Lingenfelter NCC-001, Инструкция по установке и эксплуатации

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Appendices 166
9.4 Appendix D: Glossary of Terms
Air to Fuel Ratio (AFR): Air to Fuel Ratio (AFR) refers to the ratio of the mass of air and fuel inside an
engine at any given time. In theory, the most efficient AFR is where there is
only enough air in the engine to completely burn the fuel, also known as the
Stoichiometric ratio. For standard gasoline, Stoichiometric ratio is 14.7. In
most performance applications, however, the Stoichiometric ratio is rarely
targeted during wide open throttle conditions. Maximum power with standard
gasoline is usually achieved with an AFR of 12.8-13.0. Because Nitrous Oxide
(N2O) contains more oxygen then air does, it is able to burn the fuel at a higher
temperature, creating higher pressure in the cylinders and ultimately more
power. While the added pressure in the combustion chambers increases
horsepower, it can also damage the engine if the AFR is not adjusted
accordingly. In general, you should run a richer AFR when the nitrous is
active.
Hysteresis: Hysteresis refers to a margin above or below the set range in which a
component is allowed to stay enabled or disabled in order to prevent the
component from switching on and off rapidly. If a thermostat, for example, was
to maintain a temperature of exactly 72 degrees, it would most likely overshoot
72 degrees and then undershoot trying to correct itself. Theoretically, this
would cause the thermostat to switch on and off for an infinite period of time,
exhibiting behavior similar to a sine wave function. As one can imagine, the
continual switching of the thermostat would drastically reduce it's functional life
span. For this reason, thermostats and other devices generally have a built-in
hysteresis function that allow them to stay off or on for longer periods of time.
In the case of the NCC-001 Nitrous Control Center, the nitrous is enabled by
several variables for which a hysteresis can be set. The illustrations below
show the behavior of a 5% hysteresis applied to the maximum and minimum
RPM activation thresholds for nitrous through the NCC-001.
NOTE: These graphs below are for illustration purposes only. The actual RPM
hysteresis value is dependent on the user-defined RPM maximum and
minimum values, as well as the user-defined hysteresis percentage.
As the illustration shows, the nitrous enabled condition remains unchanged
until the user-defined maximum value is reached. The illustration has a user-