Wiseco K591M865AP Forged 86.50 mm Pistons for 1989-2002 Nissan Skyline RB26DETT

Vehicle Fitment

• 1989-2002 Nissan Skyline (R32/R33/R34) - RB26DETT 2.6 L 24V Twin-Turbo

Features

• Forged from 2618 aerospace-grade aluminum for high strength
• ArmorGlide® skirt coating to reduce friction and resist seizure
• Strutted forging improves structural integrity under high load
• Fully machined crown with 14 cc dome for optimized combustion
• Anti-detonation groove to help prevent knock
• Forced-pin oiling ensures reliable wrist pin lubrication
• Includes performance ring set (8650XX) pre-gapped for tight seal
• Designed for heavy-duty, high-performance or racing applications

Specifications

• Bore Diameter: 86.50 mm (3.405 in)
• Stroke: ~73.68 mm (2.901 in)
• Compression Height: 30.00 mm (1.181 in)
• Dome Volume: +14.00 cc
• Compression Ratio: ~8.18:1 (or ~8.25:1 depending on block/deck)
• Wrist Pin Diameter: 21.00 mm (0.827 in)
• Piston Material: 2618 forged aluminum
• Average Piston Weight: ~348 g
• Deck Clearance: ~0.15 mm (0.006 in)

Included Components

• 6x Forged Pistons
• 6x Wrist Pins (21 mm)
• Ring Set: 6x (1 mm / 1.2 mm / 2.8 mm) - Wiseco 8650XX
• Piston Locks / Circlips

Product Description

The Wiseco K591M865AP is a high-performance forged piston kit built specifically for the Nissan RB26DETT engine used in Skyline R32-R34 models. These pistons are made from 2618 aerospace-grade aluminum for exceptional strength, yet still maintain a balanced weight (~348 g) for high-RPM reliability. The +14 cc dome design supports a low compression ratio (~8.2:1), making these pistons ideal for turbocharged applications or highly boosted builds.

The pistons feature Wiseco's ArmorGlide skirt coating to reduce friction and prevent seizure under extreme conditions. Their strutted forging adds stiffness and durability, and the anti-detonation groove helps manage combustion stability. Forced-pin oiling ensures the wrist pins remain well-lubricated even under load, which is critical in a high-power turbo motor.

This kit also includes pre-gapped Wiseco 8650XX rings, which are designed for high performance and good sealing. Whether you're building a street-driven RB26 or a full race motor, these pistons deliver reliable strength and durability for demanding applications.