Rywire Honda B-Series OBD1 Tuck Budget Eng Harness w/OBD1 Dist/Inj/Alt/92-95 ECU Plugs (Adapter Req) - RY-B1-BASE - RYWRY-B1-BASE

The Rywire Honda B-Series OBD1 Budget Tucked Engine Harness (RY-B1-BASE) is a made-in-the-USA wiring solution built specifically for Honda and Acura enthusiasts performing an engine swap or wire-tuck on a B-series-powered chassis. Designed to clean up the engine bay while retaining full OEM-level functionality, this harness features Mil-Spec Teflon-coated wire rated to 200°C and comes with OBD1 (92–95) ECU connectors for the distributor, injectors, and alternator — making it a go-to choice for B-series swap builds running an OBD1 computer. Whether you're building a dedicated track car or a clean street machine, the RY-B1-BASE gives you a professionally engineered, 100% quality-tested harness at a budget-friendly price point.

Key Features & Benefits

• Mil-Spec Teflon-Coated Wire (200°C Rated): The same high-temperature wire used in Rywire's premium Mil-Spec harness line means this budget option still handles the heat of a performance engine bay without compromising wire integrity.
• Nearly Identical to the Full Mil-Spec Line: The primary differences between the Budget and Mil-Spec versions are the single black wire color and the use of expandable loom — the construction quality, connectors, and functionality remain the same.
• All-New Connectors, Pneumatically Crimped: Every connector is new and crimped with pneumatic heads to ensure an OEM-quality crimp every time, reducing the risk of intermittent connections or failures.
• White ID Labels on Every Connector: Each connector is tagged with a white identification label, making the installation process significantly easier — even for first-time harness installers.
• 100% Pin-to-Pin & Resistance Tested: Every harness is quality-checked pin to pin and resistance-tested before it leaves the shop, ensuring no voltage fluctuations or wiring faults out of the box.
• Chassis-Specific Sub-Harness (Modular Design): Each harness ships with a custom back-side sub-harness matched to the chassis you select. If you ever change chassis, you only need a new sub-harness — not an entirely new wire loom — saving money down the road.
• OBD1 ECU Plugs (A, B, D) Included: The harness is built around 92–95 OBD1 computer connectors. Aftermarket ECUs using OBD2 plugs and non-US OBD2 computers are also compatible (with adapter). Note: USDM OBD2 computers are not supported natively.
• Multiple Configurable Options: At order time, buyers can select chassis adapter type, injector adapters, alternator adapters, a charge harness option, VTEC oil pressure solenoid bolt, and a ground kit — letting you tailor the harness precisely to your build.
• Heavy Interference Circuits Protected: All heavy interference circuits are shielded with proper wire covering and grounded correctly, reducing the risk of electrical noise that can affect engine management.
• Warranty Coverage: Rywire harnesses are warranted and guaranteed to work. Note that harnesses are non-refundable once installed, so it's critical to confirm your options before ordering.

Specifications

• Part Number: RY-B1-BASE
• Brand: Rywire
• Wire Type: Mil-Spec Teflon-coated
• Maximum Heat Rating: 200°C
• ECU Connector Type: OBD1 (92–95) — Plugs A, B, D included
• Loom Style: Expandable loom, single black wire color
• Country of Manufacture: Made in the U.S.A.
• OBD2 Computer Compatibility: Aftermarket OBD2 and non-US OBD2 computers compatible via adapter; USDM OBD2 computers not supported; H22 and GSR stock computers not compatible

Harness Connector List

The RY-B1-BASE includes connectors for all critical B-series engine sensors and actuators:

• Oil Pressure Sending Unit
• Knock Sensor
• Intake Air Temperature (Intake Manifold Style)
• Oxygen Sensor (Primary 4-Wire)
• Alternator
• Injectors 1–4
• MAP Sensor
• TPS (Throttle Position Sensor)
• Idle Control Motor
• Electronic Speed Sensor
• Ground
• Fan Switch
• OBD1 Distributor Plugs
• Water Temperature Sending Unit (for Gauge Cluster)
• Reverse Lights
• Engine Coolant Temp
• Starter Signal
• VTEC Solenoid
• OBD1 ECU Plugs A, B, D
• Power Distribution Cap
• 2 Extra Wires

