As with many car builds, the construction can’t start until the disassembly stops. You might not necessarily think that is the case with a brand-new kit. What makes this a necessity with the Factory Five Racing Mk4 Complete Kit, as well as for other variants of the FFR Cobra replicas, is the fact that the Mk4 kits are shipped with the bodies installed on the chassis.
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Many of the 62 aluminum panels that comprise the cockpit, the trunk, the driver-side and passenger-side footboxes, and the engine bay, are pre-installed.
Typically, one fastener per panel holds each panel in place. So the aluminum panels are put in place, but they haven’t been drilled and riveted yet. That’s for you and your talented crew to perform. At first sight of all those loosely placed aluminum panels, you may feel overwhelmed. Never mind. When you’re marking, drilling, and riveting them into their permanent locations, you feel as though you’re building an airplane. In a sense you are, these FFR Mk4 roadsters are veritable land rockets.
After safely storing away the carpet and the dash, you need to remove the hood, trunk lid, and doors from the chassis. A pair of gloves, 1/2-inch socket, ratchet, 5/8-inch wrench, pair of scissors, and three friends can make this job a snap. Use a secure place to store these body panels where they won’t get trampled on or scratched. The gloves are to prevent you and your buddies from getting fiberglass cuts from any of the body’s or panel’s edges. Since the body is very light, it is possible for two people to lift it off the chassis. However, having a friend on either side to pull the sides of the body away from the frame rails is a big help.
After the doors are inside your house, or in the attic, or somewhere super safe, remove the hood. Our Cobra hood is under my bed. The fasteners are in a marked Ziploc bag with the other body fasteners in a box, and we actually know where that body fastener box is in the garage.
With the decklid stored safely, it’s easy to appreciate that your Cobra is nicely constructed. Before going on to the next step of unfastening bits, take a gander at those virgin aluminum body panels that have been formed by some real car craftsmen, whether they’re Factory Five Racing employees, E.R.A. technicians, or whomever. Okay, that’s enough of a break. The Quickjacks are next.
At this point, we believed we had all of the body fasteners and body panel bolts and nuts removed. With two neighbors standing by for doing light yet careful lifting, we attempted to remove the body off the chassis.
I should mention that just before this exciting step, we placed some wood floor panels on the garage floor. We formed a nice wood pad frame for our Factory Five Racing Mk4 roadster body to repose upon until we need to put it back on the chassis. The FFR assembly manual indicates that it’s also okay to store the body outside. Since we had the garage space, we figured that this curvaceous form should stay inside. The daily drivers needed to be in the driveway for the coming months.
Since the body didn’t separate from the chassis with our first lift attempt, I lay on the creeper and rolled under the car. (The Mk4 chassis/body was on four sturdy jackstands, one at each corner of the frame. So, it was very safe for me to be under the car.) Sure enough, I found a small screw on each side of the body, which holds the back lip of the body to either frame-rail side, a little bit in front of where the openings are for the rear wheels. The FFR assembly manual didn’t mention these screws. Perhaps they are just used in shipment. Regardless, I removed the screws and secured them in the Ziploc bag and box.
With all the fasteners and the Quickjacks in storage, the body lifted off easily. Unfortunately, I didn’t get a photo since I was occupied lifting the nose of the fiberglass body.
Project 1: Disassembly
Step 1: Unbolt Driver’s Door
You need to disassemble parts of the car before you can reassemble it. One of the first steps is to remove the doors. Using a wrench or socket and ratchet, remove the two bolts that hold the door to the hinge. The doors are fiberglass and weigh less than 10 pounds, so one person can do this job without a problem.
Step 2: Cut Door’s Tie-Wrap
Use a pair of scissors to cut the plastic tie-wraps that hold each door closed.
Step 3: Remove Doors
After freeing the two bolts and the tie-wrap, the doors are light and easy to lift and store securely. Place the door fasteners in a Ziploc plastic bag and label the bag, before putting all the body fasteners in a box and storing in a memorable place. With the doors removed, you can see that there are component boxes everywhere. Because our three-car garage was filled with FFR Mk4 boxes and components and a 1934 Ford roadster pickup project in the third garage stall, we stored the doors, hood, and trunk lid in a spare bedroom. But keep in mind that you need a two-stall garage-type area to assemble the Cobra and the area of a single garage to properly store most of the parts.
Step 4: Remove Decklid
There are two hidden hinges, one on either side of the trunk-lid, that hold the lid in place. Use the same socket and ratchet to remove the locknuts from the bolts and secure the fasteners in a marked Ziploc plastic bag, which in turn goes in the body fastener box. The decklid is light (fiberglass) and can be removed by one person, though two are preferable.
Step 5: Remove Rear Jack Stands
Dad removes the rear Quickjacks with alacrity and places the fasteners and Quickjacks in the same Ziploc marked bag and box.
