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Old 07-25-2018, 11:29 AM
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Tom Vaught Tom Vaught is offline
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Join Date: Dec 2001
Location: The United States of America
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A simple calculation I use all the time when playing with Holleys and Boosted Engine Systems.

The ASSUMED CONSTANTS:

M (dot over the M) = 1
R specific = 1545.348
T1 = 116 degrees F (assumed Underhood Temp)
Ta = 575.67
Z = 1
Pa = 14.6959494
P1 = 0
MW air = 28.9644
Q = 14.51358717 Cubic Feet of Air per Pound of Air

1 divided by 14.51358717 = 0.068900954 Lbs of Air Mass per Cubic Foot of Air.

If you lower the Temperature T1 to 80 degrees F (vs the previous 116 degrees F)
80 degrees F now being AMBIENT Air Temp vs Underhood Air Temp you get:

Q= 13.60596798 Cubic Feet of Air per Pound of Air

1 divided by 13.60596798 = 0.07349716 Lbs of Air Mass per Cubic Foot of Air.

So Temperature of the air entering the carb does make a difference in the Holley Fuel Calibration.

Tom V.

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