diff --git a/firmware/config/boards/microrusefi/board.mk b/firmware/config/boards/microrusefi/board.mk
index 6e14f99272..edcf4b3e2b 100644
--- a/firmware/config/boards/microrusefi/board.mk
+++ b/firmware/config/boards/microrusefi/board.mk
@@ -30,5 +30,10 @@ ifeq ($(LED_CRITICAL_ERROR_BRAIN_PIN),)
 endif
 
 
+# breaking TTL thus breaking Bluetooth for microRusEFI in order to enable SPI3 for SD card
+EFI_CONSOLE_TTL_PINS = -DEFI_CONSOLE_TX_BRAIN_PIN=GPIOE_15 -DEFI_CONSOLE_RX_BRAIN_PIN=GPIOE_14
+
+
 # Add them all together
-DDEFS += $(MCU_DEFS) -DEFI_USE_OSC=TRUE -DFIRMWARE_ID=\"microRusEfi\" $(DEFAULT_ENGINE_TYPE) $(LED_CRITICAL_ERROR_BRAIN_PIN)
+DDEFS += $(MCU_DEFS) -DEFI_USE_OSC=TRUE -DFIRMWARE_ID=\"microRusEfi\" $(DEFAULT_ENGINE_TYPE) $(LED_CRITICAL_ERROR_BRAIN_PIN) $(EFI_CONSOLE_TTL_PINS)
+
diff --git a/firmware/config/boards/microrusefi/board_configuration.cpp b/firmware/config/boards/microrusefi/board_configuration.cpp
index e729650867..356d971c46 100644
--- a/firmware/config/boards/microrusefi/board_configuration.cpp
+++ b/firmware/config/boards/microrusefi/board_configuration.cpp
@@ -86,6 +86,7 @@ static void setupVbatt() {
 	// set vbatt_divider 8.23
 	// R139=39k high side/R141=10k low side multiplied by above analogInputDividerCoefficient = 8.232f
 	engineConfiguration->vbattDividerCoeff = (49.0f / 10.0f) * engineConfiguration->analogInputDividerCoefficient;
+	// PC1, pin #1 input +12 from Main Relay. Main Relay controlled by TLE8888
 	engineConfiguration->vbattAdcChannel = EFI_ADC_11;
 
 	engineConfiguration->adcVcc = 3.29f;
@@ -198,6 +199,14 @@ void setBoardConfigurationOverrides(void) {
 	// GPIOE_8: "35 - GP Out 1"
 	engineConfiguration->fuelPumpPin = GPIOE_8;
 
+	engineConfiguration->sdCardSpiDevice = SPI_DEVICE_3;
+	engineConfiguration->spi3mosiPin = GPIOC_12;
+	engineConfiguration->spi3misoPin = GPIOC_11;
+	engineConfiguration->spi3sckPin = GPIOC_10;
+	engineConfiguration->sdCardCsPin = GPIOB_9;
+	CONFIG(is_enabled_spi_3) = true;
+//	engineConfiguration->isSdCardEnabled = true;
+
 
 	// TLE8888 high current low side: VVT2 IN9 / OUT5
 	// GPIOE_10: "3 - Lowside 2"
diff --git a/firmware/config/boards/microrusefi/prepend.txt b/firmware/config/boards/microrusefi/prepend.txt
index f11e020f1a..73e90b6153 100644
--- a/firmware/config/boards/microrusefi/prepend.txt
+++ b/firmware/config/boards/microrusefi/prepend.txt
@@ -7,7 +7,7 @@
 #define ts_show_gps false
 #define ts_show_etb_pins false
 #define ts_show_analog_divider false
-#define ts_show_spi false
-#define ts_show_sd_card false
+#define ts_show_spi true
+#define ts_show_sd_card true
 #define ts_show_can_pins false
 #define ts_show_tunerstudio_port false
diff --git a/firmware/controllers/algo/rusefi_enums.h b/firmware/controllers/algo/rusefi_enums.h
index 69b48ea11c..d1e5ecd7b3 100644
--- a/firmware/controllers/algo/rusefi_enums.h
+++ b/firmware/controllers/algo/rusefi_enums.h
@@ -609,6 +609,11 @@ typedef enum __attribute__ ((__packed__)) {
 	_150KHz
 } spi_speed_e;
 
