Wiseco K623M845 Forged Piston Kit for 1989-2001 Honda B16 / B18

Vehicle Fitment

• Honda B16A engines (e.g., Civic Si 1993-2001)
• Honda / Acura B18 engines (e.g., Integra, LS/GS/Type-R, 1989-2001)
• Honda B20B / B20Z with VTEC head applications

Features

• Forged 2618 aluminum for high strength and performance
• ArmorGlide® low-friction skirt coating to reduce wear
• Flat-top crown design for optimized compression and pistons stability
• Strutted forging design to enhance rigidity under high load
• Precision-machined ring grooves for excellent sealing
• 21 mm wrist pin for durability and stability
• Performance-ready for naturally aspirated and tuned builds
• Comes with premium ring set (8450XX)

Specifications

• Bore: 84.50 mm
• Compression Height: 30.00 mm
• Wrist Pin Diameter: 21 mm
• Piston Material: 2618 Forged Aluminum
• Piston Weight: ~302 g
• Compression Ratio: Various - 9.44:1 (B16A), ~10.0:1 (B18A1/B1), up to 10.7:1 (B18C GSR)
• Set Quantity: 4 Pistons

Included Components

• 4x forged pistons
• 4x 21 mm wrist pins
• 1x piston ring set (8450XX)
• Circlips / wrist-pin retainers

Product Description

The Wiseco K623M845 is a high-performance forged piston kit tailored for Honda B-series engines, including B16A, B18A/B1, and B20B/Z (with VTEC heads). Built from strong 2618 aluminum, these pistons are designed for serious builds - whether you're doing a high-RPM naturally aspirated motor or a tuned race setup.

This kit features a flat-top crown and comes in several compression variants: for example, 9.44:1 for B16A, ~10.0:1 for B18A1/B1, and up to 10.7:1 for B18C GSR applications. The strutted forging design boosts strength, while ArmorGlide® coating reduces friction and improves longevity. Precision machining ensures great sealing, and the included 8450XX ring set provides reliable performance under load.

Whether you're building a street engine, race motor, or VTEC-powered B-series, the K623M845 offers a strong foundation. Proper assembly - including checking ring gaps, measuring clearances, and following torque specs - ensures you'll get maximum performance and durability from your build.