diff --git a/firmware/controllers/algo/event_registry.h b/firmware/controllers/algo/event_registry.h
index 380c1c41f1..6b6a1a5726 100644
--- a/firmware/controllers/algo/event_registry.h
+++ b/firmware/controllers/algo/event_registry.h
@@ -37,11 +37,17 @@ class IgnitionEvent {
 public:
 	IgnitionEvent();
 	IgnitionOutputPin *outputs[MAX_OUTPUTS_FOR_IGNITION];
-	scheduling_s signalTimerUp;
+	scheduling_s dwellStartTimer;
 	scheduling_s signalTimerDown;
+	/**
+	 * Desired timing advance
+	 */
 	angle_t advance = NAN;
 	floatms_t sparkDwell;
-	uint32_t startOfDwell;
+	/**
+	 * this timestamp allows us to measure actual dwell time
+	 */
+	uint32_t actualStartOfDwellNt;
 	event_trigger_position_s dwellPosition;
 	event_trigger_position_s sparkPosition;
 	/**
@@ -49,7 +55,7 @@ public:
 	 */
 	IgnitionEvent *next = nullptr;
 	/**
-	 * Sequential number of all spark events
+	 * Sequential number of currently processed spark event
 	 * @see globalSparkIdCounter
 	 */
 	int sparkId = 0;
@@ -68,7 +74,6 @@ public:
 
 class IgnitionEventList {
 public:
-	IgnitionEventList();
 	IgnitionEvent elements[MAX_IGNITION_EVENT_COUNT];
-	bool isReady;
+	bool isReady = false;
 };
diff --git a/firmware/controllers/scheduling/signal_executor.h b/firmware/controllers/scheduling/signal_executor.h
index bbfb7421c4..c8070a0a53 100644
--- a/firmware/controllers/scheduling/signal_executor.h
+++ b/firmware/controllers/scheduling/signal_executor.h
@@ -25,7 +25,7 @@ class InjectionSignalPair {
 public:
 	InjectionSignalPair();
 	scheduling_s signalTimerUp;
-	scheduling_s signalTimerDown;
+	scheduling_s endOfInjectionEvent;
 
 	/**
 	 * we need atomic flag so that we do not schedule a new pair of up/down before previous down was executed.
diff --git a/firmware/controllers/trigger/main_trigger_callback.cpp b/firmware/controllers/trigger/main_trigger_callback.cpp
index fd9860d663..78703084ed 100644
--- a/firmware/controllers/trigger/main_trigger_callback.cpp
+++ b/firmware/controllers/trigger/main_trigger_callback.cpp
@@ -282,7 +282,7 @@ static ALWAYS_INLINE void handleFuelInjectionEvent(int injEventIndex, InjectionE
 
 		scheduling_s * sUp = &pair->signalTimerUp;
 // todo: sequential need this logic as well, just do not forget to clear flag		pair->isScheduled = true;
-		scheduling_s * sDown = &pair->signalTimerDown;
+		scheduling_s * sDown = &pair->endOfInjectionEvent;
 
 		engine->executor.scheduleForLater(sUp, (int) injectionStartDelayUs, (schfunc_t) &startSimultaniousInjection, engine);
 		engine->executor.scheduleForLater(sDown, (int) injectionStartDelayUs + durationUs,
@@ -323,7 +323,7 @@ static ALWAYS_INLINE void handleFuelInjectionEvent(int injEventIndex, InjectionE
 		pair->outputs[0] = output;
 		pair->outputs[1] = event->outputs[1];
 		scheduling_s * sUp = &pair->signalTimerUp;
-		scheduling_s * sDown = &pair->signalTimerDown;
+		scheduling_s * sDown = &pair->endOfInjectionEvent;
 
 		pair->isScheduled = true;
 		pair->event = event;
@@ -582,7 +582,7 @@ void startPrimeInjectionPulse(DECLARE_ENGINE_PARAMETER_SIGNATURE) {
 		primeInjEvent.ownIndex = 0;
 		primeInjEvent.isSimultanious = true;
 
-		scheduling_s *sDown = &ENGINE(fuelActuators[0]).signalTimerDown;
+		scheduling_s *sDown = &ENGINE(fuelActuators[0]).endOfInjectionEvent;
 		// When the engine is hot, basically we don't need prime inj.pulse, so we use an interpolation over temperature (falloff).
 		// If 'primeInjFalloffTemperature' is not specified (by default), we have a prime pulse deactivation at zero celsius degrees, which is okay.
 		const float maxPrimeInjAtTemperature = -40.0f;	// at this temperature the pulse is maximal.
diff --git a/firmware/controllers/trigger/spark_logic.cpp b/firmware/controllers/trigger/spark_logic.cpp
index 667d4b3a7a..139783657b 100644
--- a/firmware/controllers/trigger/spark_logic.cpp
+++ b/firmware/controllers/trigger/spark_logic.cpp
@@ -27,10 +27,6 @@ static Logging *logger;
 
 static const char *prevSparkName = nullptr;
 
-IgnitionEventList::IgnitionEventList() {
-	isReady = false;
-}
-
 int isInjectionEnabled(DECLARE_ENGINE_PARAMETER_SIGNATURE) {
 	// todo: is this worth a method? should this be inlined?
 	return CONFIG(isInjectionEnabled);
@@ -129,7 +125,7 @@ void fireSparkAndPrepareNextSchedule(IgnitionEvent *event) {
 	}
 #if !EFI_UNIT_TEST
 if (engineConfiguration->debugMode == DBG_DWELL_METRIC) {
-	uint32_t actualDwellDurationNt = getTimeNowLowerNt() - event->startOfDwell;
+	uint32_t actualDwellDurationNt = getTimeNowLowerNt() - event->actualStartOfDwellNt;
 	/**
 	 * ratio of desired dwell duration to actual dwell duration gives us some idea of how good is input trigger jitter
 	 */
@@ -201,7 +197,7 @@ static void startDwellByTurningSparkPinHigh(IgnitionEvent *event, IgnitionOutput
 }
 
 void turnSparkPinHigh(IgnitionEvent *event) {
-	event->startOfDwell = getTimeNowLowerNt();
+	event->actualStartOfDwellNt = getTimeNowLowerNt();
 	for (int i = 0; i< MAX_OUTPUTS_FOR_IGNITION;i++) {
 		IgnitionOutputPin *output = event->outputs[i];
 		if (output != NULL) {
@@ -241,7 +237,7 @@ static ALWAYS_INLINE void handleSparkEvent(bool limitedSpark, uint32_t trgEventI
 	 * We are alternating two event lists in order to avoid a potential issue around revolution boundary
 	 * when an event is scheduled within the next revolution.
 	 */
-	scheduling_s * sUp = &iEvent->signalTimerUp;
+	scheduling_s * sUp = &iEvent->dwellStartTimer;
 	scheduling_s * sDown = &iEvent->signalTimerDown;
 
 
@@ -348,7 +344,7 @@ static ALWAYS_INLINE void prepareIgnitionSchedule(DECLARE_ENGINE_PARAMETER_SIGNA
 	engine->m.beforeIgnitionSch = getTimeNowLowerNt();
 	/**
 	 * TODO: warning. there is a bit of a hack here, todo: improve.
-	 * currently output signals/times signalTimerUp from the previous revolutions could be
+	 * currently output signals/times dwellStartTimer from the previous revolutions could be
 	 * still used because they have crossed the revolution boundary
 	 * but we are already re-purposing the output signals, but everything works because we
 	 * are not affecting that space in memory. todo: use two instances of 'ignitionSignals'