Wiring harness tips and info please?

767Jockey · #1 (**permalink**) 04-05-2008, 11:15 PM

I'm restoring an old Contemporary Cobra. I'm at the point where the body is about to come off. I really only now got to get a good look at the wiring harness that's in there, and I'm less than pleased with it's condition. It's old, full of splices, etc. I'm thinking that since it's not a real huge expense, and the car is completely apart already, I might as well put in a new one. Anyone replace a harness lately? I'm thinking right now about Ron Francis or Painless. Any pro's or cons on either? Anyone else out there make something better? I can't tell for sure but I believe that the turn signal switch in the car is a VW unit. I'm most concerned about this as both websites show no compatibility with this turn signal switch control. I'm not sure how I would figure out which wire is which on the turn signal and how to adapt it to the harness. If it helps, here's the harness info I sent to the two companies:

-Car is Contemporary Cobra replica.
-427 FE engine with Carburetor
-MSD distributor with MSD 6AL box
-Main radiator electric puller fan (Spal high capacity single fan)
-Two pusher electric fans in front of radiator.
-I want fans to turn on and off automatically, with ability to turn on and off manually as well (need appropriate relay system)
-electric windshield wipers
-electric fuel pump (need relay system for pump)
-Volkswagon turn signal switch assembly
-60 amp 3 wire Ford alternator with external regulator
-electric fuel gauge
-rear license plate light
-no heater, air conditioning, radiator
-ammeter, not voltmeter
-I’d like everything to integrate seamlessly

Can anyone think of anything I missed, and anything I can be doing differently? I'm not real strong electrically, so having a clean sheet of paper may very well be the best way for me to proceed with this. Any and all input is greatly appreciated. Thanks!

strictlypersonl · #2 (**permalink**) 04-06-2008, 04:52 AM

The turn signal switch wiring is very conventional. I'm sure it will work with either harness.

The problem will lie with the brake/signal system. Do you have relay F as shown in this picture?

mickmate · #3 (**permalink**) 04-06-2008, 06:31 AM

Separate, tail, stop, directional lights?
Two speed wipers? (Slow and really slow)

767Jockey · #4 (**permalink**) 04-06-2008, 11:56 AM

Quote:

Originally Posted by strictlypersonl

The turn signal switch wiring is very conventional. I'm sure it will work with either harness.

The problem will lie with the brake/signal system. Do you have relay F as shown in this picture?

I don't recognize that "F" relay. My wiring is so sloppy and such a mess it could be hiding anywhere, but I don't recall seeing one of them. What is it, what does it do, and what are the ramifications of having one vs. not having one?
Thanks!

767Jockey · #5 (**permalink**) 04-06-2008, 11:58 AM

Quote:

Originally Posted by mickmate

Separate, tail, stop, directional lights?
Two speed wipers? (Slow and really slow)

Nick,
I never used the wipers before I tore the car down - I have no idea if they're single or dual speed. As far as tail bulbs, there's only one bulb in each taillight assembly. Each single bulb serves as taillight, brake light and turn signal. Ideas? What would you do?

strictlypersonl · #6 (**permalink**) 04-06-2008, 04:44 PM

The F relay above allows the brake and signal light function on each side to be shared by a single filament. It's also possible by using a trailer relay, but since this was an early Contemporary, I figured that they would have used an original relay. On the other hand, the original builder might have gotten creative.

767Jockey · #7 (**permalink**) 04-06-2008, 04:58 PM

Hmmmmm.....Do these things usually get accounted for in a new harness or am I going to be on my own to adapt something that works? Has anyone put a new Painless or Ron Francis harness in? How was this situation handled? Thanks for all the great info, SP.
Doug

computerworks · #8 (**permalink**) 04-06-2008, 05:05 PM

You may want to check with Kirkham...I believe they have converted old-style to a Painless-based system.

If you have it, the Lucas "big-silver-box" relay (DB10) is usually mounted on the firewall.

767Jockey · #9 (**permalink**) 04-06-2008, 07:07 PM

Thanks Ron - I definitely don't have one of them. I wonder what they used? I have a small black box about 1" square that I can't identify with a plug going into it - it sort of looks like a plastic flasher can, but I know it's not the flasher as I found that too.

tcrist · #10 (**permalink**) 04-06-2008, 08:49 PM

Another wireing company is " American Autowire". You can find them on the WEB. There harness is designed around GM but if you call them they will help you out. If you can get a wireing diagram for the VW unit they will tell you what wire to hook up where. The wires actually say where they go to, not just number matching to numbers on a diagram. I think Painless does the same.

Terry

cobrajam · #11 (**permalink**) 04-06-2008, 09:54 PM

On my previous Cobra I used a Ron Francis. It worked out nicely. I would give them a call and let them know the particulars. And the few times I ran into a snag they were good about offering support. I may end up going that route, if I can sell the harness I already have. Got a box full of labeled wires and a fuse box, but no instructions.

tcrist · #12 (**permalink**) 04-06-2008, 10:51 PM

The American Autowire kit comes with a colored diagram with everything labeled. I know that you can get them in 15 & 22 (I think) circut kits.

Terry

mickmate · #13 (**permalink**) 04-07-2008, 03:52 AM

Hey Doug how about a wiring harness made for your car you could pretty much lay in place?
http://www.britishwiring.com/Ac.PDF

berzerko · #14 (**permalink**) 04-07-2008, 05:22 AM

the harness from haywire thatcame with my kit was pretty much idiot proof every single wire was marked every 6"

http://haywireinc.com/catalog/index....eugap074q5l4j2