Manley Chevrolet Big Block Exhaust Valve Kit - 1.900in Head Dia. 5.364in O/A Length, 0.3715in Stem

Manley Performance is well-known for making strong internal engine components, especially for racing applications. This exhaust valve kit is a prime example, designed for Chevrolet Big Block engines. These valves are crucial for managing the hot exhaust gases leaving your cylinders, and Manley has put a lot of thought into making them last under tough conditions.

The exhaust valves in this kit are made from XH-428 material, which Manley states has nearly double the tensile strength at high temperatures compared to other common exhaust valve materials like EV-8. They've also been put through rigorous fatigue testing, enduring up to 100 million cycles at 1400°F, which is a notable improvement over many competitor parts that failed much sooner. The stems are chrome-plated for added durability, and the under-head areas are swirl-polished to help improve airflow out of the combustion chamber.

This kit is specifically designed for high-temperature gasoline engines. The valves measure 1.900 inches across the head diameter and are 5.364 inches overall in length, with a 0.3715-inch stem diameter. If you're rebuilding the top end of a performance Chevrolet Big Block and need exhaust valves that can handle the heat and stress, these are a solid option.