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Accelerator pump cam position #1 - #2:
white 17cc - 19.5cc
blue 18cc - 20cc
red 18.5cc - 20cc
black 19cc - 18cc
orange 19cc - 24.5cc
green 24cc - 30cc
pink 30cc - 37.5cc
brown 36cc
Pump cams in order of maximum fuel delivery:
black
pink
white
red
green
orange
blue
brown
Pump cams in order of least to maximum shot size (better acceleration and performance):
pink
black
red
white
green
orange
brown
blue
The rating of the 8 available pump cams (Holley kit #20-12) on the basis of the rate/amount of the fuel delivery for the first 30-40 degrees of throttle rotation (the area it matters the most) is generally most useful. Changing from #1 to #2 position will increase the shot size by a proportion of both charts. The cams in order of least to maximum shot size is better for performance and optimum acceleration.
Graphical representation of accelerator pump cams:
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white 17cc - 19.5cc
blue 18cc - 20cc
red 18.5cc - 20cc
black 19cc - 18cc
orange 19cc - 24.5cc
green 24cc - 30cc
pink 30cc - 37.5cc
brown 36cc
Pump cams in order of maximum fuel delivery:
black
pink
white
red
green
orange
blue
brown
Pump cams in order of least to maximum shot size (better acceleration and performance):
pink
black
red
white
green
orange
brown
blue
The rating of the 8 available pump cams (Holley kit #20-12) on the basis of the rate/amount of the fuel delivery for the first 30-40 degrees of throttle rotation (the area it matters the most) is generally most useful. Changing from #1 to #2 position will increase the shot size by a proportion of both charts. The cams in order of least to maximum shot size is better for performance and optimum acceleration.
Graphical representation of accelerator pump cams:
