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stuckatcuse2 · 11-23-2005, 12:27 PM

One reason they may use the cobra MAF is resolution. The ECU uses A/D converters that have a certain number of "steps" per volt. SO... if the Z32 maf maxes out at say 3.2 volts (rather than 5, because they don't use the extra 200HP worth of air flow) the ecu uses only about 64% of its full scale input voltage. Now take the cobra maf, which needs to have values subtracted to stay within HP limits. The ECU now uses 100% of it's input range and either the low or high end is compromised a bit. So with the z32, unless you are making 545 HP, then you are effectively constraining the steps in airflow possible over you're entire power range and are compromising over the entire power range. The cobra however does this only at one end of the spectrum (probably the low end). In otherwords, you'll be able to more precisely tune fuel and timing for a given airflow with a cobra maf than with a z32, up to a certain power level.

11-23-2005, 12:27 PM	#80
stuckatcuse2 Join Date: Oct 2005 Location: Syracuse, NY Posts: 4 Trader Rating: (0)	cobra MAF One reason they may use the cobra MAF is resolution. The ECU uses A/D converters that have a certain number of "steps" per volt. SO... if the Z32 maf maxes out at say 3.2 volts (rather than 5, because they don't use the extra 200HP worth of air flow) the ecu uses only about 64% of its full scale input voltage. Now take the cobra maf, which needs to have values subtracted to stay within HP limits. The ECU now uses 100% of it's input range and either the low or high end is compromised a bit. So with the z32, unless you are making 545 HP, then you are effectively constraining the steps in airflow possible over you're entire power range and are compromising over the entire power range. The cobra however does this only at one end of the spectrum (probably the low end). In otherwords, you'll be able to more precisely tune fuel and timing for a given airflow with a cobra maf than with a z32, up to a certain power level.