Air Cleaner Adapter Stud

The MOROSO Air Cleaner Adapter Stud (MPN 66390) is a precision threaded adapter designed to bridge mismatched intake manifold and air cleaner mounting threads. This steel stud converts a 5/16-18 inch male thread to a 1/4-20 inch female thread, measuring 0.875 inches in length with a zinc-plated finish for corrosion resistance. It solves a common engine bay compatibility issue when upgrading or restoring intake systems with non-standard configurations.

The zinc-plated steel construction provides durable protection in the engine bay environment, where moisture and temperature cycling can corrode unfinished hardware. The dual-thread design accommodates both SAE and metric fastening standards, eliminating the need for custom drilling or manifold rework. At just 0.04 pounds, the minimal weight and compact 0.875-inch length ensure it installs cleanly without adding bulk to the intake system or requiring modifications to surrounding components.

This adapter is essential for engine builders, restoration shops, and performance enthusiasts working with classic or modern small-block applications where aftermarket air cleaners or carburetors have different mounting patterns than factory equipment. Whether you're transitioning from original manifold hardware to contemporary intake components or working with mixed fastener standards during an engine rebuild, this adapter provides a straightforward mechanical solution that maintains proper clamping force and alignment.

MOROSO is recognized for precision engine accessories and fastening solutions trusted in high-performance applications. This stud is an individual unit, allowing you to purchase exactly the quantity needed for your intake configuration without excess inventory.