Rod length/ Rod stroke ratio

Discussion in 'PSI Superchargers Tech Questions' started by Blown Altered, Jul 16, 2012.

  1. Blown Altered

    Blown Altered New Member

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    I am building a short stroke small inch hemi in a short deck block. Does rod stroke ratio matter as much in a blown alcohol motor as it does in a naturally aspirated motor. I have a 3.250 stroke with a 6.900 rod for a 2.12 ratio.
     
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  2. SoDak

    SoDak Active Member

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    I pay no attention to rod ratio, IMO it has so little to do with HP its not worth an ounce of emphasis.
     
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  3. 23T Hemmee

    23T Hemmee Member

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    It's more of an issue with a normally aspirated combo, cam timing being a lot more critical in regard to intake charge. The blower takes care of that. R/S ratio isn't nearly as important until it's short enough to push the piston out the side of the cylinder.
     
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  4. Ron C

    Ron C Jr. Dragster

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    Important to Naturally aspirated.....??? Let's look at the premier "naturally aspirated" class........Pro Stock. How do they address the importance of rod length. They first determine the deck height, which will be as short as possible, then they design the ring package location which will include where the pin is to be located. Then they measure the center of the pin to the center of the crank rod journal. That then gives them the rod length,....what ever it is.

    It seems to be pretty low on the importance list compared to the others things above it.

    Blessings...........Ron
     
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