Wossner Civic D16Z6/Z7/Z9 11.5:1 Compression Forged Piston Kit

Wossner Civic D16Z6/Z7/Z9 11.5:1 Compression Forged Piston Kit

The Wossner Civic D16Z6/Z7/Z9 11.5:1 High Compression Forged Piston Kit is the ultimate internal upgrade for Honda D-Series enthusiasts looking to maximise naturally aspirated power. By increasing the compression ratio from the factory 9.2:1 to a potent 11.5:1, these pistons significantly improve thermal efficiency and throttle response. This setup is specifically designed for the high-revving SOHC VTEC engines found in the Civic EX, Si, and Del Sol, providing the structural foundation needed for aggressive cam profiles and high-RPM competition.

Each piston is precision-forged in Germany from 4032-T6 aluminium alloy, a high-silicon material renowned for its incredible strength and low thermal expansion. This allows engine builders to maintain tighter piston-to-bore clearances, resulting in a quieter engine and reduced oil consumption compared to other forged brands. To further enhance performance, Wossner applies a signature Moly skirt coating to reduce internal friction and mirror-polishes the crowns to reflect heat and prevent the hot spots that can lead to detonation.

Key Performance Features

• High-Compression 11.5:1 Profile: Engineered to extract maximum power and torque from naturally aspirated D16Z-series engines.

• 4032-T6 Forged Aluminium: Offers superior fatigue resistance and minimal expansion for excellent longevity and cold-start performance.

• Friction-Reducing Moly Coating: Advanced skirt treatment minimises parasitic drag, ensuring more power reaches the wheels.

• Mirror-Polished Crowns: Hand-finished to eliminate sharp edges and carbon buildup, improving combustion stability at high compression.

• Complete Racing Kit: Includes four forged pistons, a high-performance Japanese ring set, 19mm gudgeon pins, and heavy-duty circlips.

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 Honda D16 build, you are installing a product trusted by world-class engine builders to deliver podium-winning performance and daily-driver reliability.