constructing an FFR Mk4 Complete Kit, you’re at the point in the build where you mount the master cylinder reservoir. Factory Five supplies two nice Wilwood reservoir kits complete with all the fittings and hoses for doing the job.
Our challenge is that we have a tri-pack, brushed-aluminum remote reservoir from Kugel Komponents that needs to go in our Cobra replica.
Project 5: Brake Line and Master Cylinder Installation
Step 1: Use Capture Nut on L-Bracket
Use two L-brackets equipped with two capture nuts to mount the custom brake reservoir system.
Step 2: Rivet Capture Nut to L-Bracket
After drilling three holes to mount the capture nut to the L-bracket, rivet the capture nut in place on the bracket. The L-brackets go behind the firewall in the cockpit-side of the car. You can install the custom remote reservoirs on the firewall. Clever, eh?
Step 3: Mount Platform for Remote Reservoir
To mount the remote reservoirs on the firewall side, use tin snips to cut some aluminum from an unused panel to form a platform mount for the remote reservoirs.
Step 4: Fabricate Brake Reservoir Platform
You can buy a block of aluminum at a steel and aluminum manufacturer that sells to the construction trade. Hollow it out and drill holes in the aluminum to install the brake reservoirs. Use a hole saw and an electric drill. Then use a small hacksaw to finish the job. With the needed area cut out, smooth the edges with a flat file. After seeing all this effort, you may opt to use the supplied Wilwood remote reservoir and install it on the front footbox wall, as FFR advises. But we would still do the custom work; we’re happy with how the system turned out.
Step 5: Install L-Brackets to Mount Reservoirs
Install the enhanced L-brackets for the reservoir mountingblock’s capture nut on the cockpit side of the firewall.
Step 6: Install Brake Reservoirs and Route Brake Lines
The custom brake reservoirs are mounted with that aluminum rectangle for a reason—the aluminum block lets you fill the canisters with brake fluid after the body is installed. Route the rubber brake-line hoses to the front and rear master cylinders using the FFR-supplied fittings. If you need a bit more rubber hose, given the different location of these reservoirs, you can purchase more hose in the same size as FFR’s. FFR advocates using just one master cylinder and routing the rubber hose with a T-connector setup. With these fancy aluminum reservoirs, you have one canister for the rear brakes and a separate canister for the front brakes. You could use the canister in the middle, if you had installed a hydraulic clutch, but we opted for a cable clutch because FFR also supplied the cable clutch components.
Step 7: Install Front Brake Fasteners
For the front brake lines and the front flex lines at the brake calipers, follow the instructions in the Mk4 Complete Kit manual to the letter. Here is the flex line hardware found in the brake line components. The components for another kit may look similar.
Step 8: Mock-Up Flexible Brake Lines
Mockup the flexible brake lines to make sure they’re the correct length. We held ours to the brake calipers and turned the front wheels. FFR recommends installing the brake lines on the driver’s side of the chassis and hooking up the fuel lines on the passenger side. We did as they advised with the fuel lines and brake lines.
Step 9: Mount Laser-Cut Brake Brackets
The laser-cut stainless-steel brake brackets go right behind the upper control arms. Center-punch the holes before drilling.
Step 10: Drill and Rivet Bracket Holes
Drill the marked and punched holes for the brackets. The stainless brackets receive two 3/16-inch rivets to hold them fast.
Step 11: Install Brake Line Adapters
Push the brake line adapters through the installed brackets from the outside in, and install the clips that secure them.
Step 12: Attach Flex Brake Lines
When attaching the flex brake lines, be sure to use a supplied crush-washer on either side of the brake caliper fitting. Then screw the other end of the line to the fitting on the chassis and hand-tighten for now. Screw in and tighten the brake-line T-fitting into the end of the driverside brake adapter with a 1/2-inch open-end wrench.
Step 13: Inspect Brake Lines
Use all the FFR-supplied hard brake lines. The trick is to use the lengths you have—don’t cut any lines. If you cut them, you need to have an expensive line-flaring tool, and you need to be a tube-flaring expert to keep the lines from leaking.
Step 14: Route First Front Brake Line
We used a junction fitting and one of the short brake lines; we didn’t have quite enough brake line to reach the passenger-side adapter. These brake lines bend easy, especially with a proper tubebending tool. You can use a tube bender or the right size can or round item to get the job done. Be careful to keep your bends smooth and kink-free. When you have the line the way you want it, use the small, insulated line clips and the 3/16-inch rivets to fasten the line to the chassis. If this is the first time you’ve bent brake lines, you may wish to practice with your tube bender and some spare line. But the FFR-supplied lines are quite malleable, and it’s hard to make a mistake.
Step 15: Route Second Front Brake Line
Route the other front brake line from the front master cylinder to the T-connector on the passenger. Though there are several ways to route this tube, the recommended method is running the line from the 3/4-inch top tube at the footbox, where the master cylinders are located, to the T-junction on the driver’s side. Drill a 7/16-inch hole just under that top frame tube to run the line through it.
Step 16: Run Brake Lines
Be sure to use the supplied insulated brake-line clips and rivet them strategically to the 3/4- inch tube. Coil the line around a couple times and connect it to the T-junction box. To prevent leaks you’re better off using this method than cutting and trying to properly flare the line.
Step 17: Install Rear Brake Flex Lines
The rear-brake flex lines are installed similarly to the front brakes. If you have an FFR Mk4 with the independent rear suspension, be especially mindful of routing the flex lines away from any moving components (like the CV axles). Also the brake brackets are just regular unfinished steel; use gloss-black Rust-Oleum to prevent any corrosion. Use the supplied crush-washers on either side of the brake caliper bolt. Use common sense when securing the proper-length lines supplied by FFR.
Step 18: Mock-Up Rear Brake Line
For a cleaner look, route the rear brake line from the rear Wilwood master cylinder inside the footbox. The challenge is that you don’t want the brake line to interfere with any of the pedals. Use some wire to form a template of where you bent the actual brake line.
Step 19: Mock-Up Rear Brake Line
This part of the mockup wire shows where it’s real tight and tricky. We managed to form our actual brake line, using this wire as the template. We tucked away the line here and used the insulated clips to mount the line well away from the pedals. If you run your line the way we did, be sure to close up the hole in the bottom of the footbox with plenty of silicone.
Step 20: Route and Secure Brake Line to Frame Rail
Route the brake line along the driver-side frame rail and up the rear corner. Use the insulated clips to secure the lines every 12 or 18 inches. Because we have an IRS chassis, our brake lines are routed differently than an FFR Mk4 with a live-axle chassis. If you need to route your lines differently, keep the tubes away from any moving components and protected from the elements as much as possible.
Step 21: Install Brake Line to T-Connector
As with the front brake line, the line to the T-connector gets a couple coils. We were a little short on brake lines, so we purchased an additional 50-inch line from NAPA (black line in the back). We probably had enough line, but it’s more challenging to run the lines on an IRS-chassis car than on a solid-axle car.
Step 22: Route Brake Line and Fill Reservoir
That extra brake line goes right to the passengerside brake bracket. Remember to use the insulated clips and paint the rear brake brackets with gloss-black Rust-Oleum. For the rear brakes, use two 60-inch lines and one 50-inch line, along with the two flex lines that go to the rear calipers. Tighten all the brake lines fore and aft. Fill the brake reservoir(s) with DOT 3 brake fluid and bleed the brakes while checking thoroughly for leaks. The fluid leaks at the fittings if they’re not sufficiently tight
Written by D. Brian Smith and Posted with Permission of CarTechBooks