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8pin rectangular connector

New User
Posts: 8
Joined: 02/14
Posted: 06/22/14 08:50 PM

Currently I have a '67 Mustang Convertible which I am turning into a restomod with help from an '87 5.0 EFI HO,my wiring comes from an '89 (which was advised for me to use) and I am using MassAir.
I am really stuck do you know where the 8 pin-connector (rectangular) is on the harness ?
Also what connects from the 8pin-connector to the harness as I don't seem to have a port for this, do I need to swap out the harness ?
Is the inertia switch connector next to the 8pin connector ?

thanks so much for your help  

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Posts: 127
Joined: 10/13
Posted: 06/23/14 05:10 AM

the 89 EFI HO motor is not a PLUG AND PLAY in a 67 mustang.

you do have to create some connections.    did you get the matching computer...

do you still have the donor 89 mustang???? so you can remove more parts and the chassis side of the harness so you can unwrap it and just use the engine controls..
i ask because the 89 HO i seem to recall has Sequential port fuel injection where the injectors are fired 1 at a time in advance of the firiing order..  the firing order is also different..  the HO motor also in those years came with FORGED PISTONS..
the EFI motor without the HO.. came with batch fire fuel injection.. where four injectors at a time would fire.

for the fuel pump.. well.. you can duplicate that harness failrly easily..

here is the chassis side of the harness..

88Mustangefiharness Zpsd8a5c042

here is the engine side of the harness..

1995 Mustang 50Engineharness Zpsa2c34211

92 Mustang50ecmconnector Zpsbf55ea49

92Mustang50harness Zps9c383203

92 Mustangr50relays Zps9f96e3a1

92 Mustang50dashharnesstoengine Zps6b8bd958

Cp9115foreeciv KOEO Koertesting Zps6f1f70a0

this is an 87 SEFI wiring diagram.. it will be close... i will look around for an 89 version.

87 Mustang50efi EECIV Zpse31c6dd7

this is the other way.. the 91 to 93 diagram.. and how they hooked up the main and fuel pump relays..  i am almost sure the 89 versions were slightly different..

91 93 50 EEC4 Enginecontrolwiring Zps655c81e0

there are several articles around on this swap.. if you have not seen them..

you will also need depending on what you are going to do with it.. the vacuum switches and harness.   there are some issues about needing to pass the KOEO and KOER testing.. to get the best fuel economy so everthing has to work and be there .. including the air injection system..

are you using the original C4 transmission.. you will need the special flex plate to allow the use of your C4 behind the later 5.0..  they are fairly easy to put together..

if you are running the reverse rotation timing cover.. water pump and fan.. thats easily done also.. the wiring to the 3G alternator that came on 89 motors is different but fixable.  

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