Grounding Block Behind Dash

I added an additional terminal block behind the panel for grounding various items. It’s grounded locally through the jumper wire down to the 2″x2″ chassis member.

I had to remove the brake biasing knob to install the rivnut for the grounding wire.

While I had the knob out, I installed a couple of 8-32 rivnuts and used some of the torx-drive screws. I had previously used some sheet metal screws, but I’m trying to eliminate all of them.

Wiring Connectors and Rear Brake Line

My order of Weather Pack connectors showed up, so I installed the remaining ones that were missing. For the headlights, I also fabricated short jumper cables to the plug that attaches to the back of the bulb. When I switch to LED bulbs, they might have a different connector on the back, so it will be trivial to fabricate a different jumper if necessary.

I also got started on the rear brake line. This line runs from the forward side of the pilot’s footbox, along the upper 3/4″ tubing to the x-frame and down to the main 4″ chassis tubing. There will be a union there to the piece of tubing that runs the rest of the way to the rear tee.

Chassis Rivnuts & Front End Wiring

I knocked out a bunch more of the chassis rivnuts that will secure the aluminum panels. Unfortunately, the 8-32 mandrel broke after a couple hundred, so I had to stop. Astro Pneumatic has a 1 year warranty and claims they will replace any component that fails under normal use, so we’ll see if they cover this. In the mean time, I have plenty of other things to work on.

Three of the wires in the front chassis wiring harness (parking lights, low beams and high beams) need to be split and run to both the front left corner and front right corner. I stripped the insulation and used a few solder sleeves to splice into the wires. The bundle for the front left corner (which also includes the left turn signal) cuts under the chassis tubing and runs across the top edge of the radiator, secured by some adel clamps.

I ran out of three-conductor Weather Pack connectors, so I just terminated these with the appropriate plugs and seals. There will be two connectors here: one connector for the headlights with a ground wire, low and high beam wires, and another connector for the indicator light with a ground wire, parking light, and right turn signal.

Another pair of wires drop down to the lower chassis tubing for the fan wiring. There will be a rivnut and zip-tie mounting block installed here, but it’s just zip-tied for now.

From there, it runs across to the fan. There will be a couple more attachment points across the lower edge of the fan shroud to secure this cable.

The cable that cuts across the top of the radiator runs down the left chassis member and terminates in a similar set of six wires. The two ground wires are secured to the chassis with a screw behind the bundle of four terminals to the left.

Taillight Wiring and Clutch Pedal Clearance

I installed Weather Pack connectors on several of the tail lights. I ran out of three-conductor connectors though, so I couldn’t finish all of them.

I also installed the female connectors on the chassis on both sides. These are electrically identical and all lights have identical connectors. This is possible because the InfinityBox lets you use the same lights for brakes and turn signals. Although this is possible with a combination of relays in a traditional wiring harness, most builders don’t wire it this way. They end up using the dim filaments in all four tail lights for their parking lights, but the bright filaments in one pair of lights for the brakes and in the other pair of lights for the turn signals. In our car, all four bright filaments will be used for brakes and turn signals.

When I moved the pedal box up, it caused interference with the 3/4″ tubing that cuts through the middle part of the driver footbox. There must have been some stress in this tubing because the two pieces shifted out of alignment with each other when cut apart. I’ll weld in a new piece of 3/4″ tubing on the outside of this tubing. I’ll try and realign the pieces of tubing when welding.

It took a few extra trims on the forward end of the tubing to allow the pedal to go all the way to the front of the footbox, but I now have full clutch travel.

Horn and Taillight Wiring

I cut back the sleeving on the wiring harness to the front right of the car and put a terminating piece of heat shrink on it to keep it from unraveling. I then cut the horn wire and created a jumper between the horns.

I also installed a grounding point on the forward 3/4″ tubing and grounded the horn there. The lights and fan will also ground here.

The ground wire also jumpers between the two horns.

I also added a grounding point on the left side diagonal chassis member to ground the rear load cell.

I figured out which wires will be routed to the rear lights and put some expandable sleeving over them. I’m routing them over the top of the fuel tank.

