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Need help with EFI harness modification for 64 1/2 Mustang

  • Thread starter Thread starter ballajb64
  • Start date Start date Oct 27, 2008
B

ballajb64

New Member
Jul 13, 2006
76
0
0
California
Oct 27, 2008
#1
  • Oct 27, 2008
  • #1
I am doing the EFI swap in my 64 1/2 Mustang. I plan on going with a 89+ motor because of mass air. Does anyone have any information on modifying the harness to fit my classic mustang. Any information or diagrams would be greatly appreciated.
 

gonzothegreat

Member
May 4, 2004
421
1
16
London (uk)
Oct 27, 2008
#2
  • Oct 27, 2008
  • #2
Ford Fuel Injection Wiring Harnesses
 
B

ballajb64

New Member
Jul 13, 2006
76
0
0
California
Oct 27, 2008
#3
  • Oct 27, 2008
  • #3
thanks

I will be checking this link out asap
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 27, 2008
#4
  • Oct 27, 2008
  • #4
I just did the swap, it was very easy.

Great link for older harness: Ford EFI Swap
Wiring: http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

In 92 they switched to a slightly different setup.

Let me know if you need any assistance. The swap took me about 8hr to plan the wiring, do it, run the fuel system and put down the lower intake (I used stock engine and custom made chip for the firing order etc). Started on first crank, runs great around the neighborhood. I need to tuck some wires away then I'll drive it to the shop and weld in some O2 sensors and put it on the dyno to tune. Until then I am running it in open loop.

Wes
 
R

rc4mike

Member
Oct 10, 2006
142
0
16
Oct 27, 2008
#5
  • Oct 27, 2008
  • #5
Stanger007 said:
I just did the swap, it was very easy.

Great link for older harness: Ford EFI Swap
Wiring: http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

In 92 they switched to a slightly different setup.

Let me know if you need any assistance. The swap took me about 8hr to plan the wiring, do it, run the fuel system and put down the lower intake (I used stock engine and custom made chip for the firing order etc). Started on first crank, runs great around the neighborhood. I need to tuck some wires away then I'll drive it to the shop and weld in some O2 sensors and put it on the dyno to tune. Until then I am running it in open loop.

Wes
Click to expand...


what chip did use? i have a 408 stroker with a9l computer. Engine runs fine, but have not driven it yet. Still need front suspension installed. Need a chip, not sure who to go with.

Mike
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 28, 2008
#6
  • Oct 28, 2008
  • #6
rc4mike said:
what chip did use? i have a 408 stroker with a9l computer. Engine runs fine, but have not driven it yet. Still need front suspension installed. Need a chip, not sure who to go with.
Click to expand...

I have a twEECer on it now. I will eventually burn a Moates.net chip with my tune once I am done datalogging the computer and tuning it on the dyno.

Wes
 
R

rc4mike

Member
Oct 10, 2006
142
0
16
Oct 28, 2008
#7
  • Oct 28, 2008
  • #7
i am looking at the tweeker, sure looks complicted. How was the tuning for you? I have never done this. Not sure i want to spend all that time learning how to operate the tweeker.

mike
 

Stanger007

Founding Member
Sep 26, 2001
2,015
2
46
Baton Rouge, LA
Oct 28, 2008
#8
  • Oct 28, 2008
  • #8
rc4mike said:
i am looking at the tweeker, sure looks complicted. How was the tuning for you? I have never done this. Not sure i want to spend all that time learning how to operate the tweeker.
Click to expand...

I tune professionally so something like this is just another car to tune for me.

When I got started several years ago the learning curve was steep. I had a great understanding of the mechanical side and how carbs/ignitions systems worked so once I was able to mentally identify what was happening in the EFI system and related it back to my carb knowledge things began to fall into place. I also have a computer science/programming background so that lends itself well to understanding and reverse engineering things when something isn't quite clear.

Getting into tuning is definitely not a cheap endeavor in both money and in time. You will spend a LOT (a LOT!) of time researching and trying things. I would consider having a wideband a necessity in order to properly tune your vehicle. A laptop and the chip and software (I really like BinaryEditor - about $60) are also necessary.

If this isn't for you then I would find a COMPETENT local tuner that can handle your car or ship it off to someone who can tune it to perfection so you can focus on other aspects of the vehicle instead of constantly fiddling with it... when you know how to mess with the tune you will NEVER be satisfied and always wanting to try something new... it is a disease.

Wes
 
P

phutch11

Member
Nov 14, 2005
328
2
18
Oct 29, 2008
#9
  • Oct 29, 2008
  • #9
Did it myself with a Haynes manual wiring diagram. Take your time and document everything you do and you'll see that its pretty easy.

I'm running an untuned A9L but if I were to do it over I'd probably go with a standalone MegaSquirt system - much cheaper than Tweecer and apparently much more documentation and support.

Good luck...

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