70 ghia wiring

[dragboat]

hi guys . have a 70 ghia shell that i'm doing . my question is on the VW service manual wiring diagram . what are the #s on the wires ? are they the size of the the wire that should be used ? if so , what is it in . i know its not AWG . is it in MM , or in. or what .the only wires existing in this car , are the ones hanging out of the steering column . so i have to make up a complete wire harness . i'm planning on a complete subaru drivetrain swap using there M6 trams .

[jeffrey8164]

They are metric in mm.
When I made mine I used 14ga for pretty much everything except the hot feeds from the battery and from the ignition switch to the starter. For those I used 10 gauge.
The stereo is a whole different beast.
I semi envy your Subi swap. I contemplated it along my Ghia journey but decided I didn’t want to modify the body of the car. If/when I sell it, the new owner can go back to stock easily.
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[dragboat]

thank you for the input . mow i have to sit my but down and do some serious drawings to come up with a workable harness .

[54bug]

Hi Dragboat

Welcome to the world of rewiring. There are way to many ways to start and finish the project. I built a harness for my 1969 bug. Took a while, but worked out well. My process and thoughts follow.

If the factory harness is present and mostly functional it's a great starting point. The DIN Standard spec was used by VW and is really helpful. Looking at the Factory wiring diagram you can see the colors and the DIN numbers on the most wires. Ground is always brown and numbered 31, Hot from the battery is Red and numbered 30, Switched hot is Black and numbered 15. The Bentley manual has a great diagram and a list of numbers. A great place to get an overview. I used the factory harness wires to feed Exterior lighting, brake lights, fuel tank sensor, and wiper wiring.

I added several 12 wire, 12 gauge cables to the system. and built a supply bus between the Alternator, Battery and Fuse box, with breakers protecting everything. there are 2 runs of 12 conductor sheathed from dash to the tail and dash to the back seat. Cable bundles that are basically 12 conductor extension cords are available from Grainger, Graybar, or better electrical supply houses. I used 8 gauge cable for the main harness, and bought a spare beetle harness at a swap meet to get the colors I needed. A bunch of terminal strips, and VW connectors ( Swap meets or classifieds are great) https://www.thesamba.com/vw/classifieds/detail.php?id=2460293

I planned my harness using an Excel spread sheet. I used the new cable bundle from the engine to the dash for the engine controls. the bundle from the dash to the back seat for stereo, accessories. the original harness was used for lighting, Etc. By Laying out terminal strips at major junction points I could plan the structure.

I added 3 new panels to the car. one for stereo/Amp on the passenger side inner fender, One for Relays on the Drivers side inner fender, and one on the drivers side under the back seat for major breakers and accessories. You will need to figure out where you want the battery mounted. It fits well in a battery box under the rear window, or under the rear seat. I preferred it out of the engine compartment.

Define all the gauges, relays, accessories, stereo gear you will need. What dash switches you will use (Intermittent Wiper switch with electric washer) Plan all the gauges on the dash, radio head unit(in the glove box and amplifier placement (in the glove box), amplifiers, powered blue tooth, phone adapters. Plan your interior and trunk, engine lighting plan including 3rd brake lights. Lay out your speakers in the car. I ended up with many relays starting with Ignition, security, headlights, driving lights, fuel pump, brake light, horn, head unit, amplifier.... It's a list with locations.

I found the Porsche 911 and 911 gauges were perfect and the VDO cockpit small gauges matched. I over built the stereo, not thinking how loud the car world be. I'm really happy listening to it while parked, but the car is too lound to practically listen at highway speed.

Lay out terminal strips at major junction points in the car. 2 engine compartment 4 behind the dash, 16 fuse distribution box, one or two at each panel. The 8 gauge main bus connected the alternator battery and feed to the dash using breakers and Painless performance terminals protecting Alternator, battery, fuse box, and stereo feed.

Make the panels and mount the terminal strips and run the new cable bundles. Stereo on the passenger side, Engine on the drivers. Leave plenty of cable at each end. I was able to follow the stock harness on the Drivers side, and make the passenger side harness look similar.

