OBD1 to FuelTech FT550 Adapter Harness – Logic Corrected – Integrated Expansion

OBD1 to FuelTech FT550 Conversion Adapter

This adapter harness provides a structured and corrected transition from factory OBD1 ECU systems to a FuelTech FT550 standalone ECU.

Designed to retain factory engine harness integrity while integrating standalone functionality, expansion capability, and modern ignition support.

This is not a repin sheet solution.
This is a complete interface harness.

Configuration Overview

• OEM OBD1 ECU receptacles (P28 / P72 / P75 style)

• Genuine FT550 ECU connectors

• Fully corrected signal logic

• Integrated adapter loom

• Prewired T1 crank and cam inputs

• CANbus prewired

• Coil-on-plug DTM ignition connector

• Integrated 12-pin FuelTech style breakout

• Built-in expansion breakout connectors

Designed to minimize chassis modification while enabling full standalone control.

12-Pin Breakout Integration

A dedicated 12-pin FuelTech-style breakout connector is integrated for:

• Ignition 12V feed

• 5V reference distribution

• Sensor power routing

• Expansion outputs

• Auxiliary I/O allocation

This eliminates loose pigtails and allows structured system expansion.

Ignition & Engine Position Support

• T1 crank and cam sensor configuration prewired

• Coil-on-plug DTM output connector integrated

• Clean conversion path from distributor-based OBD1 systems to modern coil control

Designed for high-performance and boosted applications requiring reliable engine position referencing.

CANbus Integration

CAN wiring is pre-configured for dash integration, data logging, and FT550 peripheral support.

No additional backbone wiring required for standard FT550 CAN deployment.

Intended Applications

• Turbo OBD1 Honda builds

• Distributor delete conversions

• Coil-on-plug upgrades

• Full standalone conversions

• High-output street and competition builds

Off-road use only.

Production Note

This adapter is built using a proven production layout developed in collaboration with an established K/Honda wiring manufacturer. The structure and pinout integrity are consistent with their documented design standard.