Thinking about swapping in a automatic trans from a 4.6 police interceptor. Mmy question is can just swap everything over and go or do I need to tune the ecu for an auto? Any help would be appreciated
auto swap qiestion
- Thread starter seths99cobra
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i would think you would have to use a auto mach 1 ecu or get the auto mach 1 tune put on your ecu
You will need an auto ECU but there isn't one that is a direct fit for your car.
I'm not sure what (if any) the external differences are between the mustang GT (or mach) automatic transmission and the Crown Vic version are... but going with mach 1 parts sounds like the most logical place to start.
Assuming the external dimensions are the same, get a transmission crossover and a driveshaft from an auto GT (or mach). The ECU from a mach sounds like a good idea, but I have no idea how it's controlled... if there are any extra wires, pins, harnesses, etc. might be worth it to get a standalone controller.
One thing also worth noting. All the auto cars, even the Mach 1 4V's have 6 bolt cranks. I can't think of any factory 4.6 application where an 8 bolt flex plate was used from that time period, so you'll probably have to go aftermarket with that. (Actually, now that I think about it, all the 5.4 motors have 8 bolt cranks. You may be able to use a 5.4 flex plate from a truck or something.)
There have been many people who have done auto swaps in cobras... Hopefully they'll chime in to this thread.
Here's an idea. Autos have made big strides in efficiency the last decade or so... I wonder how hard it would be to swap in a 6 speed auto from a 2011+ Mustang GT. The bellhousing bolt pattern is the same. As a matter of fact, they might even have an 8 bolt flex plate. (youd need to do more research about that). But an afternarket standalone transmission computer is probably mandatory in this case.
The autos from the 2011 + coyote cars can handle some sick power, and have relatively low parasitic losses compared to older auto cars. The only thing is that they don't have quite as much aftermarket support as the older transmissions have.
If I ever did an auto swap, I think it would be one of those new 6 speed autos.... Or if ford ever does an automated manual transmission, (I'm gonna stop daydreaming now)
Assuming the external dimensions are the same, get a transmission crossover and a driveshaft from an auto GT (or mach). The ECU from a mach sounds like a good idea, but I have no idea how it's controlled... if there are any extra wires, pins, harnesses, etc. might be worth it to get a standalone controller.
One thing also worth noting. All the auto cars, even the Mach 1 4V's have 6 bolt cranks. I can't think of any factory 4.6 application where an 8 bolt flex plate was used from that time period, so you'll probably have to go aftermarket with that. (Actually, now that I think about it, all the 5.4 motors have 8 bolt cranks. You may be able to use a 5.4 flex plate from a truck or something.)
There have been many people who have done auto swaps in cobras... Hopefully they'll chime in to this thread.
Here's an idea. Autos have made big strides in efficiency the last decade or so... I wonder how hard it would be to swap in a 6 speed auto from a 2011+ Mustang GT. The bellhousing bolt pattern is the same. As a matter of fact, they might even have an 8 bolt flex plate. (youd need to do more research about that). But an afternarket standalone transmission computer is probably mandatory in this case.
The autos from the 2011 + coyote cars can handle some sick power, and have relatively low parasitic losses compared to older auto cars. The only thing is that they don't have quite as much aftermarket support as the older transmissions have.
If I ever did an auto swap, I think it would be one of those new 6 speed autos.... Or if ford ever does an automated manual transmission, (I'm gonna stop daydreaming now)
The external dimensions are the same. The 4r75 is a stronger transmission and it was was installed in 04s (mustangs, marauders and pssoible some other vehicles).
Regardless of which computer you use (GT or Mach), the harness will need to be repinned. So, there is no advantage to either one. Stand alone trans controllers are expensive and won't provide "stock like" reliability and drveability.
8 bolt flexplates are readily available as 5.4s and some 4.6 2Vs had 8 bolt cranks.
The 6r80 is a good, strong transmission but the rpm drop between first and second gear is huge so I don't recommend one for any engine that makes no low rpm tq. Stand alone controllers are available for this trans but they are quite expensive.
How much are you willing to spend on this swap?
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We (Maybe just me) are making this too complicated. I just found a very thorough article from Muscle Mustangs and Fast Fords Magazine where they did a 4R75W swap into an 03 Cobra.
All Pages: Ford Mustang Cobra Automatic Transmission Swap - Muscle Mustangs and Fast Fords Magazine
The article says there's a separate transmission harness consisting of 12 wires that must be repinned into the ECU. They ended up using the SYM2 Mach 1 ECU, but because the recipient car was an 03 Cobra, they had to do some extra mods to control the supercharger related stuff such as the intercooler pump and second IAT sensor, etc. controlled by the Cobra ECU but not the Mach ECU. You shouldnt have to worry about that.
This article has a complete parts list and is very thorough. Unfortunately, it doesn't show much of the harness or how to connect it. It just has one picture of the harness on the transmission before it is installed. I'm assuming it gets pinned directly to the ECU. But who knows.
At one point I was half tempted to swap in an automatic transmission into my 99 but then I thought it was probably a better idea for my next mustang..
Off topic, but I have dreams of building a Fox coupe from the wrecked remains of an automatic 2011+GT, Swapping out the whole firewall and floorpan as one piece so I can swap in the complete interior, not to mention the motor and 6r80 (thanks NaSVT) transmission.
All Pages: Ford Mustang Cobra Automatic Transmission Swap - Muscle Mustangs and Fast Fords Magazine
The article says there's a separate transmission harness consisting of 12 wires that must be repinned into the ECU. They ended up using the SYM2 Mach 1 ECU, but because the recipient car was an 03 Cobra, they had to do some extra mods to control the supercharger related stuff such as the intercooler pump and second IAT sensor, etc. controlled by the Cobra ECU but not the Mach ECU. You shouldnt have to worry about that.
This article has a complete parts list and is very thorough. Unfortunately, it doesn't show much of the harness or how to connect it. It just has one picture of the harness on the transmission before it is installed. I'm assuming it gets pinned directly to the ECU. But who knows.
At one point I was half tempted to swap in an automatic transmission into my 99 but then I thought it was probably a better idea for my next mustang..
Off topic, but I have dreams of building a Fox coupe from the wrecked remains of an automatic 2011+GT, Swapping out the whole firewall and floorpan as one piece so I can swap in the complete interior, not to mention the motor and 6r80 (thanks NaSVT) transmission.
^^ You have a manual valvebody and no converter lockup though so the computer doesnt do anything involving the trans. OP needs a computer to shift and lock the converter etc.
That's what I get for not reading... skimmed and saw auto swap so I piped in... fail
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