Start the spread sheet Each terminal strip is a section of your spreadsheet. Use the Din numbers and colors to reuse the stock harness. Allocate the wires by color or number through each of the terminal strips front to rear and get that into the spread sheet. Do the engine bundle next, tail to nose one terminal strip at a time. all the gauges, fuses, and terminations by color in bundle. Do the accessories, stereo, lighting with bundle 2. B1-white/blk is Bundle 1 white with black strip conductor.

The Spread sheet is your wiring map and diagram. Keep it updated as you connect everything. Once it's planned the real work of "wiring" starts. There were changes as I wired the car, and it was updated until complete. The copies in the car are really important as thing break!

Plan out each sub panel. where the relays go, grounds etc. I used Painless products relay mounts, as they were clean mounts and allowed replacement of bad relays. layout the relays, and router wires to terminal strips on each panel. Plan out the main buss cables. I mounted a battery minder to the under seat panel with a plug in the engine compartment to keep the batter when parked.

I built and tested each panel in my shop, using a model train transformer and some test lights. The assembled panels were mounted with DZUS fasteners, for repairs and changes. Keep in mind you will be fixing it at some time.

After mounting the panels, fuse box and terminal strips. I followed the spreadsheet to connect the wires from each end point through the terminal strips. I labeled the wires with Ink pen on stick labels at each junction.

Lots of work, but the results have been great. Started, drove, the first time with all the sensors and lights. As a software engineer I've found how much planing is needed at work and on cars. easier to do it right once, than try to chase down errors.

As a disclaimer, everyone has a different set of goals. I don't know what you want, but I could define my list. I couldn't afford to have this work done. A friend who was a mechanic trainer for VW has high praise for the work, but laughs and reminds me that: "No one judging a car will know what this is".

I found the book Automotive Wiring and Electrical Systems (SA209) really helpful. https://www.amazon.com/Automotive-Wiring-Electrica...&psc=1


Hope that helps. Good luck with your project, Scott

[jeffrey8164]

[dragboat]

hi
i'm wondering where i can find simple items , like plugs for headlights etc. . theres no harness in this car so i guess t's design as you go . i have seen to many cars with the rats nest under the hood , and don't want that . besides a stock harness wouldn't be useable for me . putting in a suburu engine and 6 speed manual trans . the engine compartment wouldn't to hold the battery . i plan on putting the battery in the right side of where the rear seat would be , at its a useless seat anyway . where the bottom of the seat sits , i'll put in a hinged aluminum panel , so i can mount my circuit breakers , 2 fuse blocks , and relay block . i feel it's the only way to keep some semblance of order to keep it looking neat . the back of the seat will become the hinged cover , to protect it . like yourself , i can't afford to have the work done . where the back of the seat is , will become the new firewall . to deaden sound i will be using dynamat pads . for wiring , don't have all those crazy colors you find in a standard wiring harness so i will keep each system a separate color . have a heat shrink tube labeler so each and every wire can be labeled on both end and a termination point # . the wiring schematic i make up will be secured to the underside of the lid . i IRS system apart and am installing a double A arm system with coil over shocks to allow for larger tires for better stability and handing

[54bug]

dragboat

It might be worth starting with a stock harness, and adding bundles of cables to make the job easier. The stock harness will simplify all the basics, including wipers, brake lights, turn signals and emergency flashers. It will connect to all the factory switches, and is designed to flow through the body. It's simplicity makes it an easy starting point, clean installation, and easy to modify.

Clearly the main buss of the car needs to be redesigned. A fuse and relay panel that protect the alternator, battery, and main fuse box isn't all that difficult. A spool of 8 gauge wire. Some protection, and a panel to mount the hardware is needed.

The factory fuse box is easily replaced and the street rod industry provides some great packages. The car needs a ton of relays, lighting, brakes, fuel pump, horn, security, and feeds for the engine systems, and stereo, do not exist. Once you know what you need you need a serviceable location for them. You have a notion of battery placement, that's a great start.

Your engine management plan is clearly going a separate sub harness. I hope you have the factory engine sug harness. One the ECU is mounted you can clean up that sub harness, and lay out your sub harness to integrate it to tie the car and controls into the car. This should be a simple 12 conductor sub harness between the fuses, relays and dash.

I still am a fan of using the factory harness as a starting point to minimize the hard work at the dash and engine ind of the project.

Scott (54 bug)