Wiseco K594M845AP Forged 84.50 mm Pistons for Honda B16 / B18 / B20

Vehicle Fitment

• Honda B16A (1.6L DOHC 16V)
• Honda B18A1 / B18B1 (with B16A VTEC head)
• Honda B18C (VTEC, high-compression head)
• Honda B20B (with VTEC-head conversion)

Features

• Forged from 2618 aerospace-grade aluminum for maximum strength
• ArmorGlide® skirt coating reduces friction and resists scuffing
• Strutted forging design for high-load durability
• Fully machined crown with 8.3 cc dome for high compression
• Anti-detonation groove to mitigate knock
• Forced-pin oiling for reliable wrist pin lubrication
• Pre-gapped high-performance ring set (8450XX) included
• Available in multiple CR (compression ratio) options depending on engine setup

Specifications

• Bore Diameter: 84.50 mm
• Compression Height: 30.00 mm
• Piston Volume (Dome): ~8.30 cc
• Compression Ratio Options: ~11.6:1 (B16A), ~12.4:1 (B18A1/B1), ~13.0:1 (B20-VTEC)
• Wrist Pin Diameter: 21.00 mm (0.827 in)
• Piston Material: Forged 2618 aluminum
• Piston Weight: ~279 g
• Ring Set: Wiseco 8450XX

Included Components

• 4x Forged Pistons
• 4x Wrist Pins (21 mm)
• 1x Pre-gapped Ring Set (8450XX: 1/16, 1.2 mm, 2.8 mm)
• 4x Piston Locks / Circlips

Product Description

The **Wiseco K594M845AP** is a high-performance, forged piston kit tailored for Honda B-series engines with high compression needs. Built from 2618 aluminum, these pistons deliver excellent strength and lightweight characteristics, making them ideal for race or high-RPM street builds.

With a bore of 84.50 mm and a compression height of 30.00 mm, these pistons feature an 8.3 cc dome, offering a range of compression ratios depending on your application - from ~11.6:1 for a B16A setup, up to ~13.0:1 for a B20 block with a VTEC head. The ArmorGlide-coated skirts help minimize friction and wear, while the strutted forging supports high load scenarios. Forced-pin oiling ensures proper lubrication to the 21 mm wrist pins under all circumstances.

Included in the kit is a pre-gapped 8450XX ring set, making installation more straightforward and reliable. Whether you're building a high-revving B16, a high-compression B18, or doing a VTEC head swap on a B20, the K594M845AP offers durability, performance, and precision in one premium package.