Crank Index Offset Setup

Crank Index Offset Setup

The Crank Index Offset Setup is a critical configuration step.  It is the point in which the ECU has latched onto the “timing” of the engine as a reference of TDC #1 Compression.  Depending on the trigger decoding mode selected, the ECU will latch onto a an “Index Tooth”, and this Index point generally does not reference TDC (Top Dead Center) cylinder #1 compression.  The Crank Index Offset Position is what allows the ECU to offset the Index Tooth position to allow the ECU to keep time the engine appropriately.   

The Crank Index Offset Value = TDC Compression Number 1 is X.X number of degrees BEFORE “Index Tooth” position

The Crank Index Offset MUST always be checked regardless of trigger pre-configuration. 

1)  Always check crank index position at ignition lock angle 0.0 (especially when running waste spark). 

2)  Ignition delay time should be validated at this time and adjusted.

3)  As RPM is increased, timing should stay at the ignition lock angle.  

     If this does not occur - Adjust the ignition delay time until this is achieved.  

** In Wasted Spark mode, set ignition lock angle to 0.0 due to timing light identifying the wrong RPM reading and mis-calculating advance

** When Ignition Lock Enable is ON, Ignition Lock Angle value overrides all other timing values in ECU

Tuning Tip: 

The fuel injectors can be disabled to validate the initial Crank Index Offset value.prior to starting the engine.

Config -> Fuel -> Fuel Main -> Injection Mode -> Off

Direct fire engines may be 360deg out of cycle which can be corrected numerically.