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Rocker arm ratios, what do they mean?

Discussion in 'The Garage' started by jakeslim, Jul 24, 2004.

  1. jakeslim

    jakeslim 1/2 ton status

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    What's the difference between 1.5 ratio rocker arms and 1.6? The heads are late 80's centerbolt if that matters.
    /forums/images/graemlins/1zhelp.gif
     
  2. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    It is the ratio that the rocker arm opens the valve relative to the cam.

    Lets just say you have a cam that is .325" lift at the cam lobe and you are using 1.5 ratio rocker arms, that means the rocker arm makes the cam lobe lift 1.5 times greater at the valve for a valve lift of .487", the same cam with 1.6 ratio rocker arms would have a valve lift of .520"
     
  3. hi pinion

    hi pinion 3/4 ton status

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    DU!!!!!! /forums/images/graemlins/rotfl.gif /forums/images/graemlins/histerical.gif
     
  4. jakeslim

    jakeslim 1/2 ton status

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    Thanks /forums/images/graemlins/waytogo.gif Can I use either and is one better option? Its a 350 with stock cam, etc. (87 and up block and heads)
     
  5. hi pinion

    hi pinion 3/4 ton status

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    You have much to learn baby bird /forums/images/graemlins/histerical.gif /forums/images/graemlins/rotfl.gif
     
  6. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Nothing wrong with 1.5 ratio, this is an easy way to achieve more lift without changing a cam or changing duration. Some racers use 1.6 on the exhaust and 1.5 on the intake and other racers use 1.6 on only a couple different valves that need more time to get fuel into the cylinder because of a longer runner. /forums/images/graemlins/thumb.gif
     
  7. 75-K5

    75-K5 3/4 ton status

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    [ QUOTE ]
    You have much to learn baby bird /forums/images/graemlins/histerical.gif /forums/images/graemlins/rotfl.gif

    [/ QUOTE ]

    I got that one /forums/images/graemlins/yikes.gif /forums/images/graemlins/histerical.gif /forums/images/graemlins/histerical.gif

    I have a nice gear driven 203 if anyone wants it /forums/images/graemlins/rolleyes.gif
     
  8. jakeslim

    jakeslim 1/2 ton status

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    [ QUOTE ]
    You have much to learn baby bird /forums/images/graemlins/histerical.gif /forums/images/graemlins/rotfl.gif

    [/ QUOTE ]

    "don't pee on MY lawn" /forums/images/graemlins/histerical.gif /forums/images/graemlins/peace.gif


    Thanks, I'll go with the 1.5's
     
  9. hi pinion

    hi pinion 3/4 ton status

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    [ QUOTE ]
    [ QUOTE ]
    You have much to learn baby bird /forums/images/graemlins/histerical.gif /forums/images/graemlins/rotfl.gif

    [/ QUOTE ]

    "don't pee on MY lawn" /forums/images/graemlins/histerical.gif /forums/images/graemlins/peace.gif


    Thanks, I'll go with the 1.5's

    [/ QUOTE ] /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif FELLING VERY GOOD TONIGHT!!! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/peace.gif /forums/images/graemlins/thumb.gif
     

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