Manley Chevrolet Small Block Exhaust Valve Kit - 1.625in Head Dia. 5.240in O/A Length, 0.3110in Stem

Manley Performance is known for making well-built engine components for racing and high-performance applications. This kit features their Severe Duty? exhaust valves, specifically designed for Chevrolet Small Block engines. These valves are crucial for managing the exhaust gases from your cylinders, and Manley's design focuses on extreme durability and performance under demanding conditions.

These exhaust valves are made 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, which is significantly longer than many competing valves. The valves feature chrome stems and hard tips for added wear resistance, and the under-head area is swirl-polished to help improve airflow and combustion efficiency.

This kit includes eight exhaust valves, each measuring 1.625 inches across the head diameter and 5.240 inches overall length, with a 0.3110-inch stem diameter. They are designed for high-temperature gasoline engines and are a solid option if you're rebuilding or upgrading the top end of your Chevrolet Small Block.