• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Some more EFI swap info needed.

  • Thread starter Thread starter 88 Fox GT
  • Start date Start date Sep 9, 2004

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Sep 9, 2004
#1
  • Sep 9, 2004
  • #1
I ordered my EFI wiring harness last Monday, so it should be here soon. All I have left to do to the engine is mount on the oil pan and timing chain cover and it will be ready. Next, I need to order a new clutch kit then the engine will be ready to install into the car. There are a few things I am going to need to know.

First, I need to know what wires are going to have to be spliced into the stock fuse box, if any.

I also need a quick description of how the fuel pump relay system works and ties in with the ignition switch (i think?).

How about my alternator? I was reading on Hakans website that he forgot to hook up the warning light for the alternator and it caused the battery to go dead on a long drive.

This is just a few of the things I would like to know before I put the engine in the car, just incase. I'm sure I will have many more questions to be answered. Thanks for any help, guys!
 

67coupestang

Founding Member
May 31, 2002
509
2
19
Sep 10, 2004
#2
  • Sep 10, 2004
  • #2
The fuel pump relay is run off the computer, not directly off the ignition switch. Thats how you get the "hold the key on, fuel pump runs for 3 seconds, then crank". Dont know about any battery warning light, but hav you considered using a 3G? I had problems keeping up with all the fuel pumps, and new electrical load with my stock alternator...
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Sep 10, 2004
#3
  • Sep 10, 2004
  • #3
You said you ordered a harness, is it stock or aftermarket made for the swap?
 

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Sep 10, 2004
#4
  • Sep 10, 2004
  • #4
67coupestang, yes I am using the 3G alternator.

WORTH, I ordered the wiring harness from fordfuelinjection.com
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Sep 10, 2004
#5
  • Sep 10, 2004
  • #5
Speed_Demon1965 said:
67coupestang, yes I am using the 3G alternator.

WORTH, I ordered the wiring harness from fordfuelinjection.com
Click to expand...

I would think it would come with a wiring diagram, if it doesn't I can figure out anything you need from the diagrams I have. Just let me know, also if you give me an email and the year make and model of the new engine setup I can send you the oem diagrams, they should help.
 

69Horse

New Member
Mar 19, 2004
8
0
0
Sep 10, 2004
#6
  • Sep 10, 2004
  • #6
Ryan make a really nice harness product wise, peoples only complaint with him is his lack of communications, take a look at his website here's the connections you'll need to tie it in Basically a start signal for the tfi and also a run for the computer.



I know his bronco harness's are pretty straight forward, I didn't know he was making a early mustang version

/Allen
 

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Sep 10, 2004
#7
  • Sep 10, 2004
  • #7
His harness has to be the best one in the industry for the classic Mustangs. I have seen the others, their prices and layout can't compete. His is so simple looking. All one piece and $475 vs $600-$1000.

At first, I was asking him a few questions about it and he was very responsive. But, since I have ordered the harness, I have gotten nothing from him. No e-mail or anything confirming that he got my order and/or shipped it out. I even sent him an email asking about my order and have gotten no response so far. I'm kinda disapointed about that.

69horse, thanks for the diagrams. Guess I didn't notice them on his site.
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Sep 10, 2004
#8
  • Sep 10, 2004
  • #8
He's probably busy spending all that cash he made.

OR

Putting your harness together.
 

69PaleHorse

Member
Feb 3, 2004
264
0
16
Ventura County, CA
Sep 10, 2004
#9
  • Sep 10, 2004
  • #9
I think I want Fostang to help me build my conversion harness when it's time.
 

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Sep 10, 2004
#10
  • Sep 10, 2004
  • #10
Fostang said:
He's probably busy spending all that cash he made.

OR

Putting your harness together.
Click to expand...

Yeah, I was thinking that could be a possibility also. He may be putting it together.
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Sep 10, 2004
#11
  • Sep 10, 2004
  • #11
69PaleHorse said:
I think I want Fostang to help me build my conversion harness when it's time.
Click to expand...


Sure no problem.
 

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Sep 11, 2004
#12
  • Sep 11, 2004
  • #12
Does anyone have a picture of their EEC mounted in the car? I am putting mine behind the glove box, but would like to see pics if you guys have them.
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Sep 11, 2004
#13
  • Sep 11, 2004
  • #13
up above the heater box.

NOTE: Don't drill into your cowl for the mounting brackets.

Sorry no pics as it's too hidden.
 
You must log in or register to reply here.

Similar threads

Alternator not charging
  • SchwarzStock
  • Jul 6, 2026
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
2
Views
132
1965 - 1973 Classic Mustangs -General/Talk- Jul 19, 2026
SchwarzStock
T
Electrical Brown Connector #31
  • ta66
  • Jul 26, 2026
  • Fox 5.0 Mustang Tech
Replies
2
Views
131
Fox 5.0 Mustang Tech Jul 30, 2026
ta66
T
A
Blow through intercooled questions
  • AngryH58
  • Monday at 1:27 PM
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
5
Views
73
1996 - 2004 SN95 Mustang -General/Talk- Tuesday at 10:50 AM
AngryH58
A
Ford truck engine swap issues
  • keel
  • Jul 7, 2026
  • Other Auto Tech
Replies
17
Views
438
Other Auto Tech Jul 13, 2026
General karthief
1
Electrical Headlight harness trouble
  • 1985fox
  • Apr 14, 2026
  • Fox 5.0 Mustang Tech
Replies
7
Views
335
Fox 5.0 Mustang Tech Apr 17, 2026
AeroCoupe
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?