Nitrous Express Maximizer 4 User Manual
Page 6

3.2 Tuning Configuration
The Tuning/Configuration selection allows you to set the input configurations as well as enable the
stage selections. Note, when using stage 1 and /or stage 2, the wiring is different than if you
are using the AFR Correction Closed Loop selection.
Under the Tuning / Configuration menu, you may enable Stage 1, Stage 2 or AFR Correction Closed
Loop.
3.4 Wideband Set-up
When using a wide band o2 sensor you will need to enter the calibration data from your wide band
manufacturer into the MAX-4 input config screen.
3.5 AFR Correction Closed Loop
When closed loop control is active, the MAX-4 will reduce pulse width of either the nitrous or fuel
solenoids to achieve your target AFR set point. We recommend initially tuning the nitrous system
with closed loop control disabled. Once you have verified that the nitrous system is achieving a
reasonable AFR with closed loop control disabled, you can enable the closed loop control starting
on sensitivity level 1. If the air fuel ratio never reaches the target set point or is slow to meet the
AFR set point you may increase the sensitivity to a higher level. If you go too high on the sensitivity
level the AFR will overcorrect and will end up oscillating rich, lean, rich, lean and so on. The goal is
to run the lowest sensitivity level possible that will still reach the target AFR.
Although the MAX-4 will pull fuel or nitrous to achieve the target AFR, you will feel a reduction in
power when nitrous is pulled to compensate for a lean condition. For this reason, we recommend
jetting your nitrous system a little rich so the controller will pull fuel instead of nitrous to achieve
the target AFR.
Important!!!! When in ARF Correction Closed Loop mode, the nitrous controller will only control
one stage of nitrous. Furthermore, when the AFR Correction Closed Loop stage is selected in the
software, stage 1 and stage 2 may not be selected. Note: If using the AFR Correction Closed Loop
configuration, connect the ground wires of the nitrous solenoid(s) to the 12awg blue wire of the
MAX-4. Connect the ground wire(s) of the fuel solenoids to the 12awg red wire(s) of the MAX-4.
3.3 RPM
Selecting the enable box within the RPM window turns on the RPM window switch function of the
MAXIMIZER-4. NO check mark removes all RPM related configuration options and tells the
controller to ignore RPM. RPM Multiplier selects the correct pulse count for the RPM counter. Use
the following as a guide to determine the correct setting: TACH signals will typically have 1 pulse
per cylinder during 2 revolutions of the crankshaft (1 full cycle) and therefore the correct setting
would be ÷ (½ the number of cylinders)
Example: When using a TACH signal
� 4 cylinder setting would be ÷2
� 6 cylinder setting would be ÷3
� 8 cylinder setting would be ÷4
Note: for LS1 tach signals set the multiplier to ÷2
b) Using a trigger signal from a coil - first determine how often it fires per revolution of the
crankshaft. The correct setting would be:
� x1 for a waste-spark since it fires each revolution of the crankshaft
� x2 for a full-sequential since it fires every other revolution.
This setting must be verified prior to operation. Verifying this setting will require the unit to be
installed on the vehicle with the engine running. Make sure the rpm display on the software
matches your vehicles tach at idle as well as at mid to high engine RPMs.