Carburetor Spacer - 4150 1.5in Open L/W

The Carburetor Spacer – 4150 1.5in Open L/W by Wilson Manifolds is a precision intake manifold spacer designed for carbureted engines running Holley 4150-pattern carburetors. This component sits between your carburetor and intake manifold, providing critical tuning flexibility for street engines, drag cars, and performance builds. Whether you're chasing better idle quality, improved throttle response, or optimizing fuel distribution across cylinder banks, a carburetor spacer is an affordable yet effective modification that serious enthusiasts and tuners rely on.

The 1.5-inch height and open design work together to increase plenum volume, which dampens intake reversion and smooths air/fuel charge delivery—especially critical at part-throttle and idle transitions. The lightweight construction keeps inertial mass minimal, reducing heat soak and allowing your carb to breathe freely without the restrictive nature of solid spacers. Wilson Manifolds engineers this spacer with precision port matching to maintain flow characteristics, ensuring no turbulence is introduced at the carburetor base. The open design also facilitates easier carburetor removal and inspection without complete manifold disassembly, a practical benefit for ongoing tuning and maintenance.

This carburetor spacer is ideal for small-block and big-block builds where carburetor compatibility with Holley 4150 flanges is standard—think Chevy, Ford, and Mopar classic muscle cars as well as modern restomod projects. Installation is straightforward: remove your carburetor, unbolt the original gaskets, and sandwich the spacer between carb and manifold using existing studs and hardware. Weighing just 0.76 lbs and measuring 7.55 x 1.65 x 7.8 inches, it integrates seamlessly into tight engine bays. Pair this spacer with quality gaskets and a fresh carburetor tune-up for best results in any naturally aspirated, carbureted street or competition engine.