wiring fuel pump

[worknon10s]

going from efi to carb on my 93 460 build. would it would to use the existing fuel pump wiring and tie it into the external holley pumps?

if not, why?

 

[jrichker]

going from efi to carb on my 93 460 build. would it would to use the existing fuel pump wiring and tie it into the external holley pumps?

if not, why?

Two questions:
1.) Can you read elecrical diagrams?
2.) Do you understand that when you remove the computer, the fuel pump control relay doesn't have a clue when to turn on and off? Leaving the computer in place to control the fuel pump is not quality workmanship.

You can use the wire & relay, however, it requires some knowledge of electrical circuits to NEATLY reconfigure them to work with a carb setup. The stock fuel pump relay uses a ground to complete the circuit & energize the coil. You would have to move several wires around in order to provide a ground for the relay coil and use the ignition switch to provide the power for it.

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model Mustangs

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

 

[jrichker]

This is the diagram you need...

This assumes that you leave the computer's main engine wiring harness in place. It contains the fuel pump relay,
which mounts under the MAF and near the A/C WOT cutout relay.

The Lt blue/orange wire on the fuel pump relay gets connected to ground. The red wire gets cut &
spliced to a keyed power source. The preferred power source is the red/green wire on the ignition coil.

See http://fordfuelinjection.com/?p=7 for some wiring tips & proper soldering techniques.