289-351W Ford 5L Square Port Header Gaskets

The HEDMAN 289-351W Ford 5L Square Port Header Gaskets are precision-engineered exhaust gaskets designed for small block Ford applications with square port cylinder heads. Supplied as a pair, these gaskets seal the critical junction between the exhaust header and the engine block, preventing exhaust leaks that compromise performance and increase underhood temperatures. Built to handle the thermal and pressure cycling inherent to high-performance and street applications, square port gaskets are the correct choice for 289, 302, and 351W Ford engines equipped with casting-specific square port heads.

Header gasket selection is critical for engine longevity. Incompatible gaskets or improper port configuration can result in persistent exhaust leaks, loss of scavenging efficiency, and accelerated corrosion at the header-to-block interface. The square port design of these HEDMAN gaskets is engineered to mate precisely with the port casting geometry of compatible 289, 302, and 351W heads, ensuring a complete seal across the entire exhaust passage. Proper gasket engagement eliminates hot spots and maintains optimal exhaust flow dynamics in both naturally aspirated and forced induction small block Ford engines.

These gaskets address a common pain point in Ford engine builds: identifying and sourcing the correct gasket profile for your specific head casting. Round port and square port Ford cylinder heads require different gasket profiles; using the wrong type results in poor sealing and gas escape. This pair is purpose-built for square port applications and should be verified against your cylinder head casting before installation. Supplied in a pair to cover both sides of the engine, they're an essential component for any 289-351W header installation, rebuild, or gasket replacement on small block Ford platforms.