New Design Transfer Tube 4150/4175

The new design transfer tube 4150/4175 from Holley is a precision fuel delivery component engineered for carburetors that demand reliable, consistent fuel flow between the primary and secondary circuits. Built for serious carburetor tuning and high-performance engine builders, this aluminum transfer tube replaces worn or corroded originals that compromise fuel distribution consistency. Whether you're restoring a classic muscle car, upgrading an off-road machine, or dialing in a street-strip hybrid, fuel delivery accuracy directly impacts throttle response, idle stability, and part-throttle transition quality.

Manufactured from aluminum in natural finish, the new design transfer tube maintains lightweight construction while delivering the durability required in high-vibration engine environments. The tube's geometry is optimized to balance fuel flow velocity and minimize pressure drop across the carburetor's fuel circuits, ensuring secondary boosters fire at the precise moment primary venturi saturation occurs. This design eliminates flat-spot hesitation during acceleration and provides the crisp throttle response expected from properly tuned Holley 4150 and 4175 carburetors. The compact 7.05-inch length and minimal 0.03-pound weight integrate seamlessly into tight engine bay configurations without adding parasitic mass.

Carburetor builders, engine swap specialists, and vintage racing enthusiasts benefit most from upgrading to this new design transfer tube, particularly when rebuilding fuel delivery systems on 4150/4175 platform carburetors. Installation is straightforward—the tube connects fuel passages between primary and secondary circuits and secures with standard fasteners. Replace cracked, corroded, or original tubes when performing major carburetor rebuilds or when converting to modern fuel systems on classic vehicles. This single piece ensures your Holley carburetor delivers smooth, predictable fuel metering across the entire rpm range, from idle through wide-open throttle.