Jump to content

After Market (Not stock) Wiring Harnesses


James_Douglas

Recommended Posts

After just commenting on another topic about how I had a good experience with Harnesses Unlimited for the restoration of the 1949 Desoto, I wanted to ask everyone a question on non-stock harnesses.

 

Next year I will be staring in on the 1947 Desoto Suburban, preparing it for out retirement and x-country driving. As some of you know, it will keep the flathead but the entire car will see extensive modifications including the change to 12 volt.

 

I think the expense and trouble of using a stock harness will not be worth it due to all the electrical changes my modifications will take.  Therefore, I think a modern or hot-rod wiring kit will be in order.

 

My question to anyone who has used such a kit is what is your impression of it? There are a number of makers out there and I would like to start to plan on which one I will use. 

 

I am looking for excellence, and not to concerned on price, as I never want to have any problems with wiring on this car.

 

Thanks for any feedback either directly on this topic or via a private message if you like.

 

Best, James.

Link to comment
Share on other sites

I had to rewire my 39 Plymouth last Summer. Old wiring was rotted and spliced many times. Instead of an original wiring harness, I opted to buy spools of good quality wire in 4 different gauges and re-wire it myself. I used a schematic of the original factory wiring, and had to trace some of it because of some bad splicing and different color codes over the years before I bought the car. I added two fuse panels and have every ciricuit fused plus a master fuse. If a fuse blows, I can locate the problem immediately. With the old system, I would have to probe different directions to find the problem. As I proceeded, I made a schematic of the new circuitry. I added separate high/low beam relays which allows the headlights to have full amperage (brightness). The bulbs are now halogen. The horn barely had any volume and now it's very loud by being on a separate fuse and relay. I added braided ground straps from the engine to body to frame.  In conclusion, it's totally custom modified and most efficient.  If you're not getting it back to original factory specs and modifying for efficient improvement and safety, I'd recommend replacing wires one at a time with good quality wire and proper gauging and add fuse panels and individual circuits. Use the original factory schematic as a guideline.  

  • Like 3
Link to comment
Share on other sites

Planning on adding more accessories like AC, PW, Door locks on and on??

 

I have been looking for a name of a fairly new company on the scene that builds a top of the line setup. I saw this  in a car mag write up but will have to dig some more to locate and advise.

 

DJ

Link to comment
Share on other sites

As Doug (DJ above) knows, I totally rewired my 47 Plymouth a long time ago with a customized Rhode Island Wiring loom.  My car had an alternator, dual headlight relays, turn signal wiring, and lots of other changes from stock.  I gave them a list of all of the changes, discussed the details of where everything was located, and they gave me several harnesses that dropped right in.  Highly recommended.

Marty

  • Like 1
Link to comment
Share on other sites

11 hours ago, James_Douglas said:

After just commenting on another topic about how I had a good experience with Harnesses Unlimited for the restoration of the 1949 Desoto, I wanted to ask everyone a question on non-stock harnesses.

 

Next year I will be staring in on the 1947 Desoto Suburban, preparing it for out retirement and x-country driving. As some of you know, it will keep the flathead but the entire car will see extensive modifications including the change to 12 volt.

 

I think the expense and trouble of using a stock harness will not be worth it due to all the electrical changes my modifications will take.  Therefore, I think a modern or hot-rod wiring kit will be in order.

 

My question to anyone who has used such a kit is what is your impression of it? There are a number of makers out there and I would like to start to plan on which one I will use. 

 

I am looking for excellence, and not to concerned on price, as I never want to have any problems with wiring on this car.

 

Thanks for any feedback either directly on this topic or via a private message if you like.

 

Best, James.

I used YnZ for my 1940 Plymouth wagon. I needed some custom loops for dual taillights and turn signals, which they created and added to the stock '40 Plymouth. I ended up calling them a couple of times and they answered the phone, and were very helpful. Not the cheapest, but very high quality.

Link to comment
Share on other sites

Here's my incomplete answer. A few months ago, I picked up a'50 Desoto. All original, all there. A previous owner had purchased an alternator, 12v coil, and a Speedway 12 circuit mini fuse harness. And, took out most of the original wiring. So, my son and I (mostly him) are installing the new harness. The only troubles he's had are the original turn signal switch needed to come out and have the damaged insulation wires replaced, the column switch doesn't support a hazard circuit, so that wire is tied up out of the way, and the dime light socket being grounded to the body required the socket changed for a separate ground wire for the door switches. In all, nothing tough to figure out. Having something custom made for the car, as others have suggested, would be a great way to go, but my car came with this harness,r so we used it.

Link to comment
Share on other sites

James_,

 

Here is the web page for Couch Controls the company I mentioned earlier.

I have no experience with them at all just appeared to be interesting approach to rewire old vehicles  and all the way up to wanna be new everything in a car, complicate beyond comprehension for most except for the electrical engineers out there.

 

https://coachcontrols.com/index.php?main_page=index&cPath=36

 

My personal experience with Painless wiring was very good are are considered top of the line by many.

Also helped a friend do a complete rewire using a American Autowire Harness that was a nice setup with about 6 pages of instructions and diagrams.

