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small diameter solid back balancer on 76 350 ?

Discussion in 'The Garage' started by R72K5, Jan 9, 2005.

  1. R72K5

    R72K5 Banned

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    small diameter solid back balancer on 74 350 ?

    ok this 74 350 engine i put in the 84, the crank dampner is one of those old orange red 6 1/4" ones like the old 307s and such had, well i was feeling around it and the backside is solid closed up not open like they always are, i thought only 400s and 454s got solid balancers ? i always assumed this one was a regular old 350 small diameter open back dampner, but its not, but it is factory stock painted one

    the block is stamped CMJ and it just has those 882 heads on it, its painted stock chevy orange red still, old


    how big diameter were the 400 sbc balancers ?

    hummm

    thanks
     
    Last edited: Jan 9, 2005
  2. R72K5

    R72K5 Banned

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    ok its a '74 full size police 350 4bbl, humm.


    maybe police package balancer ?

    dunno

    i give.,.

    its older engine than i thought, damn, but runs good, so thats cool



    thanks
     
  3. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Sounds like it is an early 350 balancer. ALL SBC 400's have an 8" balancer with a counter weight on the back side.
     
  4. R72K5

    R72K5 Banned

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    i just never knew there were any solid back 350 dampners then, the only dampners i ever have seen on 69-early 70s 350s were the 8"hollow ones, ive had many early 70s 350s never seen or heard of or ever seen a 6.25" one on any before, especially on a 4 bbl one, hmm..



    why would there be a need for a solid dampner ?

    i know that the backside of the 400 balancers have a spot where metal is removed though, i didnt feel such thing on back of this one, i felt most of the way around but not the top part,

    hmm

    im gonna put on an 8" open back from later 70s 350 truck engine

    unless i can find out more about these earlier small ones ?

    no 350s were externally balanced at all right ??

    what i always been told


    thanks
     
  5. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    The only SBC that is externally balanced is the 400, that is up until the event of the 1 piece rear main seal engine in 1986 then those are externally balanced ONLY on the rear not the front.
     
  6. R72K5

    R72K5 Banned

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    really ?

    ill be damned

    so 86 up all are balanced flexplates flywheels ??
    i thought they only changed rear mains and oil pans in 86


    for real ?

    damn

    ok so (non-400 and 454) dampners were all neutral balance correct ?
    and flywheels flxplates also- til 86 ?

    right ?

    hmmmmm


    im starting to wonder if i really want to keep this 74 350 or not, i dont like 882 heads and im not too sure about this dampner setup on it,
    i think im gonna look for a later engine and scrap this one out, i gotta pull the tranny anyways and swap in the th350, so,,,



    thanks
     
  7. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    That would be correct. SBC were all the same as far as balancing was concerned except for the 400 up until 1985. 1986 GM changed to a 1 piece rear main seal and externally balanced on the back end only. Starting in 1987 GM made another change to center bolt valve covers, different intake bolt angle on the center 2 bolts, and the addition of roller cams for cars but not trucks. Once again GM made a change in 1996 when they came out with the vortec which had different heads and intake. Somewhere in the middle of all this GM also had the LT-1 and LT-4 which had some differences as well. I'm not sure which had what but one has a reverse coolant system and yet another intake bolt pattenr and maybe both have the distributor behind the harmonic balancer.
     
  8. R72K5

    R72K5 Banned

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    learn something new every day, IE the rear balance 86 up

    crazy stuff

    thanks :D
     
  9. diesel4me

    diesel4me 1 ton status Premium Member

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    older is better

    The pre-77 GM 350's had thicker castings on the block,in the front timing cover area and fuel pump mounting surface--a lot of race guys like the older blocks better especially if they are 4 bolt mains..though I've never seen one crack there once!
    My 73 307 has a smaller,solid balancer than most of the "open" bigger 350 and 305 ones,I had a 67 283 that had only a steel flange for the pulleys to bolt to with the 3 bolts,looked more like a pipe floor flange than a balancer(no rubber at all in it!)--I bet GM has a hundred different balancers listed--peek at the listings in a junkyards Hollander interchange book,you'll see what I mean!--its strange they have so many,but they all interchange pretty much unless you put the 400 SB or 454 one on the wrong motor--makes a good cocktail shaker if you do that...:blush:
     

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