Manley 221421-1 NexTek Dual Valve Spring 1.324" OD GM LS

The Manley 221421-1 NexTek high-performance valve spring is engineered for demanding performance and racing applications, particularly GM LS-series engines. This dual valve spring configuration delivers precise valve control and exceptional durability under extreme conditions.

Key Specifications:

• Outside Diameter: 1.324 inches
• Inner Spring I.D.: 0.676 inches
• Outer Spring I.D.: 0.920 inches
• Spring Rate: 435 lbs/in
• Installed Height: 1.800 inches at 165 lbs pressure
• Open Height: 1.000 inches at 515 lbs pressure
• Maximum Valve Lift: 0.800 inches
• Coil Bind: 0.900 inches

Advanced Engineering Features:

• Manufactured from super-clean, high-tensile chrome silicon steel
• Shot-peened to MIL specifications for maximum fatigue life
• Proprietary multi-step heat-treating process minimizes load loss
• Computer-aided modeling reduces valve bounce and valve gear separation
• Fully polished finish reduces friction and improves fatigue life
• Extended tip thickness eliminates overload breakage
• Tightly controlled open-end flatness reduces valve stem side loading

Manley NexTek valve springs represent state-of-the-art valve spring technology, featuring smaller diameter and lightweight construction that allows engines to rev higher faster. Ideal for street performance, bracket racing, and professional motorsports applications. Sold individually.