Manley Chevrolet Big Block Exhaust Valve Kit - 1.880in Head Dia. 5.464in O/A Length, 0.3715in Stem

This kit includes Manley's Severe Duty? exhaust valves for Chevrolet Big Block engines. These valves are specifically made from XH-428 material, a choice that stands out globally for its strength at high temperatures. They feature chrome stems and hard tips, adding to their durability and making them a solid option for rebuilding or upgrading your engine's top end.

Manley put these valves through some serious testing. Under normal operation, engine valves deal with a lot of stress, especially when they bounce off the seat. These Manley exhaust valves were tested at 40,000 psi and 1400?F, and they held up for an impressive 100 million cycles. That's a lot more than what many other valves can handle, showing how well they're built for demanding use. The under-head areas are swirl polished and the combustion faces are fully machined, which helps improve airflow and how efficiently the engine burns fuel.

If you're working on a high-temperature gasoline engine, these valves are designed to perform. The XH-428 material used for the exhaust valves has nearly double the strength at 1500?F compared to other common exhaust valve materials like EV-8. For intake valves, Manley uses NK-844, which has over four times the strength of competing intake valve materials at 1000?F. This makes them a well-built choice for engines that run hot.