Edelbrock 3670 User Manual - page 118
118
4.3.2
Volumetric Efficiency Map
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Volumetric Efficiency Map
The Volumetric Efficiency map is a representation of your engine's airflow characteristics.
It needs to be properly calibrated for the control strategies to accurately determine
fueling under all speed and load conditions, and to provide accurate altitude
compensation. Your system has a base VE map that should get you up and running
quickly. Volumetric efficiency is the amount of air that a cylinder retains vs the amount
that it can theoretically hold (displacement). At speed, a cylinder is generally not able to
fill to 100% or a VE of 1.00; due to intake & exhaust restriction, throttle blade
restriction, and pumping efficiency influenced mainly by RPM and camshaft
characteristics. Naturally aspirated engines that have extremely strong tuning may
exceed 100% volumetric efficiency, but generally only supercharged engines exceed one
atmosphere by a significant amount. If you are running a boosted engine, you will need
to select the appropriate MAP sensor in the setup wizard. When you do, the application
will automatically rescale the pressure ratio ordinates to reflect the additional pressure
range.