Skunk2 311-05-7350 Pro Series XP Racing Valve Springs for Honda B-Series

Vehicle Fitment

• Designed for Honda B-Series VTEC engines (B16/B17/B18) in performance applications
• Common swaps include Honda Civic Si/Del Sol VTEC and Acura Integra GS-R/Type R

Features

• Pro Series XP (Extra Pressure) dual racing valve spring set
• Higher seat pressure for turbocharged or high-rpm builds
• Prevents valve float at very high engine speeds
• Designed to support extreme lift camshafts
• Manufactured from premium chrome-silicone wire milled in Japan
• Heat-treated, shot-peened and chemically polished for durability
• Enhances valvetrain stability beyond standard springs
• Tested on dyno, street, and track environments

Specifications

• Part Number: 311-05-7350
• Spring Type: Dual valve spring set
• Seat Pressure: 93 lbs @ 1.320" installed height
• Open Pressure: 238 lbs @ 0.820"
• Coil Bind Height: 0.718"
• Quantity: Set of 16 dual springs (covers one cylinder head)
• Material: Chrome-silicone performance wire
• Application: High-rpm/forced induction B-Series engines

Included Components

• 1x Set of 16 Skunk2 Pro Series XP dual valve springs

Product Description

The **Skunk2 311-05-7350 Pro Series XP Racing Valve Springs** are high-pressure performance valve springs engineered for **Honda B-Series VTEC engines** - including B16, B17, and B18 variants - that are built for high-rpm or forced induction use. These Pro Series "XP" valve springs feature elevated **seat pressure and robust open pressure** to maintain control of the valvetrain at extreme engine speeds, helping prevent valve float and ensuring stable operation with aggressive cam profiles.

Constructed from **premium chrome-silicone wire milled in Japan** and finished with heat treating, shot peening, and chemical polishing, these springs offer improved durability, enhanced resistance to load loss, and reliable performance in racing, street, and dyno-tested environments. They're suited for performance Honda builds such as Civic Si and Del Sol VTEC engines or Acura Integra GS-R/Type R applications where valvetrain stability at high rpm is essential. Installation may require specific spring bases for some engines (e.g., H22A/F20B).