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signal user defined. The default Y-axis is Am Kvol Map which is the one Nira
recommends using. Am Kvol Map is the output from the Throttle to Map
table combined with the MAP sensor reading. The weight of these two inputs
is determined by the data in the Load Select Factor table as described
below.
Throttle-MAP-mix
In engine setups where an accurate MAP-reading is not possible at low loads,
the Throttle To MAP function is helpful.
Two common cases where MAP reading is not an appropriate load signal:
MAP sensor used for high boost pressure readings do not read low
pressure which is one reason of using Throttle MAP mix for accurate
low load mapping
N/A engines with high performance cam shafts do not produce low
pressure in the intake manifold.This is another reason of using throttle
to MAP mix for accurate low load mapping
The table Load Select Factor determines how much the load signal is
determined by the TPS and how much it is determined by the MAP. These
settings are made in “Advanced” mode. The values entered into Throttle to
MAP Table are used by the system as an approximation of the manifold air
pressure as a function of RPM and TPS. If the engine is run without a MAP
sensor, the engine load is entirely determined by the Throttle to Map Table.
Control the mix factor in the table.
Mapping -> Fuel ->Basic -> Load Select Factor Table
0% means that only MAP sensor reading is used.
100% means that only throttle position is used to estimate the pressure. The
estimated pressure is entered in the table below.
Mapping -> Fuel ->Basic -> Throttle to Map Table
For value in-between 0% and 100% a weighted MAP values is calculated
from the MAP sensor and from the Throttle to Map Table. The weighted
MAP value is used in the Volumetric Efficiency Table.
Calculation of MAP value used in the Volumetric Efficiency Table
The MAP value used in the Volumetric Efficiency Table will be.
AM Kvol MAP = Load Select Factor * Throttle to Map Table +
(100% - Load Select Factor ) * MAP sensor reading
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