One pair of Bare 12 Degree Inline LS7 12D 3.3" MCSA Port BE cylinder heads CNC ported and valve jobbed with CHE valve guides and CHE Ductile Iron valve seats. Standard height exhaust port fits all existing headers.
Developed by Greg Good using the LS7 2.9" Intake port as a building block, the cross section was increased to 3.3" to create a mid sized port for appropriate applications. They flow 420+CFM, with 300+CFM at just .400" lift with a 2.250" valve. The heads share the same optimized valve locations as our record setting LS 12D Oval Port BA Cylinder Heads with 2.250" Intake valves and 1.600" Exhaust Valve flowing over 280 CFM.
Standard valve stem size is 5/16" with valve lengths of 5.8" . A 1.600" diameter valve spring pad can accommodate a 2.1" installed height
They feature a Power Adder friendly 60cc chamber. Available with CHE Ductile Iron Valve Seats or CHE Bronze Valve Seats.
Heads require aftermarket shaft mount rockers available from either Crower (Cast Stainless P/N 74435F - Billet Steel P/N 74435B) or T&D Machine (Billet Steel P/N 2482) and will likely require aftermarket pistons, or modification to existing pistons. Aftermarket Pistons are available from Diamond, Ross and others.
The LS7 3.3" version have the best atomization possible for a port of this size
They are a perfect match for our 4.5 and 5.0 BA LS intakes allowing complete customization for your intended HP requirements."