Step 6: Lift Body Off Chassis
Lift the body off the chassis to begin installing the underpinnings of the car.
Aluminum Panel Removal
When we lifted off the Mk4’s fiberglass snakeskin, we were in form-follows-function design and engineering excellence. The aluminum panels nestled among the FFR’s space frame tubular chassis are precision measured, cut, and folded, and fit together precisely. Upon inspection, we immediately recognized a challenge to our building prowess. Panel ends overlap each other. So if they were removed from the chassis, we wouldn’t know where to drill certain panels for riveting. We were looking at an elaborate, 3-D jigsaw puzzle where every piece was the same silver-aluminum color.
In the Mk4 assembly manual, the directions say to mark the panels along the frame so you know where to drill the rivet holes for when the panels are riveted back onto the chassis.
That approach works great for the panels that don’t overlap, but doesn’t work at all for those that do. So, the Smith men made an executive decision to mark all the panels very painstakingly and also indicate where panel ends fit under or over each other. Also, where the panels overlap each other, we drilled the panels before removing them. According to the FFR manual, you can have rivets every 3 inches or every 2 inches. Factory Five Racing provides enough rivets for 3-inch spacing. They also provide a rivetmeasuring/drilling tool that has holes in it every 3 inches. Going with the notion that more is better, we marked drill holes for the rivets every 2 inches.
Final installation of the aluminum panels was a rather complex process, very much like a 3D jigsaw puzzle with overlapping pieces. Therefore, we took great measures (pun intended) to accurately measure, mark, drill overlapping panels, and snap numerous photos showing how the panels go back together. We also used a blue Sharpie marker for the driver’s side and a black Sharpie for the passenger’s side. In hindsight, we really did have a well-engineered plan for ensuring these panels went back in and were relatively easy to silicone and rivet into place. Our master plan for careful aluminum panel fitment went well.
Project 2: Panel Removal
Step 1: Mark Driver-Side Trunk for Drilling
In this case, it is a good idea to work from the back to front, because the upper trunk floor requires drilling. Mark the trunk floor and place a dot every 2 inches. The only panels to be drilled now are the ones that overlap. Otherwise, remove the panels and drill them outside the car. FFR provides an aluminum drilling template that’s pre-drilled with 2-inch-spaced holes on one side and 3-inch-spaced holes on the other side. You simply decide whether you want your rivets to be spaced 2 or 3 inches apart. Factory Five supplies enough rivets for having them spaced 3 inches apart.
Step 2: Clamp Walls to Chassis Tubes
The panel-marking procedure includes drilling those aluminum panels that overlap each other prior to removal. Drill the passenger-side trunk wall. Look closely at this wall and you see we’ve also marked openings that need to be filed or trimmed. These panels fit well, but precise trimming in high spots enables them to fit perfectly, which the ultimate Cobra deserves.
Step 3: Vacuum Clean Work Area
It is very important to keep your work area clean. Make sure the cockpit rear walls align properly. We clamped them to the chassis square tubes prior to drilling, when we had panel overlapping panel. Using this approach ensures optimal aluminum panel fitment and alignment. Be sure to thoroughly mark these aluminum panels prior to removal and drill the panels that overlap. Take numerous photos also, so you can put this king-size jigsaw puzzle back together.
Project 3: IFS Installation Preparation
Step 1: Install F Panels
Before installing the car’s IFS, install the engine bay’s F panels. Specifically, mark, remove, and silicone the back side of the panels where they meet with the frame, put back into place, clamp, drill, and rivet the panels into their permanent home in the engine bay. If you’re not building an FFR, you probably don’t have these panels.
Step 2: Inspect Components
The IFS consists of the following: upper control arms, lower control arms, ball joints, Zerk fittings, and fasteners. Tools used include: a vise on a workbench, 13/16-inch socket, 5/16-inch wrench, 15/16-inch wrench, torque wrench, thread locker, 3/8-inch wrench, 3/4-inch socket, ratchet, and white lithium grease.
Step 3: Install Grease Fittings on Control Arms
Each lower control arm has two Zerk (grease) fittings. Use a wrench to torque them as shown, but be careful not to overtighten and strip them. In the case of an FFR Mk4, use a 5/16-inch wrench. Here’s a helpful tip: Dab your finger into the white lithium grease and spread it around the end of the neoprene/steel sleeve ends in the lower control arms before installation. The extra lube helps eliminate suspension squeaks. It may make the sleeves easier to install.
Step 4: Tighten Lower Control Arm
After using lithium grease on the neoprene/steel sleeves, install the lower control arms. While holding the control arm parallel to the ground, torque the lower control arms to the specified torque setting indicated in your assembly manual. FFR’s Mk4 lower control arm bolts are torqued to 100 to 110 ft-lbs. We used our shop stool and a box to hold the control arm parallel to the ground while torquing. I also held the box-end wrench while Dad applied force to the torque wrench. To accept OEM arms, the rear bushing mount is wider. Use the large shim washers to take up the additional space.
