SBC FHR F/T Piston Set 4.030 Bore -6.4cc

The ICON Pistons SBC FHR F/T Piston Set 4.030 Bore -6.4cc is a forged small-block Chevy piston package designed for high-performance engine builds. This eight-piece set delivers the precision bore diameter and compression ratio tuning necessary for serious power development while maintaining structural integrity under extreme cylinder pressure.

The -6.4cc piston cavity reduces overall displacement while lowering compression characteristics—a critical specification for nitrous oxide applications, supercharged builds, or pump-gas engines requiring detonation control. The ring groove configuration (1.5mm × 1.5mm × 3.0mm) is optimized for sealing performance across a range of boost levels and fuel octanes. Forged construction provides the durability demanded in street/strip dual-purpose platforms where repeated heat cycles and sustained boost pressure are routine conditions. The 4.030-inch bore diameter is standard for conventional small-block Chevy crate engines and stock long-block platforms, making this set compatible with existing block bores without requiring machine work.

This piston set serves engine builders, performance shops, and enthusiasts developing naturally aspirated, supercharged, or turbocharged small-block Chevy platforms where compression ratio and bore sizing are core tuning variables. Buyers should verify piston pin diameter, rod length compatibility, and block deck height with engine specifications before ordering. Proper installation requires precision hand-fitting and careful attention to ring end-gap clearances per ICON's technical guidelines.

Small-block Chevy piston selection is driven by displacement goals, compression targets, and forced-induction strategy. The -6.4cc cavity on this ICON set makes it a popular choice for turbo and supercharger builds where keeping compression ratios in the 9.0:1 to 10.5:1 range is necessary for reliability on pump fuel.