1-3/4in SBC Gasket D Port

The 1-3/4in SBC Gasket D Port by Schoenfeld is a precision exhaust header gasket engineered specifically for Small Block Chevy (SBC) applications requiring D-port cylinder head configurations. This gasket sits at the critical junction between your header primary tubes and cylinder head ports, sealing combustion pressure and preventing exhaust gas leakage that would compromise both performance and reliability. Whether you're building a street engine, a weekend cruiser, or preparing for track duty, a quality header gasket is non-negotiable—it's the often-overlooked foundation of any serious exhaust system upgrade.

Constructed with a steel core and graphite facings, the 1-3/4in SBC Gasket D Port delivers the durability and sealing integrity required for high-heat exhaust environments. The steel core provides structural rigidity under thermal cycling and vibration, while graphite facings conform to port irregularities and resist blowout under pressure spikes common in modified engines. The D-port configuration matches the larger, oval-shaped ports found on many vintage and performance SBC heads, with port dimensions of 1.460 x 1.680 inches—ensuring optimal alignment and complete combustion gas containment. This design minimizes gasket creep and maintains a dependable seal across repeated heat cycles, critical for engines producing elevated cylinder pressures or running extended rpm ranges.

Mechanics and engine builders installing aftermarket headers on SBC platforms—whether 283, 327, 350, or 400 cubic inch variants—rely on this gasket for leak-free exhaust sealing. Installation is straightforward: position the gasket between the header flange and cylinder head, align port openings, and torque fasteners in a progressive star pattern to ensure even clamping load. The compact weight and thin profile make handling and positioning simple, even in tight engine compartments. For anyone serious about maximizing header performance and preventing costly exhaust leaks, the Schoenfeld D-port gasket is the industry-standard choice.