AEM 30-6905 Universal Programmable EMS-4 - Manual (Page 114)

Page 114 of 279 EMS-4 Install and Tuning Guide_Rev 1.6
Set up RPM and Load axes
The RPM (X) and Load (Y) axes of the 3D maps must be set up before any calibration work is to
be done. The matrix for all 3D maps except the idle fuel and idle ignition maps is 23 (X) by 17
(Y). The set points may be linear or non linear. Most road cars with relatively mild tuning
characteristics use linear X & Y axes. On engines that are modified with narrow power bands
the non-linear set up is often used. The reason a non-linear set up is good for highly tuned
engines is because the airflow through them is very non linear. The set up of the X & Y axes
allows the tuner to accommodate the non-linear characteristics of the engine by placing the set
points for RPM and Load closer together in the region where drivability is critical.
Linear Load and RPM Setup