+
+/**
+ * See spi3mosiPin
+ * See spi2MisoMode
+ */
 typedef enum __attribute__ ((__packed__)) {
 	SPI_NONE = 0,
 	SPI_DEVICE_1 = 1,
diff --git a/firmware/controllers/algo/rusefi_hw_enums.h b/firmware/controllers/algo/rusefi_hw_enums.h
index 2369fe0d28..c175c2f372 100644
--- a/firmware/controllers/algo/rusefi_hw_enums.h
+++ b/firmware/controllers/algo/rusefi_hw_enums.h
@@ -161,7 +161,6 @@ typedef enum __attribute__ ((__packed__)) {
 	GPIOH_15 = 129,
 
 	/* TLE6240 pins go right after on chips */
-	//#define TLE6240_PIN(n)		((brain_pin_e)((int)BRAIN_PIN_LAST_ONCHIP + 1 + (n)))
 	TLE6240_PIN_1 = 130,
 	TLE6240_PIN_2 = 131,
 	TLE6240_PIN_3 = 132,
@@ -180,7 +179,6 @@ typedef enum __attribute__ ((__packed__)) {
 	TLE6240_PIN_16 = 145,
 
 	/* MC33972 pins go right after TLE6240 */
-	//#define MC33972_PIN(n)		((brain_pin_e)((int)BRAIN_PIN_LAST_ONCHIP + 1 + 16 + (n)))
 	MC33972_PIN_1 = 146,
 	MC33972_PIN_21 = 166,
 	MC33972_PIN_22 = 167,
diff --git a/firmware/controllers/engine_controller.cpp b/firmware/controllers/engine_controller.cpp
index 771be483ef..2fb41cfa90 100644
--- a/firmware/controllers/engine_controller.cpp
+++ b/firmware/controllers/engine_controller.cpp
@@ -696,7 +696,7 @@ void initEngineContoller(Logging *sharedLogger DECLARE_ENGINE_PARAMETER_SUFFIX)
  * UNUSED_SIZE contants.
  */
 #ifndef RAM_UNUSED_SIZE
-#define RAM_UNUSED_SIZE 12200
+#define RAM_UNUSED_SIZE 10900
 #endif
 #ifndef CCM_UNUSED_SIZE
 #define CCM_UNUSED_SIZE 2900
@@ -717,6 +717,6 @@ int getRusEfiVersion(void) {
 	if (initBootloader() != 0)
 		return 123;
 #endif /* EFI_BOOTLOADER_INCLUDE_CODE */
-	return 20200512;
+	return 20200513;
 }
 #endif /* EFI_UNIT_TEST */
diff --git a/firmware/controllers/engine_cycle/main_trigger_callback.cpp b/firmware/controllers/engine_cycle/main_trigger_callback.cpp
index ecb999e941..fca28931cf 100644
--- a/firmware/controllers/engine_cycle/main_trigger_callback.cpp
+++ b/firmware/controllers/engine_cycle/main_trigger_callback.cpp
@@ -168,7 +168,7 @@ void turnInjectionPinLow(InjectionEvent *event) {
 	ENGINE(injectionEvents.addFuelEventsForCylinder(event->ownIndex PASS_ENGINE_PARAMETER_SUFFIX));
 }
 
-static ALWAYS_INLINE void handleFuelInjectionEvent(int injEventIndex, InjectionEvent *event,
+void handleFuelInjectionEvent(int injEventIndex, InjectionEvent *event,
 		int rpm, efitick_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX) {
 
 	/**
@@ -310,6 +310,11 @@ static ALWAYS_INLINE void handleFuel(const bool limitedFuel, uint32_t trgEventIn
 		return;
 	}
 
