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Those familiar with engine dynos will feel right at home with VE (volumetric efficiency) nomenclature. Each cell in the VE table represents--at that engine speed and load--the ratio of actual air/fuel charge in relation to the theoretical maximum allowed by its full, swept volume. The vertical axis is manifold pressure in kilopascals; the horizontal axis is engine rpm. You'll note that unlike the engine dyno, there are many values considerably below 100 percent (1.00). These lower values represent part-throttle conditions. These VE values are used by the processor to calculate the injector pulse time in conjunction with other values such as coolant temperature, ambient air temperature, idle air control disposition and Tau, the manifold puddling constant. As you can probably tell, this fueling strategy is significantly more sophisticated than previous generations of aftermarket engine management. In fact, it's closer to a modern OEM computer in terms of precision, flexibility and processing speed, but with one difference--you can actually tune it without GM's Powertrain department at your disposal.
ACCEL Gen 7 System - Magnum Returns

 Those familiar with engine dynos will feel right at home with VE (volumetric efficiency) nomenclature. Each cell in the VE table represents--at that engine speed and load--the ratio of actual air/fuel charge in relation to the theoretical maximum allowed by its full, swept volume. The vertical axis is manifold pressure in kilopascals; the horizontal axis is engine rpm. You'll note that unlike the engine dyno, there are many values considerably below 100 percent (1.00). These lower values represent part-throttle conditions. These VE values are used by the processor to calculate the injector pulse time in conjunction with other values such as coolant temperature, ambient air temperature, idle air control disposition and Tau, the manifold puddling constant. As you can probably tell, this fueling strategy is significantly more sophisticated than previous generations of aftermarket engine management. In fact, it's closer to a modern OEM computer in terms of precision, flexibility and processing speed, but with one difference--you can actually tune it without GM's Powertrain department at your disposal.  View Related Article

 

 

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