Header Flange Kit - SBC 3/8 Thick

The Patriot Exhaust Header Flange Kit for Small Block Chevy features a robust 3/8-inch thick steel construction designed to seal the junction between your exhaust headers and cylinder head. This pair of flanges is machined to accommodate 1.5 x 1.84-inch oval ports, providing a precise fitment that minimizes exhaust leakage and maximizes scavenging efficiency. The 3/8-inch thickness delivers the structural rigidity necessary to withstand thermal cycling and vibration inherent in high-performance engine operation.

SBC header flange kits are critical components in exhaust system assembly, especially when upgrading from factory manifolds or replacing corroded original equipment. The oval port configuration matches the flow characteristics of aftermarket performance headers optimized for small block Chevy applications. Steel construction ensures durability across repeated heat cycles—essential for vehicles running naturally aspirated or forced induction builds. The 3/8-inch spec balances port sealing integrity with weight and machinability, representing the industry standard for this class of flange.

This header flange kit is suited for engine builders, restoration specialists, and performance enthusiasts restoring or upgrading small block Chevy powerplants. Whether you're fabricating a custom exhaust system, replacing worn flanges on existing headers, or ensuring correct fitment on new headers, matched pairs eliminate guesswork and guarantee symmetrical port alignment. The kit's proven specifications make it compatible with most common SBC header designs across generations and applications—from street engines to track builds.

Patriot Exhaust is a recognized manufacturer of OEM-style and performance exhaust components, with header flanges representing a foundational component in their product range. Purchasing flanges in matched pairs ensures consistent sealing and simplifies inventory management for shops and builders managing multiple projects.