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3.8 to 4.6 Swap questions

Discussion in '1994-2004 V6 Mustang Tech' started by Redneck, Mar 24, 2020 at 4:45 AM.

  1. Redneck

    Redneck New Member

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    I'm new to this forum, just looking for some answers is there any good write ups out there on the 3.8L to 4.6L 2v swap? I currently have a 99 V6 5speed 134k miles on it, but just picked up a 2003 Mustang GT wrecked pretty good with 136k on it and lots of stuff done to it including rebuilt motor with cams, pistons and rods, new stage 2 clutch, ect all the goodies I picked it up for pretty cheap because I'm planning to do the swap my 99 has some sentimental value and I have a garage and lift and all the tools required just want to make sure I don't miss anything when I start swapping, I think we're just gonna drop the motor/ k frame on both cars and drop the body of my v6 onto the gt k frame / motor combo and put the trans in. Now the real questions I have is which wiring is all required the engine harness, engine to ecu harness, ecu, cluster. This is my summer daily so i'd like to be able to keep a/c and heat and all. Will the rad, condenser and fan from my v6 work with the gt? the gt front end is busted.
     
  2. 08'MustangDude

    08'MustangDude Profile Violation

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    You will need the GT Rad, it's not the same as the V6s. The hoses
    are not in the same positions. Not sure on the fan or condenser, as
    the compressor is not in the same spot either.

    Too bad you're front end won't swap on to the GT, you'd be better off.
     
  3. Edward S

    Edward S New Member

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    K Members are the same to my knowledge just the mounts interchange.
    Gt cooling parts.
    Swap the 8.8 rear while your at it, its a simple swap.
    Use the engine harness, ecu from the GT car, I don't know if the body harnesses are the same, sorry
     
  4. Redneck

    Redneck New Member

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    The side is also busted lol
     

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  5. Redneck

    Redneck New Member

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    I'm pretty sure the body harness is the same. I should just need the ecu and associated harnesses, cluster out of GT im just worried about having a pats issue lol
     
  6. Edward S

    Edward S New Member

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    Theres a company that can turn off PATS systems, you just mail him yours and he sends it back