LETRIPP II XMS4A DIY MANUAL V2.1
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RFECT POWER XMS4A – Engine Management System DIY MANUAL V2.1
22.1
AMP
The AMP sensor is calibrated so the full range of the
sensor gets used. By that I mean a normally
aspirated engine will go to a maximum pressure of 1
bar. So your upper scale shouldn’t be more than 1
bar. With the amp connected and the ignition key on,
this sensor will generate a voltage, normally between
1 and 2 volts. This voltage represents the
atmospheric pressure. Now calibrate the lower and
upper scale so that the XMS4A shows the amp value
at 0.9 with just the ignition on. See the LetRipp
software guide for the actual steps on setting this up
in the software
22.2
ENGINE TEMP
This sensor must be calibrated so the XMS4A can
compensate for cold and hot conditions. You can place
the engine temp sensor in boiling water to get a hot
point reference. Put this voltage into the upper
calibration point. When the sensor cools down it will
have a lower voltage. You need to put in an educated
guess as to the lowest temperature the engine will
experience and what voltage this will be into the lower
calibration point.