2-7/8 FLANGE 4in.DIA 6in

The 2-7/8 FLANGE 4in.DIA 6in by K AND N ENGINEERING is a premium intake air filter adapter designed for builders and enthusiasts who demand precision-engineered components for custom intake manifold construction. This flanged coupling serves as a critical transition piece in high-performance air intake systems, enabling seamless ducting between filter housings and carburetor or fuel injection throttle bodies. Whether you're fabricating a cold-air intake for improved volumetric efficiency or assembling a custom intake manifold, this adapter provides the structural integrity and precise fit required for reliable engine operation.

Engineered with K AND N's commitment to quality, the 2-7/8 flange diameter accommodates standard 4-inch diameter intake ducting while the 6-inch length provides adequate material for secure mechanical attachment and welding or clamping. The robust construction minimizes vibration transmission from the intake tract to the engine bay, reducing resonance noise and supporting consistent fuel delivery calibration in tuned systems. Its aluminum or steel composition (depending on application-specific variants) resists corrosion from moisture ingestion and maintains dimensional stability across engine operating temperatures, ensuring repeatable airflow characteristics essential for carburetor or EFI tuning.

This adapter is ideal for street rod builders, engine swap technicians, and performance enthusiasts constructing custom intake configurations where OEM ducting components are unavailable or incompatible with engine modifications. Installation requires basic mechanical assembly tools and knowledge of intake manifold port matching—no specialized equipment necessary. The lightweight design (0.8 lbs) minimizes underhood weight addition, making it suitable for both naturally aspirated and forced-induction applications where intake tract optimization directly impacts power delivery and throttle response.