Carb to EFI

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
I want to convert my 1980 Mustang over to efi. I know the basis of what I need, but there is a few areas that I am not sure on.

I know I will need:

Electric fuel pump
Sensors
Injectors/MAF
Fuel rails/lines
Computer
Upper/lower intake manifolds
Injector harness and computer harness

What I am not sure on is what I need to do to make it work for where the harness would plug into the body harness to inside the car. I want to keep the original interior and gauges and such, so I don't know what I need to do here. I was thinking maybe use a body harness out of an EFI 86 since the interior is fairly similar, but I don't know if that would work haha. :shrug:

Any info has to what harness I would need to make it work would be wonderful :)
 
Your primary concern will be the EFI harness, and which wires on the harness need power and ground.

Here's a site with lots of EFI diagrams and helps...



Diagrams courtesy of Tmoss & Stang&2birds
88-91_5.0_EEC_Wiring_Diagram.gif


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds
(website host) for help on 86-95 5.0 Mustang wiring Mustang FAQ - Engine Information Everyone should bookmark this site.


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

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 94-95 5.0 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

Vacuum Diagram 87-93 Mustangs
The diagram says 88 Mustang, but except for the vacuum line connected to the MAP/Baro sensor, it is the same for all 5.0 Mustangs from 87-93. The 89-93 Mustangs vent the MAP/Baro sensor to open air.
http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
 
To the best of my knowledge, there isn't a simple harness swap that will do the job. If you use junkyard parts, you would have to swap the harnesses for the engine, front of the car and the dash harness too.

I believe that there are people who have done what you want to do, you will just have to do a lot of searching to find them.

The primay items on any stock 89-93 Mustang EFI harness will be the computer power, computer ground and fuel pump wiring. If you cannot read electrical diagrams and make wiring changes, this isn't a project that I would recommend for you to attempt using a stock harness from the junkyard.

There are harnesses for conversion of early Mustangs to EFI. They will allow you to use EFI engine & computer in just about any car. However they are expensive, $535-$575. That price does not include the computer, or any sensors.

See Summit Racing for more information
http://www.summitracing.com/search/?keyword=Ford EFI harness&dds=1

Download a ford Racing Products catalog for mor information on the Ford Harnesses.
See http://www.fordracingparts.com/2010-catalog/
 
I might be doing the opposite of what your doing, would you be interested in a trade for all my EFI stuff for all of your Carb stuff? I'm still not 100% on doing this yet though, I need to figure out how to get around emissions first. And to keep your thread on topic, you can PM me.