Wiseco K634M875 Forged Piston Kit for Honda/Acura K-Series (87.5 mm Bore)

Vehicle Fitment

• Honda / Acura K-series engines - K24 block with K20A / K20Z head
• Examples: 2002-2006 Acura RSX Type-S, 2002-2006 Civic Si, 2004-2008 TSX

Features

• Forged 2618 aluminum for high strength and durability
• ArmorGlide® low-friction skirt coating reduces wear and noise
• +5 cc dome design for high compression tuning
• Strutted-forge construction for enhanced rigidity
• Precision-machined ring grooves and anti-detonation groove
• Forced pin-oiling for reliable lubrication under high RPM
• Includes a high-performance ring set (8750XX)
• 22 mm wrist pins for strong, durable connections

Specifications

• Bore: 87.50 mm
• Compression Height: 30.00 mm
• Dome Volume: +5.00 cc
• Compression Ratio: ~12.9:1 (depending on build)
• Wrist Pin Diameter: 22 mm
• Piston Material: Forged 2618 aluminum
• Piston Set Quantity: 4
• Typical Piston Weight: ~318 g

Included Components

• 4x forged pistons
• 4x 22 mm wrist pins
• 1x ring set (8750XX)
• Circlips / wrist-pin retainers

Product Description

The Wiseco K634M875 is a professional-series forged piston kit designed for Honda K-series builds, particularly those using a K24 block with a K20 head. The +5 cc dome design delivers a high compression ratio (~12.9:1), making it ideal for high-RPM naturally aspirated or race-oriented engines.

Constructed from durable 2618 aluminum, these pistons are built for extreme performance. The ArmorGlide® skirt coating reduces friction and wear, while the strutted-forge design enhances structural integrity. Forced pin-oiling ensures consistent lubrication for the 22 mm wrist pins even under severe conditions.

This kit includes a premium 8750XX ring set to help maintain sealing and performance. For best results, install with precision - check ring gaps, verify clearances, and use proper torque specifications to maximize reliability and horsepower.