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Aero to four-eye conversion - wiring up headlights

  • Thread starter Thread starter Darkwriter77
  • Start date Start date Apr 18, 2009

Darkwriter77

Resident Ranting Negative Nancy
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Apr 18, 2009
#1
  • Apr 18, 2009
  • #1
Before any of y'all go screaming about the blasphemy of swapping four-eye noses onto Aero Foxes and vice-versa, let me just state that what we're doing here is UN-converting an '80 Capri that had a '90 Mustang front end swapped onto it. We're trying to right the wrongs that Lynn's ex-hubby committed with this car.

The thing I'm having an issue with trying to figure out here is that when this car was converted, all the wiring and everything from a '90 was used. So basically, this should be regarded in the technical sense of putting a four-eye nose on an Aero car (even though this is actually a four-eye nose going onto an original four-eye). The Aero headlights are 3-wire, and the four-eye lights have 3-wire plugs for the low beams and 2-wire for the high beams. We kept the plugs and a bit of extra wire from the donor Capri where we got the nose and hood and such, but I'm not sure how to go about splicing this into the 3-wire setup, or (if I need to run all-new wire to something) how exactly to set this bugger up differently.

I have wiring diagrams in my Chilton manuals, but half of it is like Japanese to me, and I can't quite figure how to transfer one to the other. From what I gather, as far as the Aero 3-wire setup goes, there'st one power wire for each beam (one for low beam, one for high beam) and one ground shared by both on each plug. As far as the four-eye setup, though ... I dunno. Is the three-wire on the low beams including one ground and two different power wires, and the second power wire is activated on a separate circuit along with the high beams?
 
J

jfman

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Apr 19, 2009
#2
  • Apr 19, 2009
  • #2
Good luck with your project and screw thw purists. I would like a four eyed swapped aero car myself.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
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Apr 19, 2009
#3
  • Apr 19, 2009
  • #3
jfman said:
Good luck with your project and screw thw purists. I would like a four eyed swapped aero car myself.
Click to expand...


It's actually a factory Capri with a Mustang aero nose on it that they're putting BACK to 4 eye status
 

NIKwoaC

中國製造
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#4
  • Apr 19, 2009
  • #4
jfman said:
Good luck with your project and screw thw purists. I would like a four eyed swapped aero car myself.
Click to expand...

Haha, did you read Darkwriter77's post at all? He IS one of these purists you're ragging on!

Darkwriter- My best suggestion to you is to look into your own '84 and try to translate what you have going on there to the Capri.
 
L

lang williams

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Apr 19, 2009
#5
  • Apr 19, 2009
  • #5
i'll be following this...my 84 t top notch was converted before i bought it an some day i'd like to change it back.
 

Darkwriter77

Resident Ranting Negative Nancy
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Apr 19, 2009
#6
  • Apr 19, 2009
  • #6
Well, LaserSVT suggested instead of running two 2-plug lights (the high beams) and two 3-plug lights (the low beams) that I should just go with all four 2-plug lights, or just hook up two of the three wires on the low beams, and go about it that way. Seems simple enough and it kinda makes sense, but I'm just concerned about whether or not the wire can handle it. Should I just run thicker ground wires straight from the bulbs to the frame, rather than splicing them into the stock ground wires? (Otherwise, I'd have two bulbs per ground wire on each side sharing a ground wire.)
 

FrankenStang

Now, give me a damn CT!
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Apr 19, 2009
#7
  • Apr 19, 2009
  • #7
jfman said:
Good luck with your project and screw thw purists. I would like a four eyed swapped aero car myself.
Click to expand...
Lack reading skills much?

Read carefully...

Darkwriter77 said:
Before any of y'all go screaming about the blasphemy of swapping four-eye noses onto Aero Foxes and vice-versa, let me just state that what we're doing here is UN-converting an '80 Capri that had a '90 Mustang front end swapped onto it. We're trying to right the wrongs that Lynn's ex-hubby committed with this car.
Click to expand...

NikwoaC said:
Haha, did you read Darkwriter77's post at all? He IS one of these purists you're ragging on!

Darkwriter- My best suggestion to you is to look into your own '84 and try to translate what you have going on there to the Capri.
Click to expand...
X1000.
85_SS_302_Coupe said:
It's actually a factory Capri with a Mustang aero nose on it that they're putting BACK to 4 eye status
Click to expand...
http://forums.stangnet.com/764657-p...cury-capri-aero-four-eye-progress-thread.html
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
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Apache Junction, AZ
Apr 19, 2009
#8
  • Apr 19, 2009
  • #8
Looking at my '84 won't tell me much. I have the four-eye plugs and all from the donor Capri and that's exactly the same as what's on my '84. I already know how the four-eye STOCK setup should be, as well as the Aero setup, because I have functional examples of each (the Black Pearl and teh Notch); the question is not how it's setup up in stock form, but rather how to graft the two together.

