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Thread: Ramp rate tables

  1. #1
    Tuner in Training
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    Ramp rate tables

    Is anyone familiar with the variable cam ramp rate tables?
    I'm familiar with cam lobe ramp rate so, my question is, are these tables the same?
    Is the ramp positive table the ramp rate for the valve opening side of the lobe and the ramp negative table for the valve closing side of the lobe?
    Are the values the crank degrees from lobe base to lobe centerline?
    Example, a value of .20 means it takes .20 crank degrees to fully open the valve for a faster opening rate and, .40 crank degrees for a slower ramp rate?

    Thanks.

  2. #2
    Senior Tuner Higgs Boson's Avatar
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    I don't think this is ramp rate for the cam lobe as that is ground in. My understanding is this is the ramp rate for the VVT, like how fast does it change degrees.

  3. #3
    Tuner in Training
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    Ok, That makes sense.
    I know ramp rate is ground into the cam but, I was thinking that these tables advance or retard the cam to, in affect, create lobe ramp rates.
    But, your explanation makes more sense.
    Thank you.

  4. #4
    Senior Tuner
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    You couldn't do that because 1 cam is running all the valves. So some are opening and some are closing all at the same time.

  5. #5
    so the higher the number, the quicker it ramps correct