Mopar 6.4L Hemi R/M 1.675 Exhaust Valves

The Mopar 6.4L Hemi R/M 1.675 Exhaust Valves from Manley represent the gold standard for high-performance Gen III Hemi engine builds. Designed specifically for serious enthusiasts and professional engine builders tackling race-level power output, this set of eight stainless steel exhaust valves delivers the precision engineering required to maximize airflow and sustain extreme combustion pressures. Whether you're building a competition 6.4L for drag racing, road course duty, or street performance, these valves are engineered to handle the demands of forced induction, nitrous, or naturally aspirated builds pushing near or beyond factory limits.

Each valve features a 1.675-inch head diameter with a 0.312-inch valve stem and extends 5.100 inches in overall length, matching original Mopar Gen III Hemi specifications while offering superior metallurgy over stock components. The stainless steel construction provides exceptional heat resistance and corrosion protection—critical for race environments where exhaust temperatures routinely exceed 1,800°F. The larger head diameter and precision stem tolerances minimize turbulence during the exhaust stroke, improving scavenging efficiency and reducing back-pressure. Manley's race-series valves are manufactured to exacting tolerances with hardened seating surfaces, ensuring consistent performance across multiple heat cycles and extended engine runtime without degradation.

These exhaust valves are essential for anyone building a stroker or high-displacement 6.4L Hemi for maximum power output. Professional engine builders and experienced DIY technicians installing these valves should pair them with corresponding intake valves, quality valve seats, and precision valve guides to achieve proper sealing geometry and longevity. The set of eight is sufficient for one complete engine build (four valves per cylinder × two cylinders). Compatible with all Gen III Hemi platforms including Dodge, Chrysler, and Jeep applications, these Manley valves ensure your investment in engine internals delivers both reliability and peak performance potential.