Duration of Camshaft.

Discussion in 'FXR Models' started by Jonk777, Sep 18, 2014.

  1. Jonk777

    Jonk777 Member

    The duration of the camshaft. Duration means the time it takes to open up the valves on the exhaust and intake. For a performance motor would you need a cam that has low duration or high duration. Depending upon the compression size of the pistons and valves size. Along with the cabbie.:newsmile083:
  2. bc45

    bc45 Active Member


    The correct definition of cam duration is: The amount of time, measured in degrees of crankshaft rotation, an intake or exhaust valve is held open.

    Is high or low duration better? depends on what the motor is built to do.
    First you need to figure out what you want the motor, to do and RPM you will be running then talk to a good builder to figure out what cam you should be using to achieve those goals. there is more to choosing a cam then duration.
    Cam Specs & Effects, duration centerline separation and lift, more on pereformance engine parts
    hear is a link on basic cam measurements and the what it effects.
  3. Jeff Klarich

    Jeff Klarich Well-Known Member Contributor

    Spot on bc45, good and accurate information.:good