CNC PORTED LS3 L99 LSA LS9 CYLINDER HEADS
CNC ported GM LS3 aluminum cylinder heads can be used on 2008-2012 production 6.2L based Chevrolet Corvettes and various 2007-2012 L92 L76 6.2L and 6.0L based GM trucks.
LS3/LSA cylinder heads are precision CNC machined on a 5 axis CNC machine to ensure that tight tolerances are maintained. The CNC porting procedure is a computer controlled machining operation that duplicates details from a hand ported cylinder head. The port and chambers are carefully designed to provide the best combination of high flow capabilities across the entire valve lift range. Quality control procedures include sectioning sample cylinder heads to confirm minimum wall thicknesses.
Following porting each head receives: Precision 3 angle valve job to maximize flow & provide extended life, CC checking chamber size for correct compression, surfacing to insure deck flatness, deburring, pressure testing, professional assembly, setting spring height & checking all tolerances.
Intake volume - 275cc
Exhaust volume 93cc
Chamber Volume: 73 cc's
10.2:1 compression on a stock LS3 engine
9.33:1 on LPE low compression 417
9.2:1 on LPE low compression 427
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
All flow testing is done on a 4.125" bore