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Discussion Starter #1
hi i am getting a p code focus with the sohc motor. Since these motors are so freaking expensive, i was considering swapping to a dohc 3 code motor. how difficult is this and what would i all need to do it? i am assuming computer and wiring harness from the motor.....is the tranny and other motor accessories the same? will the guages work right with the new sensors?

basically i just need to know what i need to make this work if its even possible

thanks
josh
 

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Aurelius Pardus
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^^ well lucky me someone found this link for this site, then I found this, and it tells you everything you need for the SPI (SOHC, P code) conversion to the Zetec (DOHC, 3 code) engine [thumb]

http://www.modifiedfocus.com/spitozetec.htm

if you know how to do it, then you should have no problem. just one note, if it's a manual, the current transmission will not mate up to the engine, so factor that in too. if it's an automatic, however, then you're all set to go [thumb]

hope that helps [:)]
 

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Aurelius Pardus
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and to answer the other questions........ from what I've heard, it's a fairly easy conversion. yes, you need the wiring harness for the engine, and also the ECU. and yes, the gauge works as well, but I'd recommend finding one with a tach if you really need it, cause the SPI's don't come with tachs. like I said, auto trannies are the same, if it's a manual, you're gonna have to get an MTX-75, or if you really want to, the Getrag 6-speed found on the focus SVT.

transmission (or driver's side, whatever you call it [hihi]) and the lower engine mounts are the same...... as for the passenger side, it's probably gonna have to be a custom mount, or the Zetec mount...not sure on that one. whatever it is, you'll need a different pass. side mount [thumb]. that should be it as far as I can think of..
 

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Aurelius Pardus
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oh.........right. also like it said, the PATS (passive anti theft system) will need to be reset in order to let you drive your car. so it's either get the keys from the car the zetec came from, or take it to ford and have them reprogram it [:p]
 

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Discussion Starter #5
so anyone know how much it costs to flash the computer for pats? also which computer will i need then? i am assuming the one for a dohc automatic? as far as the exhaust, will i just need the piece between the manifold and the cat or is it completely different? how many wires go back to the fuel pump? could a person just splice in the engine harness or do i have to switch out the whole wiring running to the pump?
 

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Discussion Starter #6
did some research, a/c pumps are the same as well as the starters. alternators and power steering pumps are different though. does anyone know the difference between the raised seam runner engine and the smooth seam runner?
 

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ok

never done this one but I just finished an automatic zetec to manual svt swap and I had to change engine wiring harnesses and the harness under the dash. it was a pain but well worth it. I still have everything from the swap if you need parts. as far as splicing the wires I am not sure if the engine wiring harnesses are the same. I spliced mine together going to the fuel pump. I am unsure of the differences between the zetec and spi wiring though so I can't say either way
 

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Discussion Starter #9
you've got mail.......anyways, i am pretty sure i have to swap the engine harness itself, hopefully the rest of the underhood wiring is the same. Found out that the mass air meter is also the same. To clear up the pats thing, once i get a computer i will have to take it in and have it flashed to match my car? do i need any info from my car or do they basically just reset the computer and it will reprogram itself to my keys and stuff? also, anyone know if the exhaust is the same from the cat back? can i just use a zetec downpipe and connect it to the spi exhaust? Will i have to modify the fuel lines under the hood?
 

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i would...

i would make a how to but it was one of those things i just done. got a real good deal on the front half of a wrecked svt and the auto was going out again. i had to change the computer, axles, ignition cylinders( i didnt have to but that way i didnt have to have the computer reprogrammed) all the wiring under the dash, all wiring under the hood, the pats system, the antenna for the pats stystem. you need the sensors for the clutch pedal. it was pretty straight forward for the most part. some wires had to be spliced back to the fuel pump because the car i got was cut. thanks for the congrats though.
 

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Discussion Starter #11
if i match the keys to the computer, do ii still have to have compuetr flashed? junkyards said it needs to be programmed to match the vin or something stupid
 

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Discussion Starter #12
b4 i forget....which computer should i be looking for? there are like 20 different ones will any dohc auto computer work?
 

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My local dealership says $89 for the pats flash........also said he's never heard of having to flash a focus. Just passing along the info I'm finding as I do my engine swap :)
 
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