69 Heads.... Replace/rebuild?

Discussion in '1965 - 1973 Classic Mustangs -General/Talk-' started by Andrew Toolen, Nov 4, 2013.


  1. Andrew Toolen

    Andrew Toolen New Member

    Joined:
    Nov 4, 2013
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    2
    Location:
    STL
    Need some help....
    I have a stock 69 Grande and am about to do some upgrades!
    Motor is all stock except for the heads that were put on before I bought it.... It had stock 2V heads, and they put on 4V heads.... Still technically needs lead additive, I havent used it..... Ive had her for about a year now and ready to do some work!
    Have a Holley 600, Edlebrock Intake, and since I am doing that I figured its time for new heads and cam....

    Not sure what heads are on there now... Only marks when I take the covers off are in the pic, anyone know what heads they are?
    Are they better than the Gt-40 heads...

    Thanks!!!
    Andrew
     

    Attached Files:

    #1
  2. rbohm

    rbohm Founding Member

    Joined:
    Apr 13, 2002
    Messages:
    6,337
    Likes Received:
    259
    Trophy Points:
    124
    Location:
    tucson,az
    is this a windsor or cleveland engine? if a windsor there is no such thing as a specific 4v head, like there is with the cleveland. also the heads you have in the picture are a D8 head meaning it was a part released for production in 1978, which means they are set up with hardened valve seats for unleaded fuel. by the way, since it is a D8 head its not a cleveland head.

    now if the heads are in good shape, then run then, unless you want better performance, in which case you want a better head. the GT40 heads are good, but there are better heads on the aftermarket depending on what you want this motor to do.
     
    #2
  3. Andrew Toolen

    Andrew Toolen New Member

    Joined:
    Nov 4, 2013
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    2
    Location:
    STL
    Oh ya she runs great, just want to wake her up a bit... I think that will happen with the headers, and going from a 2 barrel carb and intake to a 4 barrel carb and intake!
    78.... Kid told me he put 70 heads on.... Better or worse? Not wanting to go wild with the motor, just want to make sure I dont want to redo things next year....
     
    #3
  4. rbohm

    rbohm Founding Member

    Joined:
    Apr 13, 2002
    Messages:
    6,337
    Likes Received:
    259
    Trophy Points:
    124
    Location:
    tucson,az
    the only real difference between the 70 and the 78 head is going to be the combustion chamber size, the 78 head i believe is 64cc while the 70 head is closer to 54cc, which means a big gain in compression ratio with the smaller chamber, going from about 8:1 to around 10:1 roughly.
     
    #4
  5. Andrew Toolen

    Andrew Toolen New Member

    Joined:
    Nov 4, 2013
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    2
    Location:
    STL
    SO you think I should put a set of GT-40 heads on?
     
    #5
  6. rbohm

    rbohm Founding Member

    Joined:
    Apr 13, 2002
    Messages:
    6,337
    Likes Received:
    259
    Trophy Points:
    124
    Location:
    tucson,az
    the GT40 heads are good ones to use for a budget build. just remember that there are GT40 and GT40p heads. avoid the P heads as they have a revised plug location that requires different headers. you can tell because the plugs are not angled like the regular heads are.
     
    #6
  7. Andrew Toolen

    Andrew Toolen New Member

    Joined:
    Nov 4, 2013
    Messages:
    5
    Likes Received:
    0
    Trophy Points:
    2
    Location:
    STL
    Thanks for the help!!
     
    #7
  8. rbohm

    rbohm Founding Member

    Joined:
    Apr 13, 2002
    Messages:
    6,337
    Likes Received:
    259
    Trophy Points:
    124
    Location:
    tucson,az
    anytime
     
    #8

Share This Page