BBM Exhaust Gaskets

The BBM Exhaust Gaskets (Part Number 264080) are precision-engineered header and manifold gaskets designed for Mopar B and RB-series engine platforms. These graphite gaskets feature a 1.900 x 1.650 inch rectangular port configuration and ship as a matched pair, providing the critical seal needed between exhaust manifolds and cylinder heads to prevent exhaust leaks and maintain engine performance integrity.

Graphite gasket material offers proven reliability in high-temperature exhaust applications, resisting thermal cycling and maintaining a consistent seal across the operating temperature range typical of Mopar B and RB-series engines. The precise rectangular port dimensions ensure proper alignment and load distribution across the sealing surface, reducing the risk of blow-by and minimizing exhaust gas escape into the engine bay. Proper gasket sealing is essential for accurate oxygen sensor readings, catalyst efficiency, and overall engine tuning on both stock and modified powerplants.

These gaskets are intended for builders and owners restoring or servicing Mopar B and RB-series engines—whether 340, 360, 383, 400, 413, 426, or 440 variants. Installation during head removal, manifold service, or engine rebuild ensures a factory-correct seal that maintains peak performance and emissions compliance. The pair format eliminates the need to source gaskets separately for dual-manifold configurations.

Exhaust gasket selection matters because improper sealing leads to power loss, diagnostic trouble codes, and potential secondary damage to turbochargers or superchargers on modified engines. Quality OEM-equivalent gaskets from verified sources ensure the seal performs as intended throughout the engine's service life, making this a foundational component in any Mopar rebuild or exhaust system overhaul.