QCS CNC Ported GM 823 Heads LS3 L92

CNC ported GM 823 Rectangle Port Castings Competition 5 Angle Valve Job 2.165" Intake & 1.59" Exhaust Valves 275cc intake runner, 93cc exhaust 66.1cc chambers Completely Assembled with our QCS Dual 660 Valve Springs w/ Titanium Retainers Laser Engraved QCS logo Sold in Pairs  CNC L92 LS3 Flow SpecsIntake valve lift / Exhaust valve lift.200 - 158 cfm / .200 - 116 cfm.300 - 230 cfm / .300 - 161 cfm.400 - 282 cfm / .400 - 201 cfm.450 - 302 cfm / .450 - 213 cfm.500 - 322 cfm / .500 - 220 cfm.550 - 340 cfm / .550 - 226 cfm.600 - 350 cfm / .600 - 231 cfm.650 - 358 cfm / .650 - 234 cfm.700 - 344 cfm / .700 - 237 cfm