Rywire RY-B-SUB-EF Adapter Harness for 88-91 Honda Civic/CRX

Vehicle Fitment

• 1988-1991 Honda Civic/CRX (Si, HF, EX, Base, DX, LX, RT 4WD)

Features

• Chassis-specific adapter harness for engine wiring integration
• Designed for use with Rywire Budget B-Series engine harness
• Direct fit for 88-91 Honda Civic and CRX platforms
• Improves reliability over factory connectors in swap applications
• High-quality terminals and connectors for secure signal paths
• Color-coded wiring for easier installation and routing
• Compatible with popular aftermarket ECUs and harness setups
• Ideal for performance builds and engine swaps requiring adapter interface

Specifications

• Brand: Rywire
• Part Number: RY-B-SUB-EF
• Application: Chassis specific engine harness adapter
• Connector type: Vehicle chassis side to engine harness interface
• Material: Automotive-grade wiring and molded connectors
• Fitment years: 1988, 1989, 1990, 1991
• Compatible trims: Civic Base, DX, LX, Si; CRX HF, Si; Civic RT 4WD, EX
• Electrical role: Adapter between OEM chassis wiring and performance harness

Included Components

• 1x Rywire RY-B-SUB-EF chassis specific adapter harness
• 1x Set of connector seals and terminals as required

Product Description

The Rywire RY-B-SUB-EF Adapter Harness is a chassis-specific wiring interface designed to bridge the gap between your vehicle's factory wiring and an aftermarket or performance B-Series engine harness. Built for 1988-1991 Honda Civic and CRX models (including Si, HF, EX, Base, DX, LX and related trims), this adapter simplifies wiring during engine swaps and upgrades by providing a direct plug-in connection without cutting or splicing into the stock harness.

Constructed with automotive-grade wiring and molded connectors, the harness helps ensure reliable signal integrity and fitment in demanding applications. Whether you're installing a Rywire budget B-Series harness or integrating into a modified electrical system with an aftermarket ECU, this adapter harness reduces installation time and improves engine bay organization. Designed for performance enthusiasts and professional builders alike, it's an essential component for B-Series turbo, naturally aspirated, or street build projects using 88-91 Civic/CRX platforms.