Bare heads, machine work required?

Discussion in 'Engine Topic' started by tom3, May 29, 2021.

  1. tom3

    tom3 Veteran Member

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    Got a problem set of new heads, assembled, iron, need work. Local machine shop has closed, really a high quality shop with good people, going to miss that place. So I'm thinking about buying a pair of bare heads, swap the valves etc. from the new assembled heads in the bare castings. Question is are the valve guides, valve seats, etc. machined in a typical set of bare castings? Or do they require a lot of machine work?

    Edited, make more sense now?
     
    Last edited: May 29, 2021
  2. Rosster

    Rosster Veteran Member Gold Member

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    Huh?
     
  3. sooner

    sooner Veteran Member Lifetime Gold Member

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    The majority of budget bare heads can be assembled out of the box, with nothing required but a valve lap.

    Lots of other variables that we could talk about as far as preparation, but in the spirit of not muddying up the water...yes most can just be assembled.
     
  4. COPO

    COPO Veteran Member Lifetime Gold Member

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    LOL, Lots of work needed on store bought heads. Lots of junk out there.


     
    Last edited: May 29, 2021
  5. tom3

    tom3 Veteran Member

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    That's what I'm looking for. I can lap and do some minor port work. Thanks!
     
  6. sooner

    sooner Veteran Member Lifetime Gold Member

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    You may already have the +.100 valves in your iron heads, but if you end up needing some for the swap PM me. I have several sets of used SI stainless 2.02/1.6 valves laying around
     
  7. cadillac_al

    cadillac_al Veteran Member

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    I have seen my machinist spend a lot of time honing valve guides for that perfect clearance. I guess with CNC production that stuff isn't necessary anymore?
     
  8. tom3

    tom3 Veteran Member

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    If this was CNC work I'm not impressed. Your machinist is probably a rare perfectionist these days. Seems like just about everything is made half assed these days. summit heads rocker boss.jpg
     
  9. 1320feet

    1320feet Veteran Member

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    I don't understand why so many of the assembled heads are this bad, but they are. AFR are assholes for letting heads with .006 to .0085 run out leave there place.
     
    1980RS and sooner like this.
  10. sooner

    sooner Veteran Member Lifetime Gold Member

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    I have always suspected that the production tolerances for runout on mass produced heads are just way loose. I know no self respecting race shop would ever let a V/J go out the door in that kind of shape.
     

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