Skunk2 Alpha Valve Spring Set – D15/D16 SOHC VTEC

The Skunk2 Alpha Valve Spring Set for Honda D15 and D16 SOHC VTEC engines is engineered to deliver unmatched valvetrain stability, allowing your engine to rev safely beyond 10,000 RPM. Designed, developed, and tested entirely in-house, Skunk2’s Alpha Valve Springs are the result of years of high-performance engine building and motorsport experience.

Constructed from super-clean chrome-silicone wire sourced from Japan, these valve springs are precision wound, heat-treated, and shot-peened for maximum durability. Each spring is carefully tested on both the dyno and track to ensure reliable performance under extreme conditions—from high-RPM drag racing engines to endurance builds.

Ideal for naturally aspirated or forced-induction setups, these springs eliminate valve float and maintain consistent valve control across the entire RPM range, making them an essential upgrade for any serious SOHC VTEC build.

Key Features:

• Prevents Valve Float – stable beyond 10,000 RPM

• Chrome-Silicone Construction – high tensile strength and long-term reliability

• Manufactured from Premium Japanese Wire – milled to tight tolerances

• Shot-Peened and Heat-Treated – improved fatigue resistance

• Dyno and Track Tested – proven in 11,000 RPM drag engines and 17,000 RPM superbikes

• Optimized for Naturally Aspirated and Forced-Induction Engines

• Direct Drop-In Fitment – compatible with OEM retainers or Skunk2 titanium retainers

Technical Specifications:

• Seat Pressure: 62 lbs @ 1.400”

• Open Pressure: 158 lbs @ 0.900”

• Material: Chrome-Silicone Alloy (Japan Milled)

• Max RPM: 10,000+

• Configuration: Dual Valve Springs

• Coil Bind Clearance: Optimized for high-lift camshafts

Performance Benefits:

• Maintains valvetrain stability at extreme RPMs

• Reduces risk of valve float and bounce

• Enhances power delivery at high engine speeds

• Suitable for both street and race applications

• Extends valvetrain life under demanding conditions

Vehicle Fitment:
Compatible with:

• Honda D15 SOHC VTEC Engines

• Honda D16 SOHC VTEC Engines (D16A, ZC, etc.)

Common applications include:

• Civic EX / Si (D16Z6, D16Y8)

• CRX Si (SOHC VTEC swaps)

Included:

• (1) Complete Set of Alpha Valve Springs (16 total)

• Installation Instructions