GM LS FT Piston Set 4.070 Bore -4.1cc

The GM LS FT Piston Set 4.070 Bore -4.1cc from RACE TEC PISTONS is a forged piston set engineered for high-performance LS-series engine builds. This eight-piece set addresses serious engine builders and performance enthusiasts who demand precision-machined components for forced-induction, naturally aspirated, and competition applications. The flat-top design and -4.1cc dish geometry provide tuners with critical compression ratio control and detonation margin management in turbocharged and supercharged GM LS platforms.

Constructed from forged aluminum alloy, these pistons deliver superior strength and thermal stability compared to cast alternatives. The 4.070-inch bore specification fits current-generation LS blocks and popular overbore applications, while the 1.5 x 1.5 x 3.0 mm ring groove design accommodates modern piston ring profiles for optimal sealing and blow-by control. The -4.1cc (minus 4.1 cubic centimeter) dome creates a negative compression volume, allowing tuners to run lower static compression ratios without sacrificing combustion chamber efficiency—a critical advantage in boosted applications where knock resistance is non-negotiable.

This piston set is ideal for LS1, LS2, LS3, LS7, and LSA engine platforms, and suits builders pursuing 10.5:1 to 12:1 compression ratios with forced induction or aggressive camshaft profiles. Installation requires precision honing to 4.070-inch specifications and proper ring installation practices. The 11.4 lb set weight reflects the density and durability of forged construction. Choose this set when OEM or budget-grade pistons cannot meet your boost targets, longevity requirements, or competition specifications.