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4.0 Heads

Discussion in 'Intermediate CJ-5/6/7/8' started by Coloradocj5, Aug 18, 2008.

  1. Coloradocj5

    Coloradocj5 New Member

    I know the 7120 head is the best for the 4.0 liter conversion, but I'm seeing some 0630 heads advertised as HO heads . Are these as good as the 7120's for the 4.0 swap? Or can you tell me the difference.

    Thanks in advance
     
    Coloradocj5, Aug 18, 2008
    #1
  2. nsargeant

    nsargeant New Member

    they are the same head but the 7120 is supposed to have the temp sensor already drilled and tapped in the rear of the head. Other then that I think they are the same. I have an 0630 but it had the temp port in back. Can't figure that one out

    nathan
     
    nsargeant, Aug 18, 2008
    #2
  3. Boodie

    Boodie Boodie

    Hey Phil,

    I too have noticed that more and more people have used the 0630 head. I can only assume that it's just not that much of a noticeable difference for what we are using it for. It's not like we are building Street Drag cars! Maybe someone will chime in with their 2 cents and let us know if they are getting 15-20% better gas mileage with the 0630 heads.

    Did you start your build yet?

    ~Greg

    R)
     
    Boodie, Oct 7, 2008
    #3
  4. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    I recall there are some WJ heads with smaller valves that you want to avoid - read that on www.jeepstrokers.com somewhere - can't find it now.
     
    timgr, Oct 7, 2008
    #4
  5. Hansh

    Hansh Going Mobile

    CJOffroad forum has a whole section dedicated to the 4.0 swap. There is a lot of good info there.
     
    Hansh, Oct 8, 2008
    #5