Thread: wiring for EFI to carb question

I removed the efi from my 89 Range Rover and replaced it with an edelbrock manifold and quadrajet carby.
I just removed all the efi wiring loom to the injectors from the engine bay and in the cab from memory. I dont remember needing to alter the coil or starter motor wiring. You will need to rewire the fuel pump as there is a timer that is run from the air flow meter that only runs the fuel pump for a short time if there is no air flow. That had me confused for a couple of hours.

Hi Nat, starter and fuel are run through relays in the loom, not through the ECU but the fuel relay is run through the ECU, the starter is not. You will need to run a new feed to the fuel pump relay. Have you changed the tank to a carby setup, or still using the EFI tank? If you are still using the EFI tank, remember the fuel pump will have too high a pressure for the carby.

If your up to the wiring, you must be getting along ok.

Still trying to find time to drop in one evening to have a look.

Cheers - Gav.

Hay Gav,
Yep motoring along,
We are using an EFI tank modified so its now using a mech fuel pump to suck and push. We were going to use a Holley red, but was told Electric fuel pumps don't suck well, so went mech instead.

Hay the coil, theres 2 wires;

White = power hence goes to the pos side of coil.
Black = Neg, so neg side.
Other colour ( I cant remember) where does this go?

Cheers nAT

OH, I want to start it for the first time in 2 weeks, I reckon I'm almost there... well theres a **** load of little jobs, but I just want to start it/drive it.

Always welcome Gav! We mainly do "car day" on sundays.

Cheers NAT

Originally Posted by nat p

Hay Gav,
Yep motoring along,
We are using an EFI tank modified so its now using a mech fuel pump to suck and push. We were going to use a Holley red, but was told Electric fuel pumps don't suck well, so went mech instead.

Hay the coil, theres 2 wires;

White = power hence goes to the pos side of coil.
Black = Neg, so neg side.
Other colour ( I cant remember) where does this go?

Cheers nAT

Hmm, can't recall what the other wire does. In the main loom, I just have the 2 plus the wires running from the dizzy to the amp. There were other wires in there that I pulled out when I re made the loom, but everything I pulled out wasn't connected at one end...

Maybe it doesn't do anything... we need Bee Utey to chime in here.

Also, with the fuel pump - you were told right. If you bleed up the electric pump, it will suck fine, but they tend to loose their prime easily, then you are stuffed. We use them a lot on small diesels above the tank where the factory mechanical pump struggles. They work fine, but we have to put a priming bulb in before them (like you see on small boat fuel tanks) for if/when they loose their prime.

On the standard Rangie carby setup, the electric fuel pump is mounted on the LHS chassis rail, and has a flooded inlet from the tank to avoid this.

Cheers - Gav

Hay ball,

I've attached a pic. So I've got 12v (when ignition is on) on a white one, black is neg (cos I checked the continuity) but beggared what the other 2 wires do?
These two wires should go to pos and neg sides of the coil. Can anyone shine a bit of light?


Cheers Nat p

Hey Nat, what kind of dissy and coil does the Chev use? It's no good asking what to connect without knowing what you're connecting. Pictures? And as for black wires, no good reason to connect them to the negative side of the coil unless you have it coming off an electronic module. It won't be an earth wire, your coil negative gets pulses to produce spark, an earth would just short it out and blow it up.

Thinking about my conversion a bit more (it was more than 15 years ago) there was two wires from the coil that ran to the efi loom. You only need two wires for a carby set up. Positive from the ignition to the coil and negative.