Fitment

The RY-B1-BASE is designed for Honda B-series engines and is compatible across a wide range of Honda and Acura chassis when paired with the appropriate chassis adapter (selected at time of order). Supported chassis options include:

• '84–'85 Civic / CRX
• '86–'87 Civic / CRX
• '88–'89 CRX / Civic DX / STD
• '88–'91 CRX / Civic Si / HF / EX
• '90–'91 CRX / Civic DX / STD
• '92–'95 Civic
• '96–'98 Civic
• '99–'00 Civic
• '90–'91 Integra (USDM)
• '92–'93 Integra GS / RS
• '92–'93 Integra GSR
• '94–'95 Integra
• '96–'99 Integra
• '00–'01 Integra
• '87–'91 Prelude
• Other / Custom / Race-Style (including Rywire Race Fuse/Relay Box V3 and PDM System configurations)

Important fitment notes: A chassis adapter is required for proper fitment — this is selected during the ordering process. The harness uses OBD1 (92–95) ECU plugs natively. If you are running an OBD2 computer, a computer plug adapter is required; however, USDM OBD2 stock computers are not supported. The H22 and GSR stock computers are also not compatible. Always confirm your engine, chassis, and ECU type before finalizing your options.

What's in the Box

• Rywire B-Series OBD1 Budget Tucked Engine Harness (main loom)
• Chassis-specific back-side sub-harness (matched to chassis selected at order)
• All connectors as listed in the harness connector list above (new, pneumatically crimped, white ID-labeled)
• Any optional add-ons selected at time of order (injector adapters, alternator adapters, charge harness, ground kit, VTEC solenoid bolt)

Why Buy from ThreePiece.us

• Free Shipping: Every order ships free — no minimum required.
• Affirm Financing: Break your purchase into manageable payments with Affirm financing, available at checkout.
• Expert Fitment Support: Our team has served 10,000+ customers and is available to help you confirm the right chassis adapter, injector adapter, and alternator adapter options for your specific build before you order. Call us at 813-535-5801 or email sales@threepiece.us.
• Regularly Stocked: The RY-B1-BASE is a regularly stocked product, so you won't face the long lead times associated with made-to-order items.

Frequently Asked Questions

Q: Do I need to order a chassis adapter separately, or is one included?
A: The chassis adapter (back-side sub-harness) is included with your harness — but you must select your chassis type from the dropdown menu when ordering. This sub-harness is custom-built for the chassis you choose and is what plugs the engine harness into your vehicle's interior/chassis connectors. If you ever swap chassis in the future, Rywire sells the back-side harness separately (by phone, for previous harness customers only).

Q: Will this harness work with my OBD2 ECU or a standalone aftermarket ECU?
A: The RY-B1-BASE is built with OBD1 (92–95) ECU connectors. USDM OBD2 stock computers are not supported. However, aftermarket ECUs that use OBD2-style plugs and non-US OBD2 computers can be used with an appropriate computer plug adapter. H22 and GSR stock computers are not compatible. If you're running a popular aftermarket ECU like Hondata or AEM, confirm the plug style with the ECU manufacturer before ordering.

Q: What's the difference between the Budget (RY-B1-BASE) and Rywire's full Mil-Spec harness?
A: Both use the same Mil-Spec Teflon-coated wire rated to 200°C, the same all-new connectors, the same pneumatic crimping process, and the same 100% pin-to-pin quality testing. The Budget harness differs in that it uses a single black wire color throughout and expandable loom rather than the color-coded, more aesthetically finished loom found on the Mil-Spec line. For builders focused on performance and reliability over show-car aesthetics, the Budget harness delivers the same core engineering at a lower price point.

Q: Can I add optional adapters or accessories to my order?
A: Yes. At time of order, you can add injector adapters (OBD1 to RDX, ID Grey, ID Black, or OBD1 to OBD2), an alternator adapter (OBD1 to OBD2), a charge harness for starter and alternator leads, a Ryti Titanium VTEC Oil Pressure Bolt, and/or a ground kit. Review the options carefully before placing your order, as the harness is non-refundable once installed. Our team at ThreePiece.us is happy to help you confirm which options are right for your build.