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 Specs
Intake 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