CNC Ported LS3 L92 Aluminum Cylinder Heads

The Lingenfelter CNC Ported LS3 L92 Cylinder Heads are a pair of aluminum performance cylinder heads designed to significantly enhance horsepower and torque. Lingenfelter's proprietary CNC porting procedure precisely machines the ports and chambers, duplicating the flow characteristics of their meticulously hand-ported master heads. This computer-controlled process ensures exceptional consistency and tight tolerances, offering superior performance results at a reduced cost compared to traditional hand-porting. These cylinder heads are based on the L92/LS3 aluminum head and were utilized on 2008 6.2L Chevrolet Corvettes and various 2007-2008 GM trucks equipped with L92, L76 6.2L, and 6.0L engines. The CNC machining process increases intake runner volume to 275cc (from a stock GM 261cc) and exhaust runner volume to 93cc (from a stock GM 89cc). Each head receives a precision 3-angle valve job for maximum flow and longevity, chamber size verification for correct compression, deck surfacing for flatness, deburring, pressure testing, professional assembly, and spring height setting. The base package includes porting of supplied cylinder heads and features stock 2.165-inch intake valves and 1.59-inch exhaust valves, along with stock retainers, locks, and valve seals. The pricing includes checking valve guides for proper size, with a replacement cost of $9.50 per guide if needed. Flow numbers are measured on a 4.125-inch bore, with peak flow rates reaching 358 cfm on the intake and 237 cfm on the exhaust at .650" and .700" lift respectively. Optional upgrades include LS3 hollow stem intake valves, Inconel exhaust valves, and Lingenfelter's L230075897 double spring kit with titanium retainers.