Manley Chevrolet Small Block Exhaust Valve Kit - 1.625in Head Dia. 4.936in O/A Length, 0.3415in Stem

Manley Performance is well-known for making strong internal engine components, especially for racing applications. This exhaust valve kit is a prime example, built for Chevrolet Small Block engines. These valves are crucial for controlling the flow of exhaust gases out of your engine's cylinders, and when they're not working right, you'll notice a big drop in power and efficiency.

This kit uses XH-428 material for the exhaust valves, which Manley says has nearly double the ultimate tensile strength at 1500°F compared to other common exhaust valve materials like EV-8. They've also been put through rigorous fatigue tests, enduring up to 100 million cycles at high temperatures and stress levels, far outlasting many competitor parts that failed much sooner. The valves feature chrome stems and hard tips for added durability, and the under-head areas are swirl-polished while the combustion faces are fully machined to help improve airflow and combustion efficiency.

This kit is designed for high-temperature gasoline engines and is a solid option if you're rebuilding or upgrading the top end of your Chevrolet Small Block. Make sure to check the manufacturer's installation instructions for proper fitment and any specific requirements for your engine build.