Step 5: Prepare to Assemble Upper Control Arm
For assembling and installing the adjustable upper control arms, you need ball joints, ball joint boots or sleeves, upper control arms, fasteners, thread locker, a vise, 3/8- and 3/4-inch wrenches, a 3/4- inch socket, and a torque wrench.
Step 6: Install Upper Control Arms
After applying blue thread locker to the upper ball joint threads, place the ball joint in a bench vice, grab the upper control arm, and tighten it. Then use a 3/8-inch wrench to screw the Zerk grease fittings into the ball joints.
Step 7: Install Upper Control Arms
Using the two vertical-mount holes on the 2 x 3-inch tube, install the upper control arms to the chassis. Torque the bolts to 100 to 110 ft-lbs. The arms simply slide into the chassis brackets.
Independent Front Suspension
This is where the fun begins!
Front Shock Absorbers
Factory Five Racing includes some pretty phenomenal shock absorbers in the Mk4 Complete Kit. Koni coil-overs have won many races on sports cars and racing machines all around the world. But before you can install the Konis on your front suspension, you need to assemble the coil-over springs onto the shock bodies.
This is where a high-quality pair of snap-ring pliers comes in handy. If you don’t have a pair, borrow one from a local machine shop, or perhaps rent a pair from an auto parts retailer.
Project 4: Front Shock Absorber Installation
Step 1: Prepare to Install Shock Absorbers
To assemble and install the front Koni coil-over shock absorbers, use the following tools and components: snap-ring pliers, 3/4-inch wrench, 3/4-inch socket, ratchet, torque wrench, Koni front shock set, IFS components, and insulated clip hardware.
Step 2: Install Coil-Over Sleeve on Shock Body
Place some white lithium grease on the shock bump stop before sliding the coil-over sleeve over and past the bump stop. Screw the spring seat on the coil-over sleeve, making it closer to the unthreaded end of the sleeve. Be sure to slide on the unthreaded end of the sleeve first, so that it sits on the snap ring on the shock body. Remove the snap ring from the coil-over hats with a snap-ring pliers. Slide the rubber bump stop approximately 2 inches down on the shock shaft. Place the spring and hat on the shock and rotate the spring seat up the sleeve to make sure the spring pushes the hat tight against the end of the shock. Make sure the slot in the snap ring and the opening in the spring hat are not aligned, and then install the snap ring on the spring hat. (The FFR Mk4 Complete Kit assembly manual provides detailed photos of this operation.)
Step 3: Install Shock on Control Arm
Pass the shock body through the upper control arm with the shock body facing up, and hang the shock by temporarily running a long Philips screwdriver through its upper attachment holes. Do this to attach the .43-inch shock spacers that are supplied for the lower control arm in the FFR Mk4 Complete Kit.
Step 4: Attach Zip-Ties to Spring Hat
After making sure that the spring is properly seated on the shock, run zip-ties through the holes in the spring hat and around the spring to prevent the spring from becoming unseated.
Step 5: Measure Shock Spacers
The FFR .43-inch shock-tolower-control-arm spacers are a bit oversize; they measure .438 inch on the micrometer. This means that you need to use a flat file to make the spacers the correct size to fit on either side of the lower shock end and within the lower control arm mount.
Step 6: Torque Bolts on Shock Absorbers
After filing the lower .43-inch spacers to the correct size and installing the lowercontrol-arm-toshock fasteners, install the supplied .675- inch top mount spacers and the top mount bolts, washers, and locknuts. Torque the upper and lower shock-to-control-arm fasteners to 40 ft-lbs with a Craftsman digital torque wrench. Torque the bolts to the specifications recommended for your manufacturer’s kit. (The FFR Mk4 Complete Kit assembly manual has a frontsuspension torque specs chart.)
The front spindles are very well constructed and are powdercoated black. Installing them to the upper and lower control arms is easy. What’s a bit more of a challenge is installing the front hub assembly on the spindles. It’s a very tight fit. The fitment of your spindles to hubs may be looser than ours. If so, you’re lucky. If not, you need to evenly sand/hone the spindles, which eventually enables you to place the hub assemblies on the spindles. As with everything regarding the building of your Cobra replica, use care in sanding the spindles, so that they remain round.
Project 5: Front Spindle Installation
Step 1: Assemble Front Spindles
Front hubs and spindles, steering arms, IFS components, a 13/16-inch socket, torque wrench, needle nose pliers, and a rubber mallet are all used in assembling the front spindles, hubs, and steering arms. See those bent steering arms? We discovered that FFR mistakenly shipped us the steering arms for an FFR 1933 hot rod. Everyone makes mistakes. After we notified FFR that the steering arms were for a different kit, the correct arms arrived the next day. They included the shipping labels and paid for the return shipping to get the 1933 steering arms back to them.
