Terminator engine swap into 03 GT

Sluggie24

Active Member
Established Member
Joined
Jan 12, 2017
Messages
277
I just purchased an 04 terminator complete engine (pan to blower, accessories, harnesses) that I'm going to rebuild and then swap into my sons 03 GT auto but have a few questions.

Since his car is auto I'm going to have to use his engine/trans harness and PCM. I know I have to extend the coil wires for the harness to work and I have the termi engine harness that I can use to splice on the longer coil wires. Is there other wiring modifications I would have to do?
 

StrayBullitt

Well-Known Member
Established Member
Joined
Aug 16, 2016
Messages
1,213
Location
Seattle (GO HAWKS!)
I gonna have to say there are going to be some inputs you will be missing and are probably going to need to account for in some way. You won't have knock sensors function, so you'll probably want to tune conservative. Also down stream intake air temps, assuming you will need to swap over plugs and pin out the Alternator correctly, you'll need to power up an intercooler pump and set all that up somehow. Just a couple things that come to mind.
 

Sluggie24

Active Member
Established Member
Joined
Jan 12, 2017
Messages
277
I understand about the boost/charge temp sensor. No way to wire that in since the gt pcm never used it. I think there is a stand alone knock sensor system I can get and wire into the pcm. I think with the alternator i might just have to switch 2 wires around like the coils?

For the intercooler pump i was thinking i can just wire in a relay that will activate with key on or engine running.

I think i also have to bypass the boost bleed solenoid and just plug the actuator into a vacuum port on the back of the blower.
 

decipha

Well-Known Member
Established Member
Joined
Jul 12, 2008
Messages
1,024
Location
New Orleans, LA
You will need to unpin the connector for the coils and flip the wires around. 4v coils are reverse polarity compared to the 2v coils. Same goes for the alternator just swap the wires around. The middle wire isn't needed if you have one. If you have the cobra alternator connector you will see the wires are swapped just simply keep the wiring colors the same.

You will need to cut the wires going to the iat sensor and extend and run them to the iat2 sensor. That's the sensor at the back of the lower intake.

You are correct. The bypass actuator gets hooked up to manifold vac. The boost bypass solenoid is not used.

Most people hook up the intercooler pump relay so it comes on with key on / ignition.

I highly recommend keeping the knock sensor when tuned and dialed in properly the knock sensors work excellent. You can file down the boss and the manifold to keep the knock sensor mounted in there. Check out the mercurymarder.net forum there is a write up which describes how to keep the knock sensor.

There is no other wiring modifications needed. The GT ecu is the same as the cobra all inputs are accounted for.

As far as tuning goes the best tune you can run for your setup is a stock 03/04 cobra automatic tune. Your probably thinking to yourself no such thing exists right? Not quite. There was an unreleased 03/04 cobra automatic tune that ford never put in to production. As far as I know i'm the only person that has it. Its the same base tune I use for all the 2002-2004 automatic GT's I tune as well and it works beyond exceptionally well.
 

Sluggie24

Active Member
Established Member
Joined
Jan 12, 2017
Messages
277
That's a bunch of great info. Is it possible to just use the cobra harness in a gt?
 

decipha

Well-Known Member
Established Member
Joined
Jul 12, 2008
Messages
1,024
Location
New Orleans, LA
no he cannot since hes running an automatic

you should never swap a cobra harness in to a gt when doing a cobra swap its significantly more time consuming and doesn't solve anything.
 

Sluggie24

Active Member
Established Member
Joined
Jan 12, 2017
Messages
277
Ok that is what I thought. Easier to just modify the gt harness. Thank you very much!
 

Users who are viewing this thread



Top