+	// If duty cycle is high, impose a fuel cut rev limiter.
+	// This is safer than attempting to limp along with injectors or a pump that are out of flow.
+	if (getInjectorDutyCycle(rpm PASS_ENGINE_PARAMETER_SUFFIX) > 96.0f) {
+		return;
+	}
 
 	/**
 	 * Ignition events are defined by addFuelEvents() according to selected
diff --git a/firmware/controllers/engine_cycle/main_trigger_callback.h b/firmware/controllers/engine_cycle/main_trigger_callback.h
index d4f1c33d4d..a61e0ca5f4 100644
--- a/firmware/controllers/engine_cycle/main_trigger_callback.h
+++ b/firmware/controllers/engine_cycle/main_trigger_callback.h
@@ -24,3 +24,7 @@ void turnInjectionPinLow(InjectionEvent *event);
 
 // reset injection switch counter if the engine started spinning
 void updatePrimeInjectionPulseState(DECLARE_ENGINE_PARAMETER_SIGNATURE);
+
+// Internal use only - exposed for tests
+void handleFuelInjectionEvent(int injEventIndex, InjectionEvent *event,
+		int rpm, efitick_t nowNt DECLARE_ENGINE_PARAMETER_SUFFIX);
diff --git a/firmware/hw_layer/smart_gpio.h b/firmware/hw_layer/smart_gpio.h
index 024c6738a9..bb481a90c9 100644
--- a/firmware/hw_layer/smart_gpio.h
+++ b/firmware/hw_layer/smart_gpio.h
@@ -24,11 +24,6 @@
  #define BOARD_EXT_GPIOCHIPS			(BOARD_TLE6240_COUNT + BOARD_MC33972_COUNT + BOARD_TLE8888_COUNT)
 #endif
 
-/* TLE6240 pins go right after on chips */
-#define TLE6240_PIN(n)		((brain_pin_e)((int)BRAIN_PIN_LAST_ONCHIP + 1 + (n)))
-/* MC33972 pins go right after TLE6240 */
-#define MC33972_PIN(n)		((brain_pin_e)((int)BRAIN_PIN_LAST_ONCHIP + 1 + 16 + (n)))
-
 void initSmartGpio(void);
 void startSmartCsPins(void);
 void stopSmartCsPins(void);
diff --git a/unit_tests/global_execution_queue.cpp b/unit_tests/global_execution_queue.cpp
index 24cdd0df54..4b20117b3d 100644
--- a/unit_tests/global_execution_queue.cpp
+++ b/unit_tests/global_execution_queue.cpp
@@ -14,6 +14,12 @@ void TestExecutor::scheduleForLater(scheduling_s *scheduling, int delayUs, actio
 	if (debugSignalExecutor) {
 		printf("scheduleTask %d\r\n", delayUs);
 	}
+
+	if (m_mockExecutor) {
+		m_mockExecutor->scheduleForLater(scheduling, delayUs, action);
+		return;
+	}
+
 	scheduleByTimestamp(scheduling, getTimeNowUs() + delayUs, action);
 }
 
@@ -37,9 +43,24 @@ void TestExecutor::scheduleByTimestamp(scheduling_s *scheduling, efitimeus_t tim
 	if (debugSignalExecutor) {
 		printf("scheduleByTime %d\r\n", timeUs);
 	}
+
+	if (m_mockExecutor) {
+		m_mockExecutor->scheduleByTimestamp(scheduling, timeUs, action);
+		return;
+	}
+
 	schedulingQueue.insertTask(scheduling, timeUs, action);
 }
 