Step 2: Torque Castle Nut
After using the supplied fasteners and torquing the castle nut on the ball joint, we realized we needed to use more spacers to properly install the cotter pins. We purchased two grade-8 spacers for each side from the local hardware store and fit those beneath the castle nut and above the supplied spacer. You may not need additional spacers. With all in place, torque the castle nut to 80 to 110 ft-lbs. To prevent the spindle from rotating while torquing the castle nut, you can wedge a rag-wrapped 2- x 4-inch piece of wood between the chassis and the spindle. The blue ball-joint boot goes on the bottom. Repeat this same process with the top castle nut and cotter pin, making sure that you install the black ball-joint boot before fastening the castle nut, torquing it to 95 ftlbs, and installing the cotter pin.
Step 3: Install Cotter Pin in Castle Nut
With everything aligned properly, hammer and spread open the cotter pin, thus locking the castle nut into a secure and safe position. A flashlight helps to find the hole for the cotter pin.
Step 4: Inspect Front Suspension
With the work completed, take a step back and admire your work. Also inspect the front suspension installation to make sure your work here is correct.
Step 5: Torque Steering Arm
Upon receiving the correct steering arms from FFR, torque them to the specified 60 ft-lbs.
Step 6: Torque Hub Nut
After evenly sliding the front hub into place, use the large 36-mm socket to torque the hub nut to 225 to 250 ft-lbs of torque. With such a high torquing force, you can secure a drum and piece of 2 x 4-inch wood underneath the spindle to keep the entire front end steady. Be sure to install the hub dust covers before moving to the next step.
Front Disc Brakes
The final component to any front suspension system has to be a good set of disc brakes. Spending the bucks on building a top-notch Cobra replica doesn’t stop here. But if the disc braking system is top quality, as it is with FFR’s Mk4 Complete Kit, the car most definitely stops straight, swift, and true.
By the way, FFR, in partnership with Wilwood Brakes, now offers optional larger four-piston-caliper front disc brakes.
Project 6: Front Disc Brake Installation
Step 1: Inspect Components
The front disc-brake assembly consists of the 11-inch rotors, two-piston calipers, brake pads, fasteners, flex lines (in a large plastic Ziploc bag), torque wrench, 16-mm wrench, 12-mm socket, ratchet, and thread locker.
Step 2: Install Caliper Slider Pins
First install the caliper slider pins on the caliper by using a 16-mm wrench, a 12-mm socket, the ratchet, and the supplied bolts. Hold the retaining nut with a 16-mm wrench and torque the bolt head at the front of the caliper.
Step 3: Torque Caliper Slider Pins
After you have snugged up the slider pins, verify that they have been properly torqued. Make sure to torque the caliper slider pin bolts to 25 ft-lbs. Use a 16-mm wrench to firmly hold the pin while you use the other hand to torque the bolt. Anywhere in the range of 23 to 26 ft-lbs should be fine. Also install the supplied slider grease boots on the slider pins (per FFR manual photo).
Step 4: Install Steel Clips
On the ends of the caliper hangers, place the steel clips from the hardware bag. Press them (by hand) into place on the cast hangers. There are four clips that go on the ends of the hanger that must be installed with the long tab facing out, as shown here. The two remaining caliper clips go in the center of each caliper. Locate the long tab where the caliper pistons are and the short tab on the other side.
Step 5: Install Caliper Clip
Viewing the center caliper clip from the outside of the caliper offers another perspective on how the clip is installed correctly.
Step 6: Lubricate Caliper Slide Pins
To ensure proper function of the front brake calipers, use the supplied silicone grease on the caliper slider pins.
Step 7: Install Caliper Hangers
Use your hand to slide the caliper hanger onto the caliper.
Step 8: Slide Rubber Boots over Slider Bolts
Together, the caliper and caliper hanger look like this. Push the rubber boots over the lip on the caliper bracket to properly seal the slider bolts.
Step 9: Install Brake Pads
After assembling the caliper and caliper hangers, install the brake pads. Look at the backside of the brake pads to differentiate the inside pads from the outside pads. The studs on the inside pads are out near the ends of the pad. The studs on the outside pads are close to the middle.
Step 10: Clean Brake Rotors
Before pushing the brake rotors onto the hubs, clean them thoroughly with brake cleaner.
Step 11: Torque Caliper Bolts
With the rotors on the hubs, mount the caliper on the spindle. The brake fluid bleeder must be at the top of the caliper. Torque the caliper mounting bolts to the specified 95 ft-lbs.
Written by D. Brian Smith and Posted with Permission of CarTechBooks