Bourne HPP Inlet Valve Spring Honda K20 K24

Bourne HPP K-Series High Performance Inlet Valve Spring Set

Optimize the breathing of your engine with this premium performance inlet valve spring set, developed by Bourne HPP. Designed to support high-performance cylinder head configurations, these springs offer a critical upgrade for builds pushing beyond factory power limits, ensuring precise valve control during the intake stroke.

Engineered for versatility, these inlet springs are rated to handle between 350-700 HP in boosted applications and 200-350 HP in naturally aspirated setups. Despite their enhanced capabilities, they are designed for standard fitment, allowing for a straightforward installation using the original platform shims and retainer setups.

Key Specifications

• Fitment: K20 (Inlet Side)

• Material: EN 10270-2 SiCr (Silicon Chrome)

• Wire Diameter: 4.10mm

• Outside Diameter: 29.90mm

• Inside Diameter (Min): 21.70mm

• Free Length: 49.61mm

• Solid Length: 25.83mm

Performance Pedigree

These springs are manufactured from high-grade Silicon Chrome alloy (SiCr), selected for its superior fatigue resistance and ability to maintain consistent pressure over time. Whether you are building a high-compression N/A track car or a turbocharged street monster, these springs provide the necessary seat pressure to prevent valve float and ensure maximum airflow efficiency at high RPMs.

Kit Contents

• 8x Bourne HPP Inlet Valve Springs

Installation Note: Please note that these are sold in a pack of 8, which covers the inlet side of a standard K-Series cylinder head. When installing, it is critical to verify installed heights and check for coil bind to ensure proper clearance. We recommend professional installation and measurement.