 void TestExecutor::scheduleByTimestampNt(scheduling_s* scheduling, efitick_t timeNt, action_s action) {
+	if (m_mockExecutor) {
+		m_mockExecutor->scheduleByTimestampNt(scheduling, timeNt, action);
+		return;
+	}
+
 	scheduleByTimestamp(scheduling, NT2US(timeNt), action);
 }
+
+void TestExecutor::setMockExecutor(ExecutorInterface* exec) {
+	m_mockExecutor = exec;
+}
diff --git a/unit_tests/global_execution_queue.h b/unit_tests/global_execution_queue.h
index f568ad9954..c5ecec4435 100644
--- a/unit_tests/global_execution_queue.h
+++ b/unit_tests/global_execution_queue.h
@@ -19,6 +19,9 @@ public:
 	int executeAll(efitime_t now);
 	int size();
 	scheduling_s* getForUnitTest(int index);
+
+	void setMockExecutor(ExecutorInterface* exec);
 private:
 	EventQueue schedulingQueue;
+	ExecutorInterface* m_mockExecutor = nullptr;
 };
diff --git a/unit_tests/mocks.h b/unit_tests/mocks.h
index a3dca2df88..0aa45f47bf 100644
--- a/unit_tests/mocks.h
+++ b/unit_tests/mocks.h
@@ -40,3 +40,10 @@ class MockPwm : public SimplePwm {
 public:
 	MOCK_METHOD(void, setSimplePwmDutyCycle, (float dutyCycle), (override));
 };
+
+class MockExecutor : public TestExecutor {
+public:
+	MOCK_METHOD(void, scheduleByTimestamp, (scheduling_s *scheduling, efitimeus_t timeUs, action_s action), (override));
+	MOCK_METHOD(void, scheduleByTimestampNt, (scheduling_s *scheduling, efitime_t timeUs, action_s action), (override));
+	MOCK_METHOD(void, scheduleForLater, (scheduling_s *scheduling, int delayUs, action_s action), (override));
+};
diff --git a/unit_tests/tests/tests.mk b/unit_tests/tests/tests.mk
index b54a80cad1..e4f0be8697 100644
--- a/unit_tests/tests/tests.mk
+++ b/unit_tests/tests/tests.mk
@@ -5,6 +5,7 @@ TESTS_SRC_CPP = \
 	tests/trigger/test_trigger_multi_sync.cpp \
 	tests/trigger/test_cam_vvt_input.cpp \
 	tests/trigger/test_2jz_vvt.cpp \
+	tests/trigger/test_injection_scheduling.cpp \
 	tests/test_util.cpp \
 	tests/test_ion.cpp \
 	tests/test_aux_valves.cpp \
diff --git a/unit_tests/tests/trigger/test_injection_scheduling.cpp b/unit_tests/tests/trigger/test_injection_scheduling.cpp
new file mode 100644
index 0000000000..071338461b
--- /dev/null
+++ b/unit_tests/tests/trigger/test_injection_scheduling.cpp
@@ -0,0 +1,40 @@
+#include "engine_test_helper.h"
+#include "main_trigger_callback.h"
+
+#include <gmock/gmock.h>
+#include "mocks.h"
+
+using ::testing::_;
+using ::testing::StrictMock;
+using ::testing::InSequence;
+
+TEST(injectionScheduling, NormalDutyCycle) {
+	StrictMock<MockExecutor> mockExec;
+
+	WITH_ENGINE_TEST_HELPER(TEST_ENGINE);
+	engine->executor.setMockExecutor(&mockExec);
+
+	efitick_t nowNt = 1000000;
+
+	InjectionEvent event;
+	InjectorOutputPin pin;
+	pin.injectorIndex = 0;
+	event.outputs[0] = &pin;
+
+	// Injection duration of 20ms
+	engine->injectionDuration = 20.0f;
+
+	{
+		InSequence is;
+
+		// Should schedule one normal injection:
+		// rising edge now
+		EXPECT_CALL(mockExec, scheduleByTimestampNt(&event.signalTimerUp, nowNt + 0, _));
+		// falling edge 10ms later
+		EXPECT_CALL(mockExec, scheduleByTimestampNt(&event.endOfInjectionEvent, nowNt + MS2NT(20), _));
+	}
+
+	engine->rpmCalculator.oneDegreeUs = 100;
+
+	handleFuelInjectionEvent(0, &event, 1000, nowNt PASS_ENGINE_PARAMETER_SUFFIX);
+}