Kibblewhite Valve Spring Kit for Honda, 0.450-Inch Lift (30-4021)

Upgrade your Honda valvetrain with the Kibblewhite Valve Spring Kit, Part Number 30-4021. Designed for boosted and turbocharged applications, this performance-oriented kit supports engines using high-performance camshafts with lift up to 0.450 inch. It is engineered to provide increased spring rates and greater high-lift compatibility than stock valve springs, helping maintain dependable valve control in demanding operating conditions.
The Kibblewhite 30-4021 kit combines Cr-Si (chromium silicon) alloy dual valve springs with precision CNC-machined retainers. Depending on the application configuration, the retainers are produced from titanium or heat-treated steel to deliver the strength and durability required for elevated engine speeds. The dual-spring design helps improve valvetrain stability at high RPM while supporting performance engine builds that require greater control than factory components can provide.
Feature: Application compatibility for boosted and turbocharged Honda engines. Feature: Supports camshafts with up to 0.450-inch valve lift. Feature: Increased spring rates compared with stock valve springs. Feature: High-lift compatibility for performance camshaft applications. Feature: Cr-Si chromium silicon alloy dual springs for improved high-RPM valvetrain control. Feature: CNC-machined titanium or heat-treated steel retainers for durable performance. Feature: Made in the USA. The Kibblewhite Valve Spring Kit is a practical choice for engine builders seeking upgraded valvetrain control and reliable component performance in high-output Honda applications.

Features:

• Compatible with boosted or turbocharged Honda applications

• Supports camshafts with up to 0.450-inch valve lift

• Increased spring rates compared with stock valve springs

• High-lift compatibility for performance camshafts

• Cr-Si chromium silicon alloy dual springs provide high-RPM valvetrain control

• CNC-machined titanium or heat-treated steel retainers

• Made in the USA

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