4v heads on a 2v motor?

Discussion in '96-04 - 4V Specific' started by joshuaw3, May 5, 2015.

  1. joshuaw3

    joshuaw3 Active Member

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    I have a 98 gt with the stock 4.6 2v in it and I was wondering if I could swap 4v heads on it from 03 Mach 1/ cobra. Will that work or not?
     
  2. 96blak54

    96blak54 Legend

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    Yes it will work! Source the intake, front cover, valve covers for plug wires, fuel rails, cobra alternator(cause a thick old Gt alt wont fit the intake,...its gotta be a thin cobra alt) exhaust logs. Should work real good....now go get it all and swap. We're here to help out, so post lots of questions and post lots of pictures of your swap.
     
  3. joshuaw3

    joshuaw3 Active Member

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    Well here's the thing I found a guy locally who says he has a 4v 93 mark viii motor with 03 navigator heads which are the same as the Mach 1 and cobra heads so should I just get the whole motor and swap it or just do the heads? And where would I get all that stuff you said I need? If I swapped the motor what would I do about the computer do i need a new one or will it work just fine with a tune?
     
  4. 96blak54

    96blak54 Legend

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    The navigator heads are navigator heads ...and the mach1/cobra are cobra heads. If the heads are in fact navigator heads they will still work but will have low torque reproduction compared to any other head, assuming a normal intake will be used.
    Sourcing the other parts from junkyards or classifieds works
     
  5. ft_nox

    ft_nox New Member

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    Just being nosey.. would he need a new computer or a tune to make the most of the swap? Also, could aftermarket rails be used?
     
  6. 96blak54

    96blak54 Legend

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    Key word here is "most". It'll run with out the tune with all the gt hookups, but to gain the most a dyno tune is a must.
     
  7. punched281

    punched281 Active Member

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    Don't forget about timing chain shtuffff
     
  8. 96blak54

    96blak54 Legend

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    Good point. The heads should come along with its original cam timing chains. And your 2v chains will work also
     
  9. 03DSGGT

    03DSGGT SN95 Supporting Member

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    Won't just swapping the heads kill the compression? I thought the 4V cars have -3cc piston dish compared to the NPIs -10.5cc....
     
  10. 96blak54

    96blak54 Legend

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    Youre right, but we was just answering OP question
     
  11. 03DSGGT

    03DSGGT SN95 Supporting Member

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    Ah I gotcha
     
  12. punched281

    punched281 Active Member

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    Maybe he will boost the hell outta it