Spark Gap X4: Standalone Engine Management Kit (Short Back-Order - Please Read Description)

$199.99

⚠ Back-Order Notice (Estimated shipping time: 2–3 weeks as of November 14, 2025)
I’m currently waiting on a shipment of connectors, which has delayed final assembly of the next Spark Gap X4 batch. The connector delivery is estimated for November 21. Once they arrive, I’ll finish building and testing immediately. Orders should ship within 2–5 business days after the connectors are delivered.

Please note: Only new orders placed while this notice is active are affected by the back-order. All previous orders have already shipped.

Thank you for your patience. This one part is holding everything up, but the moment it lands, I’ll get these out the door.

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The Spark Gap X4 is a feature-filled 4-channel standalone ECU powered by the Atmega2560 and fully compatible with official Speeduino firmware. It supports up to 8 cylinders for fuel and ignition and is ideal for compact, cost-effective installations.

Included:

  • Assembled Spark Gap X4 ECU

  • Harness-side connectors and pins

  • Arduino Mega 2560 "Pro" pre-flashed with latest Speeduino firmware

MAP Sensor:

⚠ Back-Order Notice (Estimated shipping time: 2–3 weeks as of November 14, 2025)
I’m currently waiting on a shipment of connectors, which has delayed final assembly of the next Spark Gap X4 batch. The connector delivery is estimated for November 21. Once they arrive, I’ll finish building and testing immediately. Orders should ship within 2–5 business days after the connectors are delivered.

Please note: Only new orders placed while this notice is active are affected by the back-order. All previous orders have already shipped.

Thank you for your patience. This one part is holding everything up, but the moment it lands, I’ll get these out the door.

—————————————————————————————

The Spark Gap X4 is a feature-filled 4-channel standalone ECU powered by the Atmega2560 and fully compatible with official Speeduino firmware. It supports up to 8 cylinders for fuel and ignition and is ideal for compact, cost-effective installations.

Included:

  • Assembled Spark Gap X4 ECU

  • Harness-side connectors and pins

  • Arduino Mega 2560 "Pro" pre-flashed with latest Speeduino firmware

Hardware Feature List:

  • Supports up to 8 cylinders fuel and ignition using 4 channels of fuel and 4 channels of ignition outputs, for 2 (Even fire only), 3, and 4-cylinder engines with full sequential fuel and ignition. 6 (even fire only) and 8-cylinder engines are supported with wasted spark and 2 squirts per cycle.

  • 4 x Fuel Injector Outputs

  • 4 x 5v Ignition outputs

  • 4 x Pre-configured analog input channels (CLT, IAT, TPS, O2 sensors)

  • 2 x Customizable spare analog inputs - e.g., oil pressure, fuel pressure

  • Up to 3 x Trigger inputs : Crank + dual camshaft position support

  • Up to 4 x Digital inputs - e.g., Flex Fuel, Vehicle Speed Sensor, Clutch switch

  • Dual VR conditioner mount (VR conditioner not included)

  • SMD MPXH-compatible mount (sensor options selectable above)

  • Barometric pressure sensor (real-time atmospheric compensation)

  • DRV8825 mount for stepper idle valve control

  • 8 x Digital Outputs (4 x 2A max | 4 x 400mA max) - e.g., Idle, Boost, VVT, Fuel Pump, Fan

  • Dedicated tachometer output

  • 2 x Serial headers (Serial0 & Serial3), ideal for Bluetooth or WiFi modules

  • USB-C header (automatically disables Serial0 when USB is connected)

Open Source and Customizable:

Full control with open-source hardware and firmware.

Affordable and Reliable:

Serious performance without the high price tag.

Backed by a Big Community:

Lots of guides, support, and real-world experience available.

Tested Before Shipping:

Every ECU is tested to ensure top quality and reliability.