Wiseco K643M955AP Forged Piston Kit Nissan VQ37VHR 95.5mm Bore 9.0:1 Compression -15.5cc Dish

The Wiseco K643M955AP is a Professional Series forged piston kit engineered for the Nissan VQ37VHR 3.7L 24-valve V6 engine. Built from 2618 aluminum alloy and forged in the USA, these pistons are purpose-built for serious performance builds demanding strength, durability, and precision.

The "AP" designation denotes Wiseco's exclusive Armor Plating coating applied to the piston crown and wrist pin bore. This abrasion-resistant treatment raises the hardness of the aluminum, increases ring groove durability, prevents micro-welding of piston rings, reduces carbon buildup, and combats corrosion from detonation events.

Each piston also features Wiseco's ArmorGlide skirt coating, which minimizes cylinder wall friction and scuffing during break-in while reducing noise and freeing up horsepower. The crown face is textured to improve combustion characteristics.

Key Specifications:

• Bore: 95.50 mm (3.760 in.) — Standard
• Compression Ratio: 9.0:1
• Dome Volume: -15.5cc (Reverse Dome / Dish)
• Compression Height: 1.198 in. (30.43 mm)
• Stroke: 3.385 in. (86 mm)
• Rod Length: 5.886 in. (149.5 mm)
• Wrist Pin Diameter: 22 mm (0.866 in.)
• Material: 2618 aluminum alloy forging
• Country of Origin: USA
• Coating: Armor Plating (crown) + ArmorGlide (skirt)

Kit Includes:

• Wrist pin set (S710 22mm x 2.500 in.)
• Ring set (9550XS)
• Wrist pin locks

Designed for turbocharged and high-performance naturally aspirated VQ37VHR builds, the K643M955AP provides a reliable, performance-oriented compression ratio suitable for forced induction applications. Wiseco's dedicated forgings ensure an optimal strength-to-weight ratio with specially designed valve pockets and an optimized skirt profile for multivalve engine architecture.