Step by Step guide to installing a Mark VIII motor in a 96+ GT.
Thread Starter
4th Gear Member
Joined: May 2009
Posts: 1,925
From: DFW, TX
Quite a bit. basically went from a 6.3 second 0-60 to a 5.7 with decent traction and nearly a second off from my 0-80MPH. I am sure that when I get it tuned I will pick up even more power.
2V before:
http://www.youtube.com/watch?v=aWYQyjfkJnI
4V after.
http://www.youtube.com/watch?v=nlrNOs8Qnro
2V before:
http://www.youtube.com/watch?v=aWYQyjfkJnI
4V after.
http://www.youtube.com/watch?v=nlrNOs8Qnro
1st Gear Member
Joined: Feb 2010
Posts: 69
From: la
how long did your project take after everything done for the swap?
Chupacabra
Joined: Jul 2004
Posts: 9,621
From: wilkes-barre PA
Id like to add a little side note, im not sure if you checked this out or not. When i first did my 97 cobra 4v swap in my gt, I re-used the GT computer and it ran fine and i had no problems at all. When I put the car on the dyno a month or two later the car only made 190rwhp. The guys at SGS pointed to my attention that the 97 GT computer did not have the parameters in it for the IMRC plates and in turn they did not open. The only fix was to either delete the IMRC or use a cobra ECU. I opted for the deletes.
Thread Starter
4th Gear Member
Joined: May 2009
Posts: 1,925
From: DFW, TX
The GT tune wont allow it. The A/F ratio just 0's out at 6K RPM and you loose all power. Scared the crap out of me when I discovered it.
From the day I pulled it to the day it was road worthy, 19 days. That included pulling the old engine on Tuesday, waiting till till that weekend to go to the pick U pull, then finding the exhaust manifolds and waiting on them to ship my throttle cable, then assembly and install. I would say 3 days of actual work if you had all of the parts that you needed. A day to pull it, a half day to assemble, and a full day and a half to install.
I didn't use the IMRC's. I loose some low end grunt, but it's not that bad really. It starts screaming at 3K RPM. I addressed if you wanted to keep the IMRC plates, you would have to use an RPM window switch and a set of relays to activate and deactivate the motor. Much like a Nitrous setup.
Id like to add a little side note, im not sure if you checked this out or not. When i first did my 97 cobra 4v swap in my gt, I re-used the GT computer and it ran fine and i had no problems at all. When I put the car on the dyno a month or two later the car only made 190rwhp. The guys at SGS pointed to my attention that the 97 GT computer did not have the parameters in it for the IMRC plates and in turn they did not open. The only fix was to either delete the IMRC or use a cobra ECU. I opted for the deletes.
3rd Gear Member
Joined: Jul 2009
Posts: 875
From: California
The GT tune wont allow it. The A/F ratio just 0's out at 6K RPM and you loose all power. Scared the crap out of me when I discovered it.
From the day I pulled it to the day it was road worthy, 19 days. That included pulling the old engine on Tuesday, waiting till till that weekend to go to the pick U pull, then finding the exhaust manifolds and waiting on them to ship my throttle cable, then assembly and install. I would say 3 days of actual work if you had all of the parts that you needed. A day to pull it, a half day to assemble, and a full day and a half to install.
I didn't use the IMRC's. I loose some low end grunt, but it's not that bad really. It starts screaming at 3K RPM. I addressed if you wanted to keep the IMRC plates, you would have to use an RPM window switch and a set of relays to activate and deactivate the motor. Much like a Nitrous setup.
From the day I pulled it to the day it was road worthy, 19 days. That included pulling the old engine on Tuesday, waiting till till that weekend to go to the pick U pull, then finding the exhaust manifolds and waiting on them to ship my throttle cable, then assembly and install. I would say 3 days of actual work if you had all of the parts that you needed. A day to pull it, a half day to assemble, and a full day and a half to install.
I didn't use the IMRC's. I loose some low end grunt, but it's not that bad really. It starts screaming at 3K RPM. I addressed if you wanted to keep the IMRC plates, you would have to use an RPM window switch and a set of relays to activate and deactivate the motor. Much like a Nitrous setup.
I swapped out my NPI gt to a PI04gt motor and still have the NPI gt tune. Now, I have the 04gt ecu but idk if I can simply switch it out. Which is why I ask if you can do the same, put a cobra ecu on your car.
Last edited by nascrchi; Feb 11, 2010 at 06:14 PM.
Thread Starter
4th Gear Member
Joined: May 2009
Posts: 1,925
From: DFW, TX
so that should be in the "what you will need" section right- the ecu? I just doesn't make sense that a motor that can revv up to about 7k only b revved at 5800 or so. Do you plan on changin the ecu? To be honest, I don't really know what I'm talkin about but help me out.
I swapped out my NPI gt to a PI04gt motor and still have the NPI gt tune. Now, I have the 04gt ecu but idk if I can simply switch it out. Which is why I ask if you can do the same, put a cobra ecu on your car.
I swapped out my NPI gt to a PI04gt motor and still have the NPI gt tune. Now, I have the 04gt ecu but idk if I can simply switch it out. Which is why I ask if you can do the same, put a cobra ecu on your car.
3rd Gear Member
Joined: Jul 2009
Posts: 875
From: California
