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Rotary engine specific settings

The current Rotary menu is a trailing-spark feature, not an engine preset. It enables a secondary ignition event after each configured primary event. Leading ignition still uses the normal ignition outputs, firing order, advance table, dwell table, and trigger configuration.

Configure leading and trailing sparks​

  1. Configure the primary trigger, engine cycle, firing order, and leading ignition outputs. Verify the leading timing and phase first.
  2. In Rotary, enable Enable Trailing Sparks and assign the trailing outputs. The current TunerStudio dialog exposes trailing pins 1 through 4.
  3. Calibrate the 8 x 8 Trailing spark advance table. Its RPM and load axes are independent, and trailingSparkLoadSource selects the load coordinate used by engineState.trailingSparkAngle.

trailingIgnitionTable is the angular delay after the main event, not a separate total BTDC advance. For each main ignition event, the firmware loads that offset and schedules charging and firing on the matching trailing output. The trailing dwell is the main event's dwell snapshot. The primary minimumIgnitionTiming and maximumIgnitionTiming clamp does not clamp the trailing angle.

Firing-order and paired-output cautions​

The rotary menu does not derive rotor count, leading/trailing pairing, trigger phase, or output assignment. A two-rotor tune represented by two primary events therefore needs both leading events and their corresponding trailing outputs configured explicitly; this page makes no universal claim about other rotary arrangements.

pairedOddFireWastedSpark is a generic shared-coil option. In Wasted Spark mode it drives one output for a companion pair from both cylinder events and suppresses the separate +360-degree odd-fire re-fire path. It is not a rotary leading/trailing switch and does not create trailing outputs.

Checks and limits​

Verify rising/falling edge and polarity on each leading and trailing output, then confirm that only the intended coil fires. If trailing spark is absent, check enableTrailingSparks, the trailing output, the selected table coordinate, and a valid, finite load. Confirm the table axes are ascending. Experimental ignition cycle-profile and time-budget planners change primary ignition timing conversion; they do not replace the trailing-angle path. Coil dwell, coil capacity, and safe trailing timing require hardware validation.

Sources​