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  1. #1
    race24x's Avatar
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    Head CC question and octane boost

    OK so I bought a R&D head with 47cc chambers. I ran the stock head gasket in there to try and push it back to 49cc or close. What do you guys think of running the 47cc chambers without the gasket and running 91 octane fuel. If I am on a place that has only 89 octane mid grade, can I use octane boost to bring it up. I dont want to melt my engine down or have deto. I want fast, but not to sacrafice reliable I ride slow fast all over the place not racing only.


  2. #2
    David 1 FAST VE's Avatar
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    If you can afford to buy and carry 1 gallon of octane boost you would be cool.
    The over the counter stuff does just as advertised; it raises your octane 3-5 points problem is that forgot to add a decimal.
    So you run 89 and put in a bottle and you have 89.5 octane.

    Search up on octane as I have posted a good right up on it that explains a lot.

  3. #3
    race24x's Avatar
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    Thanks man I will check it out. Good info already though like most I am sure when you read 3 - 5 points you assume 89 would be 92-95 octane not the way with the decimal points.

    What would you recommned for a 47 CC head to run safe for octane etc.

  4. #4

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    I would reccommend you measure the squish and compression correctly, to determine the octane needed to run.

    TLR

  5. #5
    race24x's Avatar
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    Does anyone have a step by step to measure squish?

  6. #6
    Bend a couple pieces of solder @ 90 degree and insert them in the cyl. plug hole parallel to the wrist pin. One to the left, one to the right. Make certain you are touching the cyl. wall. Bump engine over a few times with plug wires grounded & measure the smallest squish area on the solder. By doing two pieces @ the same time you wont get inaccurate readings from piston rock on the pin. Hope this helps--Proflow

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