87-88 Turbo Coupe Motor Swap for 88-90 4cyl Mustangs

This is written specifically for installing a 87-88 Turbo Coupe motor in a 88-90 4cyl Mustang. Check the "Turbo Resources and Conversion Web Sites" section below for turbo swap info related to other year Mustangs. This conversion requires a complete 87-88 Turbo Coupe motor with turbo, turbo computer, vane air meter, EEC harness or at least the vane air meter harness and optional intercooler. 

Reference Documents:

Turbo Resources and Conversion Web Sites = List of 2.3l Turbo resources I used for my Turbo conversion.

Turbo 101 = Document covers the basics on how a turbo works and the functions of other turbo related items such as the waste-gate, boost controller, blow off valve and intercooler. Also contains information on other sensors and devices pertaining to the 2.3 EFI engine.

Post Turbo Swap 88-90 Mustang Sensor Location  = Post turbo swap sensor location diagram

88-90 Mustang Production Wire Diagram = Production EEC wiring diagram for 88-90 2.3L Mustangs

87-88 Turbo Coupe Production Wiring Diagram = Production EEC wiring diagram for 87-88 2.3L Turbo Coupes

Turbo Conversion EEC Wiring Diagram 88-90  = Post turbo swap EEC wiring diagram showing the modifications

Post Turbo Conversion 88-90 Mustang Vacuum Diagram (Stock Boost Controller) = Post turbo swap vacuum diagram using stock boost controller valve.

Post Turbo Conversion 88-90 Mustang Vacuum Diagram (RIC Gillis Boost Controller) = Post Turbo swap vacuum diagram using a RIC Gillis boost controller valve.

EEC Pin Out = Pin out chart comparing each EEC pin and it's function between the stock 87-90 Mustang and Turbo computers.

Turbo Motor Parts for Turbo Conversion:

• LA, LA2 or LA3  EEC computer for 5-Speed cars

• LB1, LB2 or 8UA EEC computer for Automatic cars

• Large Vane Air Meter w/Harness & 35# Injectors

• 2.3l Turbo Coupe Motor

• IHI, T3 or T3/TO4E Hybrid Turbo

Mustang 2.3l Motor Parts needed for New Turbo Motor:

• 87-90 2.3l Mustang Injector Wiring Harness

• 87-90 2.3l Mustang Upper and Lower Intake Manifolds w/Sensors

• 87-90 2.3l Mustang Throttle Body

• 87-90 2.3l Mustang Oil Pan

• 87-90 2.3l Mustang MAP Sensor

Other Recommended Parts for Turbo Conversion:

• K&N Filter - RE-0930, Jegs part number = 599-RE-0930 = 3" by 6" long filter that mounts to VAM
• Walsh Racing Adjustable Cam Pulley = Allows for degree changes in the camshaft timing

• Ric Gillis Boost Control Valve = Manual adjustable boost controller valve

• Volvo 760 Intercooler and 93 Ranger V6 4.0 Radiator = Front mount intercooler and radiator

• Bailey EVO Blow Off Valve = Good dual stage blow-off valve

• Walboro 190/255lb Fuel Pump = Good upgrade fuel pump

Gasket and Sensor Part numbers:

• Valve Cover Gasket = Felpro VS50043R1 or Ford F57Z-6584-A

• Intake Gasket = Felpro MS92424

• Exhaust Gasket = Felpro MS90266-1

• Oil Pan Gasket = Felpro OS34211R

• Head Gasket = Felpro 1035
• Intake Valve Stem Seals = Intake Valve Seals E7ZZ-6571-A
• Exhaust Valve Stem Seals = Exhaust Valve Seals E7ZZ-6571-B

• Rear Engine Seal = Felpro

• Timing Belt = Gates T014

• PCV Valve = Ford EV127-A

• Plugs = Motorcraft AWSF22C or NGK TR5

• Thermostat = STA-13829

• Thermostat Gasket = Felpro 35114

• Oil Filter = FL300

• Oil = Pennzoil 10W30

Turbo Coupe Motor Swap Guide:

1. Disconnect the Battery!

2. Removing the old motor.

3. Remove the oil pan, throttle body, injector harness, upper and lower intakes from the old motor and use them on the Turbo Coupe motor. This will ensure all sensor wires will reach and no extra vacuum ports will need to be plugged.

4. Locate the Map sensor next to the vacuum tree on the firewall.

5. Remove the vacuum line from the MAP sensor to the vacuum tree on the firewall. Plug it at the vacuum tree only. Do not plug the vacuum line port on the MAP sensor.

6. If using a used turbo motor it is recommended that you either rebuild it or perform a seal-n-shine which is basically a cleaning, new seals, gaskets and paint. Install the original Mustang oil pan, throttle body , injector harness and intake manifolds when assembling the engine. Use the turbo motor EGR valve in place of the Mustang EGR valve.

7. Install the Turbo Coupe engine and re-connect everything.

8. If using the stock Boost Controller valve, route the vacuum line system as shown in my turbo vacuum diagram. If you will be using the Ric Gillis Boost Control Valve follow this turbo vacuum diagram.

