Flex Fuel Fittings 3/8 "GM Spring Lock" to -6AN Male

Overview

Purpose-built flex fuel sensor fittings that solve the connection headache between GM-spec ethanol content sensors and proper AN fuel lines. Essential for any E85-capable build where reliable fuel composition monitoring is critical for safe tuning and engine protection.

Technical Specifications

• Part Number: HT-011030
• Connection Type: 3/8" GM Spring Lock to -6AN Male
• Thread Standard: -6AN (9/16-18 UNF)
• Quantity: Two fittings per kit
• Material: Anodised aluminium construction

Why You Need This

Flex fuel sensors are becoming standard kit on serious turbo builds running E85 blends, but connecting them properly often stumps builders. GM's spring-lock fuel system uses a completely different connection standard to the -6AN lines most performance builds demand. Bodge it with rubber hose and jubilee clips, and you're asking for fuel leaks, pressure drops, or worse — inaccurate ethanol readings that could lean out your engine on a dyno pull.

These purpose-made adapters give you the proper engineered connection between your flex fuel sensor and -6AN fuel rail or return lines. We see them constantly on LS swap projects, particularly in drift cars and track builds where E85's octane advantage is crucial. The spring-lock side clicks securely onto the sensor outlet, whilst the -6AN male thread accepts any standard AN hose end or fitting. Two fittings per kit handles both inlet and outlet connections on most flex fuel sensor installations.

ECU & System Compatibility

Works with any Haltech ECU equipped with flex fuel sensor inputs — Elite 550, 750, 1000, 1500, 2000, and 2500 models all support flex fuel monitoring when paired with appropriate sensors. Also compatible with Nexus R3 and R5 ECUs. Contact our technical team to confirm the best sensor and wiring approach for your specific Haltech setup.

What's in the Box

• Two 3/8" GM Spring Lock to -6AN Male adapter fittings
• Installation hardware

Complete Your Build

Most customers fitting these adapters need a complete flex fuel sensor and the appropriate Haltech wiring harness to complete their ethanol content monitoring system. We stock the full range of GM-compatible flex fuel sensors and Haltech sensor extension looms in our UK warehouse. Our technical team can advise on the complete package needed for your application — whether that's an LS-swapped S-body, turbocharged Honda build, or rotary conversion running serious ethanol content. Call us before ordering to ensure you get everything needed for a proper first-time installation.