Project Civic Racecar Waits for Tech Inspection

Project EF Civic Racecar: Witchcraft & Wizardry

The wires that go from the ignition switch to the ECU and starter relay. The starter signal wire has been cut and bridged with incorrect spade terminals.
Under the dashboard, we found the main power from the key to the ECU and distributor. The black/yellow wire here powers the EFI system, so if we wire it to the master switch, it will shut down the ignition system, the ECU, and the fuel pump, completely killing the car. Looks like we were not the first shade tree mechanic to poke around here. Someone previously cut the black/white wire (which is the starter signal) and then used two female spade connectors to fix it.
Starter and EFI wiring tucked back into the factory sheathing with the extensions added for the kill switch
We removed the spade terminals and spliced the starter wire back together. We then cut and spliced in some extension wires for the main power wire to run them under the dash to the master switch. We were able to tuck the wires back into the factory sheathing for protection.
Looking at the alternator dump circuit. The wire has a bulk resistor spliced into it and grounded to one of the ECU mounting studs.
The last step was to wire up the alternator discharge circuit. If power is cut by the master switch, the alternator loses its discharge point. Electrically, this is similar to shutting the throttle of a turbocharged car with no BOV. The battery acts as a bulk resistor to let the alternator discharge when the engine is shut off. Turn off the car without allowing the alternator to drain, and you can hurt the alternator. The Pyrotect switch has an extra circuit that activates when the switch is flipped to allow the alternator to discharge into a bulk resistor that Pyrotect provides. We wired this in to keep our new alternator happy. The circuit connects to the charge side of the master switch and dumps into a ground with the bulk resistor added. We decided to ground ours to one of the ECU studs. We also removed the ECU cover panel for some free weight savings. This car will never have a passenger again, so we don’t really need a kick panel on our ECU.
The old ground strap with dried out insulation and corroded wire and terminal ends
The last little electrical repair project is the engine to chassis ground. Our ground strap was getting brittle and corroded from 30 years of service. The insulation was beginning to crack and flake off. A broken ground strap is a silly and easily preventable DNF.
New ground strap installed on the engine and chassis.
We decided to use some of the leftover pieces of wire from the kill switch and alternator to replace the engine to chassis ground strap. All we needed to do was cut the cable to length and crimp on the appropriate ring terminals. Much better.

With our electrical system working again, we ran a few more autocrosses with the car and faced zero issues.  With a fully functioning car, we can now turn our attention to modernizing and upgrading the suspension, brakes, interior, and cooling system.  We’ll be back with more Civic action soon!

Sources

Braille Batteries

Tire Rack

NAPA Auto Parts

Pyrotect

More Civic Racecar

Part 1: Redheaded Stepchild 

Part 2: Dusting Off The Cobwebs

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