Jet Extension Kit

The Jet Extension Kit from MOROSO is engineered for carburetor tuning and fuel delivery optimization on high-performance engines. This compact yet essential kit serves mechanics and engine builders who demand precise control over jet sizing and needle positioning in Holley-style carburetors. Whether you're dialing in a street engine, competition platform, or custom build, the Jet Extension Kit provides the flexibility needed to achieve optimal air-fuel ratios without requiring full carburetor disassembly or replacement.

This extension kit allows you to adapt and adjust jet positioning within your carburetor's fuel bowl, extending the effective depth or reach of main jets and idle circuits. By enabling precise jet depth manipulation, the kit helps eliminate fuel starvation at high RPM or under heavy acceleration while preventing overly rich conditions at cruise. The lightweight design—weighing just 0.03 lbs—ensures negligible impact on overall carburetor weight while maintaining critical tolerances required for consistent fuel metering across varying engine loads and throttle positions.

Carburetor enthusiasts, bracket racers, and street performance builders benefit most from this kit when fine-tuning existing carburetors rather than investing in complete replacements. Installation requires basic carburetor knowledge and hand tools—no special equipment needed. The Jet Extension Kit works seamlessly with standard Holley carburetor platforms commonly found on muscle cars, hot rods, and modified pickup trucks. Before installation, verify jet compatibility with your specific carburetor model to ensure proper fuel metering and avoid tuning complications.