87-90 Mustang Turbo Swap Instructions Thanks go to
GT350R,
SVO1,
&
Crovax
- Authored by
140cilx,
Formatted and Re-worded by
Stinger
If you want a
printable checklist while you are doing the swap, left-click or
right-click/save-as here: Turbo Swap Instructions
1. Intro
This
is specific to the '87-90 LX cars receiving the '87-88 TC computer and VAM
harness.
These notes are for a 5speed car only, but should be close if you wanted
to do an auto trans conversion. (who would do that)?
First off try to use as many pieces as possible from an 87-88 Turbo Coupe,
as it will simplify the conversion process. You do not need the whole
wiring harness from the t-bird, only the VAM harness connector. DO NOT
remove the harness from the Mustang.
Read this article carefully and you should be set on how to wire the
conversion. if you do not understand something feel free to study that
area until you do understand. If you do not you could end up messing up
something that could be costly to repair.
Also feel free to email me with any questions, or if you find any errors
in this article. I will not accept responsibility for anything you might
fry in the process of doing this swap. I advise researching all the wiring
diagrams and EEC IV info you can get your hands on.
I am not going to explain how to remove and install pins from a connector,
if you can't figure it out you might not want to do this swap. I will
give you a hint though, a small screwdriver or small razor knife works
well.
2. How
to Connect VAM Wiring
From the VAM wiring
harness from the Turbocoupe:
Connect the 5v reference (orange/white) VAM harness wire to the wire going to pin 26 of the stock
harness (also orange/white). When I say connect I mean cut the
connection, disregard the former wire running into the engine bay, and
connect the new wire. This wire going to pin 26 can be found at your EGR
plug. This means you will no longer use your EGR.
Connect the VAF (white/black) VAM harness wire to the wire going to pin 27 of the stock
harness (brown/light green). (This wire going to pin 27 can be found
at your EGR plug. This means you will no longer use your EGR.)
Note: Remove unused ECU pin 3 from Mustang wire harness ecu plug (or
take one from your TC harness you salvaged) and put this pin/wire into the
ecu plug of your Mustang harness at position 43.
Connect the VAT (light green/purple) wire from the VAM harness to Pin 43.
So now the wire at position 43 should go from the ecu to the VAM
harness.
Note II: Splice into/"T" connect the VAM harness signal return (black/white) wire
into the LX harness (black/white) wire that goes to pin 46. Do not cut
the LX harness (black/white) wire going into pin 46, simply connect this
VAM signal return black/white wire to it.
The end result should be the wire going from ecu position 46 and then
branching off to a number of sensors including the VAM, not just to the
VAM exclusively.
3. ACT
Wire Conversion
no changes necessary.
Connect ACT wire to the wire going to pin 25 (green/red). This is a plug
in on the ’87-90 LX cars using the ’87-88 TC computer since we have an ACT
sensor.
4.
Premium Mode Wiring
Cut the wire going into pin 24 of the LX harness about 5” above the
wiring block. This is an Air Conditioning Wire. The Air Conditioning will
still work properly with this wire cut and capped – this was an idle
increase control wire for the A/C. The 5” section of wire remaining,
going into the computer is your pin 24 octane control. Take this wire and “T”
this into pin 46 (signal return). This will complete the connection and
allow your computer to run in the “High Octane” setting. You must from
this point on, run 91 or greater octane fuel.
5.
Closing
Unplug the vacuum
hose going to your MAP sensor and leave it unplugged on the MAP, Then cap
the vacuum tree port where the vacuum line plugged into the vacuum tree.
The above information does not include wiring in the Electronic (computer)
Boost Control, so you will need to add a preferred (for greater boost)
adjustable boost valve, ignoring computer control of boost. I prefer the
Gillis valve found at www.boostvalve.com.
You
should use the Mustang injector harness. The TC harness has some
more wires integrated into it and complicates the swap. Make sure
you use the TC injectors though. They are not interchangeable.
6. Helpful Info:
Step-by-Step Swap Turbo Swap Instructions can be
found
HERE
