Wossner RSX Type-S & Civic Type-R K20 High Compression Forged Piston Kit Hard Anodised Crown

Wossner RSX Type-S & Civic Type-R K20 High Compression Forged Piston Kit Hard Anodised Crown

The Wossner K20 High Compression Hard Anodised Piston Kit is the ultimate internal upgrade for elite naturally aspirated (NA) Honda builds. Engineered specifically for the high-revving K20A2, K20Z1, and K20Z4 engines, these pistons increase the static compression ratio to a potent 12.0:1 or higher, significantly enhancing thermal efficiency and top-end power. This "Premium Plus" series features a professional Hard Anodised crown coating, which provides a ceramic-like thermal barrier to protect the piston against the extreme cylinder temperatures and pressures associated with high-RPM competition use.

Manufactured in Germany from high-silicon 4032-T6 forged aluminium, these pistons offer a superior strength-to-weight ratio while maintaining low thermal expansion properties. The Hard Anodising process does more than reflect heat; it toughens the ring grooves to prevent micro-welding—a common failure point in high-stress racing engines where the ring can fuse to the piston under intense load. Combined with Wossner’s signature Moly skirt coating for reduced friction and mirror-polished crowns for better heat distribution, this kit is designed for builders who refuse to compromise on longevity or performance.

Key Performance Features

• Extreme High-Compression Profile: Maximises naturally aspirated power and throttle response by increasing the engine's static compression ratio.

• Hard Anodised Crown Coating: Provides a high-tech thermal barrier that withstands intense heat and protects against surface erosion.

• Anti-Micro-Welding Protection: The anodised ring lands prevent ring-to-groove fusion, ensuring a perfect seal under extreme competition stress.

• Low-Expansion 4032-T6 Alloy: Allows for tighter, quieter piston-to-bore clearances and exceptional fatigue resistance compared to 2618 alloys.

• Moly-Coated Skirts: Reduces parasitic drag and internal wear, ensuring smoother operation through the entire i-VTEC rev range.

Technical Specifications

Why Choose Wossner?

Wossner is globally recognised as a pioneer in high-performance engine internals, with a heritage rooted in European motorsport and precision engineering. By owning and operating their own forging plant in Germany, Wossner maintains absolute control over the quality and consistency of their aluminium alloys. This vertical integration allows them to produce pistons that are lighter, stronger, and more thermally efficient than standard cast or mass-produced forged components. When you choose Wossner for your K20 build, you are installing a product trusted by world-class engine builders to deliver podium-winning performance and daily-driver reliability.