Classic MegaSquirt Relay Board – Assembled

Simplify your MegaSquirt wiring with centralized power, relays, and fuse protection.

While not strictly required, the MegaSquirt Relay/Power Board offers a convenient and organized way to handle the power distribution and switching functions needed for your MegaSquirt ECU installation. This board is especially useful for carb-to-EFI conversions or custom builds where relay wiring needs to be added from scratch.

The relay board provides a central location for all essential relays, fuse protection, and wiring connections. It reduces the risk of miswiring, speeds up your install, and is durable enough for under-hood mounting.

Ideal For:

• Carbureted-to-EFI conversions

• Clean, centralized wiring installs

• Reducing the complexity of manual relay setups

• Protecting circuits with easily serviceable fuses

Key Features:

• Supports relays for main ECU power, fuel pump, and Fast Idle (FIDLE)

• Durable PCB design, suitable for under-hood environments

• Includes DB37 connector for building your relay cable

• Includes half-case for protection and mounting

• Uses mini-ATO style fuses (not included) for easy serviceability

Recommended Starting Fuse Values:

• 20A – Main power

• 10A – Fuel pump

• 5A – INJ1 / INJ2 (4-cylinder)

• 7.5A – INJ1 / INJ2 (8-cylinder)

Note: Always size fuses based on your specific injectors, wiring, and load requirements. These are general starting points.

Compatible Accessories:

• Relay Cable – Connects the Relay Board to your MegaSquirt ECU via DB37

• Wire Bundle – Great for wiring injectors, sensors, and more to the Relay Board