Manley Chevrolet Small Block Exhaust Valve Kit - 1.625in Head Dia. 5.036in O/A Length, 0.3415in Stem

Manley Performance is well-known for making strong internal engine components, and their Severe Duty? Exhaust Valves are a prime example of that commitment. If you're rebuilding a high-temperature gasoline engine, especially for performance or racing applications, these valves are built to handle the stress. They are specifically designed for Chevrolet Small Block engines and feature a 1.625-inch head diameter, a 5.036-inch overall length, and a 0.3415-inch stem diameter.

These exhaust valves are crafted from XH-428 material, which Manley states has nearly double the ultimate tensile strength at 1500°F compared to other common exhaust valve materials like EV-8. They've also undergone rigorous fatigue testing, enduring up to 100 million cycles at 40,000 psi and 1400°F, a notable improvement over competitor parts that failed much sooner. The valves also feature chrome stems and hard tips for added wear resistance, and the under-head areas are swirl-polished to help improve airflow into the combustion chamber.

This kit includes the exhaust valves, and Manley also offers matching intake valves made from their NK-844 material. When rebuilding your engine, using matched, high-performance components like these valves can make a significant difference in reliability and performance under demanding conditions.