Manley 11593-8 Severe Duty Stainless Steel Exhaust Valve Big Block Chevy

The Manley 11593-8 Severe Duty exhaust valve is engineered for high-performance and racing Big Block Chevy engines.

Key Features:

• XH-428 stainless steel exhaust valve material - superior high-temperature strength
• 1.900-inch valve head diameter optimized for Big Block Chevy applications
• 0.3715-inch (3/8-inch) valve stem diameter for precise fitment
• 5.364-inch overall length (stock height)
• Chrome hardened valve tips for extended wear resistance
• Swirl polished finish for reduced friction and improved flow

Manley's Severe Duty series represents their signature achievement in performance valve technology. The proprietary XH-428 exhaust valve material offers nearly double the ultimate tensile strength of competitors at 1500°F, and in comprehensive fatigue testing at 40,000 psi and 1400°F, these valves reached 100 million cycles while competitive offerings failed at just 100,000 cycles. Designed for serious performance applications where valve float and extreme temperatures demand uncompromising reliability.