Ditching CIS for carbs - wire loom

[toddu]

When switching to carbs, it seems there is a lot of the wiring harness that is not needed. But, things like oil pressure sending unit, reverse light switch, etc. is needed.

Do you just piece through the wiring harness and remove what is no longer needed? Any good write up on here? Is the fuse panel in the engine bay still needed (also moving to MSD)?

Todd

[Flat6pac]

Tape your harness up, dont cut it, they are getting too hard to find useable.
Bruce

[toddu]

I'm really just talking about the CIS harness inside the engine bay. I'll leave the Lambda, etc. for now. It seems like there are only a few non-CIS related wires (e.g. - the oil pressure switch), so I'm not sure how to deal with those. They get "cut" (just remove tape and separate from bundle) from the rest of the harness? Do these feed into the 14-pin connector?

Todd

[HawgRyder]

I think what Bruce is saying...fold back the unused connectors (tape or heat shrink the ends) and re-package the harness to look good.
This way...if you sell the car...and the new owner wants to return to stock...all the wires are still there.
Bob

[Nostril Cheese]

I'd get the Bentley and figure out what is needed and what isnt.

I'd just build my own harness, using the factory plug and save the factory harness (PLEASE dont cut it up)

[toddu]

Originally Posted by Nostril Cheese

I'd get the Bentley and figure out what is needed and what isnt.

I'd just build my own harness, using the factory plug and save the factory harness (PLEASE dont cut it up)

So, I just need to get what's needed (reverse switch, oil pressure, etc.) to the factory 14 pin connection?

Todd

[timmy2]

Remove the old harness completely and build a new one with everything you need on the engine from the starter to the 14 pin connector, or insulate and wrap the unused wires to the loom as others have suggested. I used electrical tape, heat shrink and wire ties to hide the CIS wiring when I installed the EFI.

[dipso]

It's complicated,, but some of it isn't needed. What I did was first, take a picture, write it down, find a chart, something. Just make sure you know the locations of each pin in the connector.
They are all color coded on the wire and numbered on the connector. It is easy to get them in the wrong place if they pop out on you. And they will.

Then leave the wires in the connector on the loom side and just pull out the ones you don't need on the engine side. They pull out of that pin connector easily, once it's opened.
It's really hard to say exactly what is needed and not needed. Just be careful and thorough. You can figure it out.

The three fuse panel in the engine isn't needed either, but I kept mine anyways. I wanted a convenient source of power for a timing light or whatever back there.
I ran a heavy gauge wire from the starter to the fuse block, and then connected the MSD units to that.

Mine is a 75, so I am sure it is different than yours. But yes, it is possible.
Here is a picture and you can see the little fuse block mounted above the lower left MSD.
Good luck.

[dipso]

If you do a search on '14 pin connector' you will find plenty of details and diagrams.

[boyt911sc]

Originally Posted by toddu

When switching to carbs, it seems there is a lot of the wiring harness that is not needed. But, things like oil pressure sending unit, reverse light switch, etc. is needed.

Do you just piece through the wiring harness and remove what is no longer needed? Any good write up on here? Is the fuse panel in the engine bay still needed (also moving to MSD)?

Todd

Todd,

Based from my initial look at the 14-pin connector, you would be needing at least 9 connectors if you delete your engine heater blower:

1. Ignition SW @50 to starter @50.
2.
3. Oil temp. indicator to oil temp. sender.
4. Oil press. indicator to oil press. sender.
5. From fuse #11 to back-up light switch.
6. Rear back up lights to switch.
7.
8.
9. Oil press. indicator light to oil press. switch.
10. Fuel pump relay @ 30 to FP.
11. generator charge indicator lamp to alternator @ D+.
12. Tachometer @ TD to ignition module (CDI or MSD).
13. (heater blower relay) delete
14. (heater blower motor) delete

Tony

[toddu]

All great info (and pigs). Thanks!!!

Todd

[SCOTITUDE]

didnt wanna cut anything so i wrapped up all the unused connectors and they live here now. Bothered me for a while cause it didnt look "clean" but I got over it.

[toddu]

Probably a stupid question, but the fuel injection 14-pin connector is free to go? Both on the engine side (obvious) as well as the plug near the rear shock tower, all the Lambda stuff, etc?

Todd