Manley LS1 E/D 1.575 Exhaust Valves 11681-8

If you're building a serious LS1 engine that demands reliability under extreme conditions, OEM exhaust valves won't cut it. Manley's Extreme Duty valves are engineered to withstand aggressive valve timing, high RPM operation, and sustained heat cycles that stock components simply can't handle. This is the difference between an engine that survives a season and one that thrives through years of hard use.

Built from premium stainless steel, these valves resist oxidation and thermal stress while maintaining precise tolerances. The 1.575-inch head diameter and 0.3136-inch stem are engineered for optimal flow characteristics and durability in LS-series applications. Installation is straightforward for anyone with cylinder head work experience, making this a smart upgrade for both street performance and race-focused builds.

• Extreme Duty construction
• Stainless steel material
• 1.575 in head diameter
• 0.3136 in stem diameter
• 4.923 in overall length
• GM LS-series fitment
• Set of 8 valves
• Manley MPN 11681-8