Wiseco K542M8125AP Forged Piston Kit 81.25mm Bore Flat Top Honda B-Series

The Wiseco K542M8125AP is a professional-grade forged piston kit designed for Honda B-series engines. This complete 4-piston set features a flat top design with -2.4cc volume and an 81.25mm (3.199 inch) bore diameter, making it an excellent choice for performance builds and engine rebuilds.

Key Specifications:

• Bore Size: 81.25mm (3.199 inches)
• Compression Height: 29.85mm (1.175 inches)
• Piston Pin Diameter: 21mm
• Piston Weight: 281 grams each
• Flat Top Design: -2.4cc volume
• Compression Ratio: 9.8:1 (varies by application)

Advanced Features:

• Forged from high-grade 2618 aluminum alloy for superior strength and heat resistance
• ArmorGlide skirt coating reduces friction and minimizes scuffing during break-in
• Armor Plating on top face and ring grooves increases durability and prevents micro-welding
• Textured piston crown improves combustion characteristics
• Precision-machined ring grooves for optimal sealing
• Made from dedicated forgings for lightweight construction with optimal strength

Complete Kit Includes:

• Piston rings (replacement part number: 8125XX)
• Wrist pins (replacement part number: S656)
• Pin locks

Wiseco pistons are manufactured in-house using advanced forging and finishing processes, ensuring consistent quality and performance. The ArmorGlide coating material reduces friction and noise while freeing up horsepower. The Armor Plating technology raises the hardness of the aluminum, increases ring groove durability, reduces carbon buildup, and combats corrosion from detonation. This piston kit is ideal for high-performance street applications, engine rebuilds, and custom engine builds requiring precise bore specifications.