I'm in the process of putting together a 71 demon. I've ripped out all the existing wiring harness (they were junk) and now in the process of figuring out which way / how to replace everything.
I plan on running a MSD 6AL-2, Electronic gauges, Electric Water pump, Electric fan's and at least one maybe two fuel pumps.

This will be a 80% drag car but still want the ability for factory turn signals / brake lamps / headlights.

I talked to painless but it seems to be a pain!

Advise?

bump

I like American Autowire harness kits.

I just wired my race car so a bit easier from what you are doing. Decide what you want. Do you want original style connectors?
Are you planning on using the original column?
Both American Autowire and Ron Francis make a nice kit
Or you could get a wiring board from someone like Leash Electronics
and start from scratch. They have a Pro Street Wiring Board which will do all your lights and other stuff.
The hardest part of wiring is making it look nice.

Thanks, I plan on keeping the stock steering column but ok with using a push button start and not the key. Not terribly concerned with factory connections

What are you looking for in a harness?
1. Factory fit/replacement or Universal fit?
2. Looking for a "kit", or custom wiring?
3. Is weight an important factor, IE Teflon wiring?
4. Cost can be all over the place depending on what you are doing.

First I would look at what wire insulation is being used.
Stay away from cheap PVC/GPT wiring. Look for cross linked polyethylene wiring, usually SXL/GXL/TXL wire. It can withstand higher heat, abrasion, and aging than GPT wire.

Might want to call Ron Francis Wiring?
http://www.ronfrancis.com/

If you have most of the factory stuff in the car and want it to function, a reproduction harness may be easiest. Then do a separate system to run the add-on, race stuff. Make it hot through a separate power source from the battery, and a constant duty solenoid controlled by an ignition ON circuit. Use separate switches and relays for pumps, fans, etc. We've done this for guys who insisted on keeping the factory wiring and having everything work and it work out well. Factory style connections and terminals will make it easier to use OE switches and components instead of cobbling together a mixture of parts.

Or step up, use modern fuse panels and components and do it from scratch. Some guys want to use the OE ignition switch which is fine. Invest in good parts and pieces instead of the junk they sell at the auto parts. I've used Painless and some of the other "universal" kits that the owner already had, but had to modify and make do so much, I just prefer to do it from scratch since everyone has different requirements.

one thing i might add when it comes to wiring, as i have had to fix many times, and am in the process again as we speak, is practice terminating your connections using a QUALITY crimp tool before you begin. i can't stress this enough. every time i have had to fix wiring issues, it seems the tool used to crimp the terminals was the one that comes with the 2,367pc terminal kit from the elcheapo store made in lacheapistana. there are utube videos that show the correct termination process of almost all the common connectors in use today, so if a guy isn't familiar with how to do this properly, i strongly suggest you view some, then get some spare wire and extra terminals and practice. also, use quality heat shrink. it really isn't as hard to do correctly as some [most ?] think, and i find it kind of fun. what is not fun however, is chasing down someone's poor wiring problems and correcting things that shouldn't have been done in the first place. and the last piece of advice i have is to NOT USE CLAMP ON BATTERY TERMINALS ! those things are a major irritation to me, as most do not conduct current very well because of not having a secure connection, which also allows moisture to wick into the battery cables, causing all sorts of problems. i am not slamming the skills of the OP, as he may be perfectly skilled in this issue. just pointing out issues i have dealt with in the past, and continue to repair quite often. you can do it ! take your time, plan out the best routing to use for your harness, and use QUALITY components and tools, and you will be successful with a harness that will be problem free for many years !

I recommend getting yourself a weatherpack kit, makes for a very professional installation and they are relaible and allow easy disconnection and reconnection.
For "from scratch" harnesses for hotrods and race cars, I usually use a bulkhead multipin connector and have one firewall penetration, always turns out nice...

moparx has good advice.
I used deutsch connectors and Non-Insulated crimp connectors with heat shrink. The deutsch connectors are fun to make.
I bought a few things for my wiring project from here.
https://theelectricaldepot.com/

Also used these battery cable ends
https://theelectricaldepot.com/battery-t...nal-clamps-lugs

Agreed. A good Klein 1005 or other crimp tool is key. Want good crimps, use uninsulated terminals, toothed crimp tool and shrink tube.

I have taken apart other suppliers relay harnesses and you can't believe the poor crimps, especially the chinese sourced product. Crimps that were done and don't even capture the wire or insulation. Had one kit where 30% of the crimps were not correct.

If you mess up a crimp, cut it off and start over. Nothing is worse than chasing electrical gremlins that are hidden under insulation and shrink tube!

For the OP, think through the electrical supply to all the auxiliary items and use relays. If using the mopar style charging system you have to be very careful where you pull power.

Weatherpack are great, but are limited to 20 amps IIRC. Some fans pull a bunch more than that. Most other items are going to be below that threshold. I use weatherpacks a lot on my stuff, especially ignition boxes. Can swap out a box to test another in under 1 minute...

Everything done for you/plug & play sure are the way to go IF you trust the (other guy) to do it right!

I have to admit, the time to install my Painless harness was longer than I estimated, BUT, I was confident of all my terminations.

Soldered all high current carrying leads and had very few gremlins, mostly because it is a somewhat generic kit.

I purchased a Terminal Supply Kit so I had all the terminals I preferred
and the system worked at first start-up.

My 2 cents...Joe

P.S. Ordered a second one for our 71 RR

I use amp connectors for ring terminals, they have a metal sleeve that crimps up on the insulation and acts as a strain relief. http://www.mouser.com/pdfdocs/ENG_DS_82042_StdTermsSplices_0708.pdf

I also buy cheap zip ties, run the wires to where they are going, zip tie in place, if you need to add another wire, more zip ties until its done then cut off the majority and finish by using only zip ties with the metal locking clip. I got the last bag of 300 from Fastenal for $46.00.

LOTS OF GREAT ADVISE! I really appreciate it! I'm going to make the call to Ron Francis today and order some stuff you guys recommended and see what comes of it.
Thanks again!