These are the primary things to adjust to set up the ignition control system.
Distrib Base deg = Adjust this so that the displayed timing matches the actual timing seen on a timing light at low RPM, such as idle, or adjust the distributor so that the timing light matches the display. It’s important to keep this about 10-25 degrees. At cranking, the spark will happen at this value. The system also cannot advance very many degrees above this value – approximately only 20 degrees advance above this value is available at high RPM.
Tach or 2Wire+Coil = If the RPM signal input is using a 2 wire distributor to control the ignition advance with the FiTech ECU, set this to “VRCoil”. The system MUST BE TURNED OFF AFTER MAKING THIS CHANGE – special settings are set up at the software initialization, and it will not work without
this complete power off to power on cycle. If just using the coil negative from a single fire distributor (non-CDI) or tachometer signal from a distributor or CDI box, set this to “Tach.”
VR Advance 4000 = A VR signal, the filtering hardware, and cam chain stretch can lead to some amount of retarding at high RPM. This error can be corrected here, so that the timing light at low RPM matches the displayed value for spark advance, and the spark advance at high RPM, specifically at
4000 RPM matches the timing light.