 

DJ

Edited by DJ194950
add contact
Link to comment
Share on other sites

I'm currently installing a painless 21 circuit universal key in dash.   Just wired up the tail end today.  Starting g dash and dolphin gauges next.  So far I love it.  Very nice quality and plenty of extra circuits like ac, 3rd brake, reverse light or neutral safety, stereo, alternator kit, flashers, turn signals, etc. Lots of extra supplies.   $249

 

Link to comment
Share on other sites

Just finished rewiring my 51 Cambridge.  I used the Speedway 22 circuit kit,  the directions are oriented towards a GM setup and are a bit thin.  But I've been tinkering with Mopars for 30+ years and have even more experience with electronics so the directions weren't really necessary for me.  What's nice is the wires are both color coded and labeled.  SInce i converted to 12V and plan to add AC later on it worked for me.

Link to comment
Share on other sites

If you change away from the stock wiring harness, I recommend drawing up a new wiring diagram that reflects any changes that you made.  It will make your life easier when you install the new harnessing, and down the road.  Also, any future owner will appreciate the fact that it was documented if you eventually sell it.  I plan to do that with my '47 Business Coupe, and have already drawn up a diagram in Microsoft Visio.  I've posted a screen shot in my restoration thread.

Link to comment
Share on other sites

@Dennis Detweiler I am working on re-wiring my ‘38 Ply currently. Do you have any pics you could share of your fuse mount location? I am allowed  interested in seeing the type of fuse block you used. Also mention of a master. Details would be great. Thx. 

Edited by keithb7
Link to comment
Share on other sites

Hi Folks,

 

As some of the older posters know, I have a more than sufficient background in things electrical and electronic to do the whole thing from scratch if need be. What I am interested in is folks thoughts on the quality of components from the various players to their customer service when something is not quite correct.

 

I have a preliminary schematic already on paper.    Until I decide on which "computer" I will use for the fuel injection, the control of the electric water pump and fan, the electric power steering and some other issues...it will be some time until I can product a final schematic.

 

One thing I am interested in, and the usual suspects give me dead air when I ask, if if they will make up a harness with cross linked polyethylene wire instead of PVC. The insulation has MUCH higher heat rating than PVC.  When I replaced the engine side wire on the '47 Desoto in 2003 or 2004,  used that.

 

I may end up just end up purchasing parts from American Auto Wire and get my actual wire someplace else.

 

Thanks, James

 

Edited by James_Douglas
Link to comment
Share on other sites

James, if I was building a premium-quality harness I would use Tefzel (ethylene-tetrafluoroehtylene, ETFE) Mil-spec M22759 wire with tin-coated copper conductor. This is what we use in our aircraft and I've gotten spoiled to its quality and ease of use. It customarily is sold with white insulation but other colors are also available. It is used in aero-space due to the lack of noxious fumes when exposed to temps high enough to melt the insulation (>300C).

Edited by Sam Buchanan
Link to comment
Share on other sites

6 hours ago, Sam Buchanan said:

James, if I was building a premium-quality harness I would use Tefzel (ethylene-tetrafluoroehtylene, ETFE) Mil-spec M22759 wire with tin-coated copper conductor. This is what we use in our aircraft and I've gotten spoiled to its quality and ease of use. It customarily is sold with white insulation but other colors are also available. It is used in aero-space due to the lack of noxious fumes when exposed to temps high enough to melt the insulation (>300C).

Hi Sam,

 

I never noticed your "cars". I am aware of that wire, although I have never used it. If my recent back surgery has a good out come, and I will not know for 3 or 4 months, sometime next year I want to start looking for one last vehicle. That will be a Waco UPF-7, A Fairchild KR-34, or if I can handle the fuel requirements a Vultee BT-13...

 

As to fire and wire...let me tell you a story. I had about 6 ships going to dry dock in China. While they were there, my IT staff was charged with having the ships old Token Ring wiring pulled out and Ethernet Cat 5 pulled.  When I talked by phone, from San Francisco with the Yard Master in Asia, I told him to get plenum rated Cat 5. His answer was is that 110V or 220V?

 

I had to get our Port Engineer at the yard involved. The up shot was that in most of Asia, they use PVC even in the large skyscrapers. Can you imagine a two foot thick bundle of PVC wire running up 50 stories or more and then catching fire.  I had to explain to our Chief of Engineering that I was putting seven or eight large spools of plenum rated wire on one of our ships to the yard in Asia. I did not want a fire to happen on a ship and have the guys die from the PVC going up. I also will not spend any time in a high rise building in Asia. 

 

James.

  • Like 1
Link to comment
Share on other sites

15 hours ago, James_Douglas said:

 

I never noticed your "cars". I am aware of that wire, although I have never used it. If my recent back surgery has a good out come, and I will not know for 3 or 4 months, sometime next year I want to start looking for one last vehicle. That will be a Waco UPF-7, A Fairchild KR-34, or if I can handle the fuel requirements a Vultee BT-13...

 

All very nice rides, James......but they will burn a bit more fuel than our flatheads......  ;)

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use