Painless harness conundrum

[inkslingrrr]

Once more I ask the gurus on this forum for assistance…

A few questions in regards to the wiring harness I am putting in my 71 C10, sbc 350, nothing fancy…running stock gauges, however I will be wiring in an MSD box with this 🙈…now the MSD box has a purple wire and a green wire braided together which was plugged to the underside of the distributor, tach and battery position.
First question:
1. What do I do with wire #923 purple wire from fuse block
Simple question on side note… wires that are not to be utilized, can they be cut back and disregarded?

Thanks for your time

[cj847]

I don't think we can answer your question without more information.

What distributor are you using? HEI or MSD? What MSD box?

I think 923 is the tach signal wire which would connect to a gray wire on a digital MSD box. Not sure on the old MSD boxes. You need to download the MSD instructions off the internet for your particular unit. The instructions are pretty clear.

On unused wires, I usually put a short piece of shrink tube on the ends after I cut them to whatever length I decide to leave. This will prevent accidental shorts or grounds. If you want a super clean install and are sure you'll never use the circuit, you can unpin the wire from the fusebox.

[May70]

I have not specifically used that harness brand (yet) but I am also fairly confident there is a manual with wire colors identified.

No way id even start that without having all the wires identified first. That's asking for trouble.

If you cant find it you can call them, I have spoken with their tech support a few times. It may have been a longish hold but they had good info.

Not sure which harness you have but this is for harness numbers 10101-10104:
https://www.painlessperformance.com/Manuals/10104.pdf

There should 100% be a detailed guide available.

Also some mfg's do have small print on the wires (not trying to insult you), maybe double check down the wire too.

[OneOffStroker]

Originally Posted by inkslingrrr

Simple question on side note… wires that are not to be utilized, can they be cut back and disregarded?

I think the other fellas did as good of a job as any of us could without knowing the exact MSD box and other particulars of your setup.

Extra wires can be cut back and disregarded, but if you do that, then make sure to pull the fuses that power those wires so that the little bit of copper at the ends doesn't ground on something and cause problems or worse (fire)

Personally, I just roll back all the wire into loops, and then zip-tie it up and away from everything or tuck it under the carpet if I can (still remove the fuses though). You never know when you may want to add something in the future: heated seats, power window & locks, electric fan, fuel injection, USB power, etc. It's just nice to have an available pre-wired circuit for those unforseen 'upgrades' to make your old truck fit in with today's modern creature comforts.