HKS 21003-AN011 Billet Piston Kit Capacity Upgrade - VR38DETT 4.3L

The HKS 21003-AN011 is a precision-engineered billet piston kit designed for the Nissan VR38DETT engine as part of HKS's 4.3L capacity upgrade system. Featuring a 95.5mm bore diameter (φ95.5) with a 23mm wrist pin (φ23), these pistons are direct replacement components for the HKS 4.3L stroker build and are also sold as standalone repair parts for existing 4.3L kit owners.

Key Features:

• Billet construction — CNC-machined from high-strength billet material for superior durability under extreme performance demands
• Truss-design piston crown — HKS's special truss profile enhances structural rigidity while minimizing mass for an ultra-lightweight result
• Squish area geometry — Optimized combustion chamber squish area promotes high-rate, efficient combustion for maximum power output
• Stock bore diameter retained — φ95.5mm bore maintains factory engine block rigidity and ideal thermal conductivity without requiring block boring
• No full-flow modification required — Drop-in compatible with the HKS 4.3L capacity upgrade architecture
• Wrist pin diameter: φ23mm

This piston kit is a core component of the HKS VR38DETT 4.3L capacity conversion, which increases displacement from the stock 3.8L for a significant gain in torque and overall output. It is compatible with the HKS billet crankshaft (23006-AN007) and HKS H-Beam Step 3 connecting rods (23004-AN006). The associated piston ring set is sold separately under HKS part number 21005-AN015.