Big Block Chev Air Gap Dual Plane Intake Manifold Oval Port

Big Block Chev Air Gap Dual Plane Intake Manifold Oval Port

Designed to extract maximum power from carbureted Big Block Chevy builds, this Air Gap Dual Plane intake manifold is engineered for 396–502 CID engines with large oval-port cylinder heads (1975 and earlier). Its Hi-Rise race-style design keeps air and fuel flowing aggressively at high RPM, delivering a steady, evenly distributed mixture for enhanced mid-to-high end performance.

Key features

• Oval-port runners tuned for large oval-port cylinder heads, optimizing airflow on 396–502 CID Big Block Chevys
• Natural cast finish with a square bore carburetor pad, compatible with aftermarket square-bore carburetors — manual or electric choke options apply
• Non-EGR configuration to preserve airflow and power delivery
• RPM operating range: 1500 to 6500, ideal for both street and high-performance applications
• Hi-Rise race-style manifold designed for high RPM and large displacement engines
• Carburetor mounting pad accepts spacers and aftermarket carbs; dual distributor hold-downs for secure, race-ready installation
• Four corner water ports plus a fifth water outlet at the front facilitate robust cooling integration
• Engineered to keep intake air cooler and fuel delivery consistent, helping you squeeze every horsepower from your carbureted BB Chevy setup
• Supports late-model water necks, air conditioning, alternator, and HEI ignition systems in most installations, making it versatile for retrofits and rebuilds

Fitment and installation notes

• Fitment: Big Block Chevy engines from 396 to 502 CID
• Specifically compatible with large oval-port cylinder heads from 1975 and earlier, ensuring proper alignment and flow for peak power across the stated RPM range
• To achieve optimal performance, port-match the intake runners to your cylinder heads and ensure a precise fit for best air/fuel distribution

Performance advantages

• Hi-Rise design supports high RPM operation and large displacement, delivering strong mid-range and top-end power
• Oval-port tuning enhances airflow efficiency on engines using large oval-port heads, contributing to more consistent fuel delivery and combustion
• Non-EGR configuration maintains maximum airflow, helping preserve horsepower on carbureted BB Chevy builds