Only idea I've got so far that sounds logical is simply running the low-beam and high-beam headlamps as two-wire setups (basically like four high-beams) and running separate grounds for each instead of having them share ground wires. Then I can just splice into the low beam and high beam Aero positive wires and run those to the four-eye bulbs. Kinda hard to explain in words. I tried to map it out semi-visually in another thread over in 5.0 Talk:

http://forums.stangnet.com/7880123-post98.html
 

93 LX

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Apr 19, 2009
#9
  • Apr 19, 2009
  • #9
If I remember correctly the high beam is split to go to the "hi" in the dual beam and to the hi beam only light. In my 82 if you peal back the wiring for the hi beam on the dual beam socket you will see it loops to the high beam only socket. I hope this helps. BTW nice to bring back the Capri, arent many of them left. I am glad I kept my 82, which I bought new in 82, when it got crashed in 88. I love those 4 eyes Foxes...
 

stang&2Birds

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Apr 19, 2009
#10
  • Apr 19, 2009
  • #10
I'm not sure that I see where the problem is.


87+ headlights:






86 headlights:




So, just remove the high-beam connector on the 90 wiring harness and put on the 4-eye high-beam connector. Connect green to green, and black to black. Tape off the read wire.

If I remember correctly, you can just put the 3-prong connector on the 2-prong headlight, and it'll work correctly (high-beams only).
 

jrichker

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#11
  • Apr 19, 2009
  • #11
Sharing a ground will not be a problem. Just remember to increase the ground wire size one size larger.
Example: if original ground wire was a 16 gauge, use 14 gauge or even a 12 gauge.

On both the 90 and 80 model cars, the red/black is the headlight low beam power

On both the 90 and 80 model cars, the Lt green/black is the headlight high beam power.

On both 90 and 80, the black is the headlight ground.

The red/black & Lt green/black wires connect to separate terminals on the low beam bulb. There is a high beam and low beam filament in the low beam light bulb. The black wire connects the the common ground.

The Lt green/black wires connect to the single filament in the high beam bulb. The black wire connects the the common ground.

The AutoZone diagrams should be very helpful.

80 model Capri body wiring diagram:
http://econtent.autozone.com:24991/...00c152/80/04/e2/90/large/0900c1528004e290.gif

90 model Mustang body wiring diagram:
http://econtent.autozone.com:24991/...00c152/80/06/96/82/large/0900c15280069682.gif
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
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Apache Junction, AZ
Apr 19, 2009
#12
  • Apr 19, 2009
  • #12
Awesome! That'll work.

I was under the impression that the four-eye cars had some kind of totally different circuit going on for the high beams as opposed to the Aero cars. So, basically what it looks like I need to do is just run low beam to low beam (positive) and high to high (positive) and then, just for the sake of having good grounds and all, just run separate ground wires for all. Easy enough.

Many thanks! Probably won't be until next weekend 'till we get around to doing the nose/hood swap, but from the looks of it, things shouldn't take too long.
 
J

jfman

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Jan 13, 2006
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Apr 20, 2009
#13
  • Apr 20, 2009
  • #13
85_SS_302_Coupe said:
It's actually a factory Capri with a Mustang aero nose on it that they're putting BACK to 4 eye status
Click to expand...

NikwoaC said:
Haha, did you read Darkwriter77's post at all? He IS one of these purists you're ragging on!

Darkwriter- My best suggestion to you is to look into your own '84 and try to translate what you have going on there to the Capri.
Click to expand...

~FrankenStang~ said:
Lack reading skills much?

Read carefully...




X1000.

Click to expand...


Guyz: Of course I read the OP!!! This is just how I feel Build what you want to build not what people tell you to build. I was considering doing this to my 91 last year and posted up about it on foureyedpride and they locked the thread.
 

FrankenStang

Now, give me a damn CT!
15 Year Member
Apr 16, 2005
4,461
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Florence, Az
Apr 20, 2009
#14
  • Apr 20, 2009
  • #14
jfman said:
Guyz: Of course I read the OP!!! This is just how I feel Build what you want to build not what people tell you to build. I was considering doing this to my 91 last year and posted up about it on foureyedpride and they locked the thread.
Click to expand...

That's because FEP's sole existence is to preserve foureyed cars. They are Purists and you know what? That's ok. They have their reason's for doing what they do.
 
J

jonathan myers

New Member
Mar 29, 2016
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Oct 30, 2020
#15
  • Oct 30, 2020
  • #15
Darkwriter77 I'm taking my 85 and taking the wiring and all from my doner 91 I wish to keep it a 4 eye car like it is originally never done much wiring so how exactly would i go about putting the two together I've read this whole thread a couple times and I'm having a hard time making sense of it
 

General karthief

wonder how much it would cost to ship you a pair
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#16
  • Oct 30, 2020
  • #16
Using the 91 wiring could be problematic, the 91 has two head lights and the 85 has four, also turn signal wiring and side maker wiring could be a problem.
 
J

jonathan myers

New Member
Mar 29, 2016
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Oct 31, 2020
#17
  • Oct 31, 2020
  • #17
General karthief said:
Using the 91 wiring could be problematic, the 91 has two head lights and the 85 has four, also turn signal wiring and side maker wiring could be a problem.
Click to expand...
From what I saw it looked like the markers and blinkers would be good rn it's just the 4 headlights and I've got the original 4 eye harness out of mine what I want to do is chop both somehow and wire em together I've got a soldering gun and heat shrink gun just bot the knowledge of what goes to what how to wire it up and still have lights which wire goes where and how to jump two to four I've seen multiple aero conversion keeping the 4 eye nose I just need to figure out what they did and do the same
 
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