ICON Piston and Ring Kit, Hypereutectic, Flat, 4.000 in. Bore, GM, Kit (PART #UNI-KB6171KTM.STD)

KB Performance Hyper piston and ring kits are offered for a wide range of applications from street and towing to marine and race. The kits feature pistons cast from 390 hypereutectic alloy heat-treated to T-6 standards to make them stronger. The pistons also feature fully machined crowns and valve pockets. KB hypereutectic pistons come in several head designs, as well as standard and oversized bore sizes. All KB Hyper pistons are lightweight to improve throttle response and rpm changes, while still being strong enough to withstand high compression and high temperatures. KB Performance Hyper kits (KT) are completed with piston ring sets containing top rings of moly-coated cast iron (M) or ductile iron (D).