BBM R/M 1.810in Exhaust Valves

The Manley BBM R/M 1.810-inch exhaust valves are precision-engineered performance components purpose-built for high-output Mopar RB-series engine applications. This set of eight stainless steel valves features a 1.810-inch head diameter and 0.342-inch valve stem, delivering the thermal stability and flow characteristics required for sustained high-RPM operation and elevated boost conditions.

Manley exhaust valves are manufactured from premium stainless steel alloy formulations selected to withstand sustained exposure to combustion heat and exhaust gas velocity without thermal distortion or seating degradation. The 1.810-inch diameter specification is engineered to match the intake valve diameter found in modern RB-series cylinder head castings, optimizing the volumetric efficiency and scavenging characteristics across the engine's operating range. The 0.342-inch stem diameter maintains compatibility with OEM valve guides while providing the rigidity needed under high-lift, high-duration camshaft profiles.

These valves are specified for street and competition builds where factory exhaust valve metallurgy cannot sustain the thermal loading imposed by aggressive power adders or extended wide-open-throttle duty cycles. OEM RB-series valves often fail prematurely under turbocharger or supercharger boost, heavy nitrous oxide enrichment, or high-compression naturally aspirated builds. Manley valves address this failure mode through superior heat treat and alloy composition, extending valve and seat life across the rebuild interval.

RB-series engine packages span Dodge B-body performance platforms from the 1960s through the early 2000s, including street 440 and 413 builds, race-spec big-block configurations, and modern restorations with contemporary fueling and ignition. Verify your specific cylinder head casting and valve seat machining before ordering to ensure proper seating geometry and stem clearance.