4in Inline Air Box

The SPECTRE 4in Inline Air Box (SPE-9832) is a precision-engineered intake component designed for enthusiasts and mechanics seeking improved engine breathing and performance gains. This compact inline air box replaces restrictive factory intake systems, offering a direct path for cooler, denser ambient air to reach your engine's carburetor or fuel injection system. Whether you're running a street car, weekend warrior, or performance build, this 4-inch diameter design provides measurable airflow advantages without requiring extensive engine bay modifications.

Built with SPECTRE's track record for quality automotive components, the 4in inline air box features a streamlined internal passage that minimizes turbulence and flow restriction compared to multi-bend factory designs. The compact 6.7 x 6.7 x 12.15-inch footprint allows versatile engine bay placement, while the 4-inch inlet diameter matches common carburetor and throttle body mounting standards. At just 2.925 pounds, it adds negligible weight while reducing heat soak—a critical factor when cooler intake charge temperatures directly translate to denser fuel-air mixture and measurable horsepower gains, especially in naturally aspirated engines.

Best suited for street performance, bracket racing, and classic car restoration projects, this inline air box serves both bolt-on builders and dedicated engine builders looking to optimize intake efficiency. Installation typically involves basic hand tools and familiarity with intake plumbing—most applications require custom ducting or adapter brackets to mate with your specific carburetor or fuel injection setup. Verify 4-inch inlet compatibility with your intake manifold before purchase; consult detailed fitment guides or reach out to experienced builders familiar with your engine platform for seamless integration.