NismotronicSA has 2 sets of 2 maps each, total of 4 20x20 maps for both fuel and timing. The load source (MAF,MAP,alpha-N) is selected for each set and switching between Primary and Secondary maps within that set is fully programmable.
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NismotronicSA Help Documents
NismotronicSA TunerCodeSA Help
Map Switching Programming
Map Switch Programming Triggers