I used a solder sleeve to tee the parking light wire and then dropped the wires down behind the tank near the center.

Wiring Harness and Horns

I slipped some expandable sleeving over the bundle of wires going to the front of the car and secured the harness to the firewall to the left of the load cell.

The harness routes under the upper chassis tube and is secured to the outside.

The harness will split at the top of the radiator and route to the various loads at the front of the car: lights, fan, and horn. I went ahead and installed the horns along the upper tubing beside the radiator.

Spliced Into Front Load Wires

I used some solder sleeves to splice the fusible links into the six wires on the front load cell that need to be indicated on the dash.

I put an extra piece of heat shrink over the solder sleeve to protect them.

I also added a rivnut to the side chassis tubing to  ground the front load cell.

Fabricated Fusible Links

For the dash buttons and indicators, I’m tapping off the power wires on the load cells and running some 22AWG wire  back to the dash. The power wires on the load cells are all 14AWG though and will use various size fuses (many of which will be too large to protect a 22AWG wire). I need to provide protection for these small wire in case they short to ground. Without separate protection for these wires, they could get hot enough to burn before blowing the fuse in the power cell. I could of course use a bunch of inline fuses, but a more reliable and compact way is to use fusible links. A fusible link is nothing more than a short section of smaller wire that will melt before the larger wire can get hot. Like a fuse, this section of smaller wire needs to be enclosed to prevent the melting wire from catching something nearby on fire.

The general rule is to use a section of wire 4 wire gauges smaller than the wire you want to protect. Since I’m using all 22AWG wires from the load cells to the dash, I spliced in a short section of 26AWG wire.

I slipped a section of silicone impregnated fiberglass sleeve over the 26AWG wire. This won’t burn and will contain the heat if the fusible link ever melts.

To keep everything together and limit flexing of the 26AWG wire, I slipped a section of heat shrink over the whole thing.

I fabricated six of these for the loads at the front of the car that I will tap into: headlights (low and high beams), parking lights, turn signals (left and right), and fan.

Electric and Final Fuel Lines

Jenn and I hooked up a number of the circuits connected to the battery and ignition terminal blocks. The rightmost wire in each terminal block is the feed line. The battery terminal block is wired to the starter terminal with a fairly heavy 10AWG wire with inline 30A fuse. The remaining terminals all have smaller inline fuses protecting the wires connecting them to each battery load.

The ignition terminal block is wired to the ignition output on the front load cell. There are still a couple of additional wires to connect to these terminal blocks, but this is enough to get the gauges working and engine running.

Jenn and I wrapped up the starter wiring with the 30A inline fuse. Normally, the battery feed would be connected directly to the battery to minimize voltage drop during engine cranking, but that is minimal with a 2/0 wire to the starter. I also installed a rivnut to secure the wires to the chassis near the bellhousing.

I installed fuel line armor on both the supply and return fuel lines. This is basically just a stainless steel spring that surrounds the tubing to protect against road debris.

I also fabricated the forward fuel lines that come up through the hole in the floor. It looks like the line is touching the edge of the hole, but that’s just the armor. I may still relieve this a little more when the car comes apart for final assembly.

The lines come up just inside the passenger foot box. I then fabricated the final hoses that connect the fuel lines to the throttle body.

Before firing the engine again, I undid the two fuel fittings at the throttle body and connected them together. I run the fuel pump for a minute or so to flush any debris out of the lines. There shouldn’t have been much since I blew out all of the lines and hoses with compressed air, but I’d rather have any small particles end up back in the fuel tank (upstream of two fuel filters) rather than stuck in the throttle body.

After a final check, we restarted the engine for the first time in about four months. It looks like all of the systems are working well together.

Installed Ignition and Battery Terminal Blocks

There are a number of circuits that need direct battery connections (inRESERVE button, FiTech EFI, clock, GPS keep-alive in the speedometer, and inDASH MAX). There are also a handful of circuits that need power only when the ignition is turned on (electric power steering, FiTech EFI, and voltage gauge). I installed these terminal blocks on top of the 2″x2″ chassis member behind the dash.