{"product_id":"manley-performance-chevy-lt-1-6-2l-1-590-inch-head-diameter-pro-flo-severe-duty-exhaust-valves-set-of-8","title":"Manley Performance Chevy LT-1 6.2L 1.590-Inch Head Diameter Pro Flo \u0026 Severe Duty Exhaust Valves (Set of 8)","description":"Manley Severe Duty® Valves deliver the ultimate in strength, reliability, and high-performance durability. Engineered for extreme gasoline engine temperatures, these valves are crafted from exclusive materials (XH-428 for exhaust and NK-844 for intake), offering unmatched tensile strength compared to competitive alloys. In fatigue testing at 40,000 psi and 1400°F, Manley exhaust valves endured 100 million cycles, while competitors failed after just 100,000, proving a 1,000× longer fatigue life. Each valve features chrome stems, hard tips, and swirl-polished underheads with fully machined combustion faces for superior airflow, efficiency, and wear resistance. Built for those who demand race-winning strength and precision, Manley Severe Duty® Valves set the industry standard for performance and endurance.\nManley Valve - Exhaust, Valve-S\/D LT1 6.2L 1.590, .3136 STEM.\n\u003cul\u003e\n  \u003cli\u003eSwirl polishing and machined faces improved airflow\/optimized efficiency\u003c\/li\u003e\n  \u003cli\u003eExotic alloys for superior tensile strength, reliability, and longevity\u003c\/li\u003e\n  \u003cli\u003eProven fatigue strength for extreme performance\u003c\/li\u003e\n  \u003cli\u003eChrome stems and hard tips enhance durability\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe Manley Performance Chevy LT-1 6.2L 1.590-inch head diameter exhaust valves are engineered for high-performance automotive applications where durability and reliability are critical. Crafted from exclusive alloys—XH-428 for exhaust and NK-844 for intake—these valves deliver unmatched tensile strength, making them ideal for extreme engine conditions. They are designed to withstand high temperatures and stress, ensuring consistent performance during demanding racing or high-output scenarios. Each valve features chrome stems for corrosion resistance, hardened tips for wear resistance, and swirl-polished underheads coupled with fully machined combustion faces that promote superior airflow and combustion efficiency. These features contribute to increased horsepower, improved fuel efficiency, and extended engine life, making them a preferred choice for professional racers and automotive enthusiasts alike. The proven fatigue strength of these valves has been tested to endure over 100 million cycles at 40,000 psi and 1,400°F, demonstrating their exceptional longevity compared to standard options. The set includes eight valves, providing a comprehensive solution for performance engine builds and upgrades. Whether you're restoring a classic muscle car or building a race-ready powertrain, the Manley Severe Duty valves set the industry standard for performance, durability, and precision. Their fully machined combustion faces and swirl-polished underheads optimize airflow, maximizing engine efficiency and power output. Designed specifically for Chevrolet LT-1 6.2L engines, these valves ensure a perfect fit and dependable performance in demanding automotive environments.\u003c\/p\u003e\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eSwirl polishing and fully machined faces for improved airflow and optimized engine efficiency\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eExotic alloys XH-428 and NK-844 for superior tensile strength, reliability, and longevity\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eProven fatigue strength with durability tested to 100 million cycles at high stress and temperature\u003c\/li\u003e\u003c\/ul\u003e\u003cul\u003e\u003cli\u003eChrome stems and hardened tips enhance valve durability and resistance to wear\u003c\/li\u003e\u003c\/ul\u003e\u003cstyle\u003etable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; }\u003c\/style\u003e\n\u003ctable class=\"productattributes\"\u003e\n\u003cthead\u003e\u003ctr\u003e\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbdoy\u003e\n\u003ctr\u003e\u003ctd\u003eAir Freight Prohibited: false\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eNot Carb Approved: false\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eLtl Freight Required: false\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eProp 65: Y\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003ePart Type: automotive\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eEpa: N\/A\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eCarb Acknowledgement Required: false\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eRegular Stock: t\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd\u003eUnits Per Sku: 1\u003c\/td\u003e\u003c\/tr\u003e\n\u003c\/tbdoy\u003e\n\u003c\/table\u003e\u003cbr\u003e","brand":"Manley Performance","offers":[{"title":"Default Title","offer_id":53605796872465,"sku":"12347-8","price":311.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/3830\/0689\/files\/c2008e4f5a51a63cc4bb171d46e63bb4.jpg?v=1780004832","url":"https:\/\/shoprenegade.com\/products\/manley-performance-chevy-lt-1-6-2l-1-590-inch-head-diameter-pro-flo-severe-duty-exhaust-valves-set-of-8","provider":"Renegade Speed by Renegade Racing \u0026 Performance","version":"1.0","type":"link"}