Fuel Line Adapter

The HOLLEY Fuel Line Adapter (HLY26-70) is an essential fitting for custom fuel system builds and carburetor upgrades where connection standardization is critical. Designed for mechanics and enthusiasts modifying carbureted engines or swapping fuel delivery systems, this straight adapter bridges two different inverted flare thread sizes, eliminating the need for costly custom hose fabrication or incompatible line routing. Whether you're installing a new fuel regulator, connecting legacy carburetors to modern fuel systems, or adapting between factory and aftermarket components, having the correct adapter on hand prevents leaks, pressure loss, and tuning complications.

This fuel line adapter features a straight configuration in brass construction, offering superior corrosion resistance and compatibility with both gasoline and ethanol fuel blends common in high-performance applications. The adapter converts from a 1/2-20 inch inverted flare female port to a 5/8-18 inch inverted flare male connection, allowing seamless integration between fuel rails, carburetors, and regulator outlets with different thread specifications. Brass material ensures durability under fuel system pressures while remaining easy to service; the natural finish resists oxidation better than plated alternatives. The compact 3.45 x 1.15 x 5 inch footprint and minimal 0.07 lb weight make installation straightforward in tight engine bay environments without adding unnecessary bulk or vibration concerns.

Carburetor enthusiasts, street rod builders, and fuel system restoration specialists benefit most from having this adapter in their parts inventory. It's indispensable when converting single-plane to dual-plane intake manifolds, upgrading fuel pressure regulation, or retrofitting EFI components into carbureted platforms. Ensure proper inverted flare fitting engagement during installation—over-tightening brass fittings risks thread damage and fuel seepage. Compatible with any fuel system using 1/2-20 and 5/8-18 inverted flare standards, this HOLLEY adapter delivers the reliability expected from a precision fuel system component in both street and strip applications.