Electrical System


As with everything on this project, I started with a clean slate when designing the electrical system. There are several companies who supply generic wiring harnesses and components. These systems are made up of pre wired harnesses for virtually all components they make the job a little easier, however I was looking for a sanitary custom job and didnít want a lot of extra unnecessary wire all over the place.

Starting from scratch I designed each major system including the starting system, the charging system, the ignition system the lighting system and accessories


I started building the electrical system by placing the battery in the rear of the car behind the passenger seat, this is a compromise as it is farthest away from the majority of the electrical components but it is out of the way. On this particular project the car is so small, it doesnít really matter much where the battery is located. I built a battery box in the rear floor pan above the differential. The battery only needs to be large enough to supply enough power to the ignition system and starter motor, after that the alternator takes over so I am using a fairly small battery. I grounded the negative battery terminal to the rear chassis and ran the positive cable under the car about five feet to the starter motor using #1 gauge cable, there is virtually no resistance.

The starting system uses a stock GM starter motor. The starter motor case and solenoid case have been chromed (a side note from the bottom of the car, the oil pan, transmission pan, torque converter cover and starter motor have all been chromed, the transmission cooler is polished aluminum so it is pretty bright and very clean underneath). The 1 gauge battery cable offers no resistance and I have not experienced any heat related starting issues that we often hear about with GM starting systems in high performance applications.

Charging System

As with everything else on this project, size and appearance matters. A stock GM Alternator was too big, and wouldnít fit between the chassis and the engine. Because the electrical system consumes less than 30 amps with everything turned on after the car has started, I didnít need a big alternator, so I started looking for one with a small size with an aluminum case that could be polished. I ended up with a 50-amp alternator designed for early Honda civics, it is tiny and happened to look very clean. I bought a rebuilt one from a local auto parts store for just $40.00, polished the aluminum case and added a single grove polished billet aluminum pulley that matched the crank and water pump pulleys, looks clean and fits snugly with custom brackets that I made and had chromed. The compromise is that the Honda unit does not have a built in voltage regulator, so I added a Chrysler electronic unit mounted to the front left fender well.

Lighting System

The turn signal lights on the stock bugeye were separate from the tail lights and headlights, looking at the car from the rear you would see a pair of tail lights and a pair of turn signal lights, pretty standard for an older car. Looking at the car from the front you would see a pair of headlights and a pair of turn signal lights, still common by todayís standards, although over the past few years, more new cars have integrated the turn signal lights into the headlight system. I have eliminated all the separate turn signal lights giving the body a cleaner look and at the same time slightly reducing the amount of wiring. In the rear, I use a two-filament bulb to illuminate the taillights, turn signal lights and break lights. In the front I have replaced the stock sealed beams and separate turn signal lights with a single 7Ē round unit that houses a replaceable halogen headlight bulb and a turn signal bulbs. Thatís right, the headlight flashes amber when I turn on the turn signal just like newer Mercedes Benz. Again, this cleans up the body lines and the wiring, I only need four wires to support high beam, low beam and turn signal on each side. I use a relay to power the headlights so I am able to use small gauge wire from the switch to the relay located at the front of the chassis under the car.

Gauges and Dash

The dash is extremely clean, it includes an ignition switch, five Auto Meter Ultra-lite gauges including a 5Ē 160 MPH inch mechanical speedometer, a 5Ē 10,000 RPM electronic tachometer and three 2 5/8Ē electric gauges for water temperature, Oil Pressure and Fuel level. The dash includes two toggle switches, one for the lights and the other for the turn signals, plus a turn signal indicator light. Wiring comes up through the transmission tunnel and is harnessed so two connectors completely unplug the dash for easy maintenance. This is one of the things that you can not do with a pre-manufactured wiring kit.

Ignition System

I am using a Mallory unilite electronic distributor with a mechanical advance. Unilite uses a photo optic infrared led and supports a low profile cap which is necessary for hood clearance. The distributor is powered by a Mallory promaster coil rated to support 8,000 RPM. Spark travels from the distributor to the spark plugs through a set of 8mm spiral core custom fit wires.

Tips and Tricks

I recommend buying wire designed for high heat applications to use near the engine for water temperature sender, oil pressure sender and alternator it costís more but it is worth it. Everywhere else use high quality automotive multi strand copper wire of the proper gauge. I recommend making use of relays wherever practical, this allows you to use smaller gauge wire from your switch to the relay for a cleaner thinner harness, if your relay is close enough to the source you will not experience resistance. This is particularly important for headlights and electric fans that consume large amperage.

Here is a neat trick, get the power for your headlight, horn and fan relay directly from the alternator. There are several reasons for this, you will save long wire runs back to the fuse box which can experience some resistance depending on length and gauge, your wiring will look cleaner and you will be assured to get maximum voltage off the alternator. Some Old-timers might tell you that this is a bad idea because the voltage coming off the alternator fluctuates and the possibility of power spikes can cause damage. That was true when we used generators, but a properly working charging system using an alternator does not create power spikes! This is well documented and I can tell you first hand it works and works well, but donít forget to put an in line fuse between your relay and the alternator.

Use high quality crimp connectors and buy the best crimping tool you can find, the bargain basement crimping tools donít do a good job and trouble shooting a loose connection after everything is all together is no fun. Donít use solder anywhere, it makes the wire brittle, is subject to corrosion from the outside eliminates and doesnít stand up to vibration.

   © Copyright 2007. kenvoss.com Last update July 2009