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Stock 350 TBI Compression Ratio and Head CC ?

Discussion in 'The Garage' started by 83ZZ502_Jimmy, Dec 31, 2003.

  1. 83ZZ502_Jimmy

    83ZZ502_Jimmy 1/2 ton status

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    I have a stock 350 tbi and I am looking for the stock head CC size and compression ratio.

    Also does anyone know if it would be 2 or 4 bolt mains?

    Thanks in advance, /forums/images/graemlins/thumb.gif
    John
     
  2. 88Silverado

    88Silverado 1/2 ton status

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    Most stock 350's run 76cc heads and the compression ratio should be around 8.2
     
  3. Thunder

    Thunder 3/4 ton status

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    8.2 to 1 and 76cc
    For the most part with TBI:
    Light duty trucks got 2 bolt mains(under 7200 GVW)
    Heavy duty got 4 bolts.
     
  4. Hardcore

    Hardcore 1/2 ton status

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    Is there any other difference between the LD and HD engines. I see the Goodwrench replacement for the 4 bolt is $100 more than the 2 bolt. Is everything else the same? /forums/images/graemlins/ears.gif
     
  5. 83ZZ502_Jimmy

    83ZZ502_Jimmy 1/2 ton status

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    Thanks guys! /forums/images/graemlins/thumb.gif

    John
     
  6. Thunder

    Thunder 3/4 ton status

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    I am not sure about the replacement engines. But from my experience with them I have found the main difference in the stock TBI engines is in the heads. The heads in the HD engines flow even worse than the ones in the 1/2 tons. Many (not all) 89 and up 1/2 tons and K5s and up got swirl port heads which aren't half bad /forums/images/graemlins/thumb.gif)
    Because of the head design.The HD engines build more torque sooner in the RPM range,but run out of air on top end.

    GM used 3 or 4 diferent heads with small variations in design for diferent applications on TBI 350s.
     

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