Building a Wiring Harness

[ronzara]

I was curious. Has anyone built their own wiring harness for their Cobra? Seems to me like it souldn't be that difficult. I would appreciate any advice on this matter. If someone has a diagram of one they've made, I would be greatful. I am trying to save $$$ and this seems like a spot that can cut costs in a big way. Thanks.
RZ

[kountzecobra]

I have never built one, but I had to completely strip mine and add and remove circuits to suit my particular application. I don't think you can build a complete harness for what a Painless Wiring harness with fuse block costs. One problem with building your own is the lack of different color wire insulation to distinguish one circuit from another. (Standard building wire is not acceptable, as it is not flexible enough.) A complete 12 circuit wiring harness with fuse block is only about $260 from Summit Racing. Wiring is not a place to scrimp and save a few bucks- an electrical fire can completely destroy a fiberglass car. Hope this helps, David Shelton.

[carlo]

Ron HelloAgain, I built mine completely from scratch, Used a GM fuse box out of a buick sommerset and the steering column, there is a lot of thinking(time) involved with these, but it is do able, it helps if you have an electrical background.Other than that you may be better off with that summit deal, for 260$

[Dan Heck]

Ron-

I built my own wiring harness for a previous project- a 350 chevy powered 1940 Ford coupe street rod with a TH 350 auto trans. It wasn't that difficult, but was rather time-consuming. I made my own fuse panel and used a combination of clean junkyard and new aftermarket connectors and the like. Doing it all the way yourself enables you to use heavier-duty wiring where you think you need it, and my finished system was always 100% reliable in every respect. I used the book 'How to do Electrical Systems' by Skip Readio from Tex Smith books [I may have the title slightly wrong]- it has chapter-by-chapter instructions for each of the major systems and a complete wiring diagram. The book's system is based on the GM steering column harness layout and GM headlight switch due to the popularity of the small block chevy in street rodding circles. There is some info on the Ford and Mopar wiring conventions as well-they're quite similar. The vast majority of the content is generically applicable to any project. I had no particular electrical expertise beforehand & mine came out fine so I would recommend this book to an amateur wanting to give it a try. I would think that a typical cobra system would be even easier due to the lack of optional accessories, but this might be balanced by the need for more ground wiring on the fiberglass body.

Dan

[Rick Yeager]

Ron,

I wired mine essentially from scratch. It is the second kit car that I have wired and like Dan, have not had any special electrical experience. It does take some thinking and planning. For me the hardest part is the turn signal, emergency flasher and stop light circuts. I used a Mustang II column in my kit so I retained the flasher system from it and wired from there. The Mustang switch had the advantage of being able to be wired with the brake lights on the same circut as the turn signals or on separate circuts i.e. for the two rectangular or four circular tail lights on a Cobra. I did not use the column ignition switch but ground the key opening area flat and filled it in with putty. After market in dash ignition switches can easily and affordably be obtained from parts stores and catalogs as well as fuse blocks. Since I was using the Ford turn signals I tried to stay with the Ford wiring colors as much as possible so if somebody else had to work on it, they would not be lost or scared off.

The biggest problem I have found is that by using after market dash switches I have not found a clean way to ground my windshield wiper motor so that it will automatically go back to park.

I used the older ('74) Ford alternator with a late 60's early 70's Chrysler regulator and also used a Chrysler ignition module which wired easily into the Ford Dura Spark electronic distributor. They seemed simpler to use than the Ford.

The Ford solenoid had the two small posts rather than the one so that a second solenoid was not needed.

Also you might find wiring a volt meter in easier than an amp meter.

Be sure and keep good notes and diagrams of what you have done.

Like Dan, I would really warn you to make sure your grounds are good. Somewhere I read that ground problems are 85% of car electrical problems and it has certianly been true for me.

I also used heavier wires in many places. You would probably be better off with a kit but if you are interested in doing it, go for it--it can be done and done a little more affordably if you shop around. I learned a lot by doing it myself and all in all it was fun.

Please let me know if I can help any more.

Rick

[Wade Chamberlain]

Rick - I made a wiring diagram of a setup that will allow your wipers to self-park using a simple DPDT (center-off) switch and two relays. Email me if you'd like it.

[carlo]

ron,i also used the same book mr.heck used, very helpful,it also helps if you have a continuity tester.

[Jim Downard]

I have a complete Classic Roadsters wiring harness for a Ford engine still in the box. All you would have to do is cut the hole for the fuse block to mount in. I'd consider selling it, but I currently use it to trace any kind of electrical problem I might have, as the CR book is not very informative as far as a diagram goes.

Jim Downard

[427sharpe]

i did mine completely from scaratch, because I wanted an exact fit. found oe type connectors at a warehouse supply in Dallas and ordered color coded (striped, dashed, etc..) wire from Del City Wire. Very clean, and it fit precisely as I wanted it to, with no extra circuits or junkyard parts. Has held up very well for many years..the only weak point were the oe Lucas switches, which have been replaced with lookalikes that are not only much cheaper, but have held up much better!

[Bob Putnam]

Sharpe,

And how much money did you spend to make your harness? We seem to have lost the intent of RZ - to save money.

Wire ain't cheap. The only way to minimize cost is to use only a few colors and gages. To make our harnesses, I use 55 different rolls...

$250 for a ready-made harness is cheap, even if you don't value your time.

[Dan Heck]

Bob has a point there about the wire costs- I neglected to mention that I had fallen into a good deal on some closeout automotive wire for my prior wiring harness project. The good automotive wire has finer strands than the household-type wiring of the same gauge. It's more flexible when you try to run a 1" bundle of wire around a tight corner. I recently found vast quantities of extremely high quality wire at the local alloy & nonferrous metals scrap dealer. Apparently surplus from some sort of wiring project or other- very good stuff in assorted colors/sizes from 8-16 gauge, with hi-temp insulation. Some was still on half-filled spools. [Must've been a government project to be so wasteful]. I think that a big assortment-sufficient to do an entire car- was maybe $20. To the dealer it's just copper. However, after doing it myself the first time, in my current cobra project I decided to go with a harness kit just to save time and trouble.

Dan

[Steve R]

Sharpe,
could you e-mail me with the name and phone # of the place you got the connectors from?
Thanks,
Steven