Wiseco K634M865 Forged Piston Kit for Honda K24 / K20 (86.50 mm, +5 cc)

Vehicle Fitment

• Honda K-series engines - K24 block with K20A/Z head

Features

• Forged 2618 aluminum construction for superior strength
• ArmorGlide® low-friction skirt coating to reduce wear
• +5 cc dome design for higher compression tuning (~12.5:1)
• Sport-compact series optimized for high-RPM performance
• Precision ring grooves and anti-detonation groove for sealing
• Forced pin-oiling for reliable lubrication under load
• Includes performance ring set (8650XX)
• 22 mm wrist pins for strong pin strength

Specifications

• Bore: 86.50 mm
• Compression Height: 30.00 mm
• Piston Crown Volume: +5.00 cc
• Compression Ratio: ~11.0:1
• Wrist Pin Diameter: 22 mm
• Piston Material: Forged 2618 aluminum
• Piston Set Quantity: 4
• Typical Piston Weight: ~311 g
• Ring Set: 8650XX included

Included Components

• 4x forged pistons
• 4x 22 mm wrist pins
• 1x ring set (8650XX)
• Circlips / wrist-pin retainers

Product Description

The Wiseco K634M865 is a performance-focused forged piston kit designed for Honda's K-series engines, particularly for a build using a K24 block with a K20 head. The +5 cc dome gives you a higher compression ratio (~11.0:1), ideal for serious tuning and high-RPM performance.

Constructed from strong 2618 aluminum, these pistons are built to withstand high stress. The ArmorGlide® coating minimizes friction, while the forced pin-oiling ensures the 22 mm wrist pins stay well-lubricated under aggressive loads. Precise ring grooves and a high-quality ring set (8650XX) help maintain excellent sealing and durability.

This kit is ideal for race or tuned street motors where compression and strength matter. Proper installation - checking ring gap, verifying clearances, and torquing to spec - is essential for long-term performance and reliability.