9. Install the turbo motor computer and follow my wiring procedures to finalize the installation of the turbo motor.

Turbo Swap Wiring Instructions 88-90 Mustang:

Note: You will see pin wire 46 mentioned throughout the steps below. This pin wire should never be removed or cut out. When instructed to T-in or splice into this wire simple connect the new wire to this existing wire using a piggy-back connector or similar connection. Several sensor share this wire to send signals back to the computer. The computer knows which sensor is sending the signal by the signal the sensor sends. Cutting the wire out will result in some sensors not being able to report back to the computer.

Map Sensor = The Turbo Coupe motor uses a BAP sensor (Barometric Absolute Pressure) to make corrections to the fuel and timing tables based on different altitudes, the Mustang uses a MAP sensor (Manifold Absolute Pressure) to perform this same function. The MAP sensor will work with the Turbo Coupe motor by simply unhooking the vacuum line that runs from the sensor to the manifold or vacuum tree. Thus allowing the MAP sensor to read outside barometric pressure instead of manifold pressure. Do not plug the MAP sensor vacuum port on the MAP sensor itself, only the manifold or vacuum tree port. Leaving the MAP sensor vacuum port open allows the sensor to read the outside barometric pressure instead of the manifold pressure it would normally if connected to the vacuum source on the manifold.
 

VAM Meter = The Turbo Coupe motor uses a Vane Air Meter (VAM) to calculate the amount of air entering the motor. The stock Mustang motor does not have VAM Meter. You will be using three of the wires that used to go to the EGR position sensor to connect the VAM. Click here for a diagram of the VAM Meter connections.

• Locate the EGR position sensor plug (3 Wires - Orange/White, Black/White, Brown/Lt-Green) on the Mustang EEC engine bay harness.

• Cut the Orange w/White stripe wire (Pin Wire 26) from the EGR position plug and connect it to the VRef (Orange w/White stripe) wire from the VAM harness.

• Cut the Brown w/Light Green stripe wire (Pin Wire 27) from the EGR position plug and connect it to the VAF (White w/Black Stripe) wire from the VAM harness.

• Cut the Black w/White stripe wire (Pin Wire 46) from the EGR position plug and connect it to the VAM Signal Return (Black w/White stripe) wire from the VAM harness.

• Move the Dark Green wire (Pin Wire 33) from the EGR Vent Solenoid on the Mustang Computer plug to pin 43.

• Locate the EGR vent solenoid plug (2 Wires - Red and Dark Green) in the engine bay and cut them from the EGR Vent sensor plug. Connect the Dark Green wire (Now Pin Wire 43) to the Vane Air Temp (Light Green/Purple) wire. Cap off remaining red wire to EGR Vent Solenoid.
   

EGR Control Valve = Although all of the other Turbo conversion web sites for Mustangs state to disable or remove the EGR. I suggest re-pinning the wires on the EEC, using the stock Turbo Coupe EGR valve and hooking up the EGR as it was on the Turbo Coupe motor originally. The Turbo Coupe EGR sensor only needs one sensor hooked up (EGR Control) as opposed to the Mustang EGR system which uses three sensors (EGR Vent, EGR Control, EGR Position). You will basically be dumping two of the sensors (EGR Vent , EGR Position) which the Turbo Coupe computer does not have provisions for anyway. Click here for a diagram of the EGR Control Solenoid connection. This step can be omitted if you wish not to use the EGR control solenoid.

• Move EGR Control Solenoid (Pin Wire 52) Yellow wire to pin 33 on the Mustang computer harness plug.

Premium Fuel Switch = The Turbo Coupe computer has a provision for a premium fuel switch which allows the driver to use different timing and fuel curves depending on the octane rating of the fuel being used. Most will say to just wire this so that it is always in premium mode but I like the advantage of being able to run lower octane fuel if I choose. Click here for a diagram on wiring in a premium fuel switch.

• Mount a toggle switch or equivalent switch some where on or in the dash or console.

• Locate the Green w/Purple stripe wire (Pin Wire 24) at the computer. This is the AC idle adjustment wire which is triggered off the AC system. Cut the wire from the computer plug about 5 inches up. Cap end of the wire left in the harness as to not short anything. The signal for this wires comes from the AC not the computer.

• Connect a new wire onto the 5" wire at the computer harness plug and run it to one side of the switch you installed.

• Run a new wire from the other side of the toggle switch and connect it to (Pin Wire 46) Black w/White stripe on the Mustang computer harness. Note: Do not cut pin wire 46, simply T-in or splice in the new wire.

Note: If you wish to connect the Premium fuel switch so that it is always set "On" simply run connect the end of the 5" wire to Pin Wire 46. Make sure you t-in or splice into pin wire 46, do not cut or remove pin wire 46.

Optional Stock Electronic Boost Controller = The Turbo Coupe computer is equipped with a electronic boost controller valve. It is recommended that you upgrade to a manual boost value for higher boost pressure but if you wish to retain the stock electronic boost controller valve follow the below instructions.

• Run the Pink w/Black stripe wire from the boost controller valve to Pin wire 31.

• Splice in the Red wire from the boost controller valve to pin wires 37 and/or 57. This is the Red wire that was capped off  when hooking up the VAM meter which was from the EGR vent solenoid. Do not remove pin wire 37 or 57. T-in or splice in to the existing connection.