The LS6 engine valley cover is an excellent upgrade over the factory LS1 PCV system. This cover eliminates the two rear valve cover PCV hose connections as well as the PCV hose. The built-in baffle improves crankcase ventilation and decreases the quantity of oil and contaminants that make it into your intake.
Direct bolt-on for 2001-2002 LS1 engines. Earlier LS1 engines require some minor cutting of a boss in the engine valley that interferes with the cover baffle. Also required for the conversion is a valve cover plug (part #12568011), a 5/16" vacuum cap and about 10 inches of 5/16" ID rubber fuel line. A how to guide for the conversion is available here.
Please note this valley cover does still require a PCV valve.
GM Part # 12568002 - LS6 engine valley cover
GM Part # 12558178 - LS6 engine valley cover gasket
2001-2003 Chevrolet Corvette
GM Gen III LS-series engines
A how to guide for the conversion is available here (please ignore the portion of the instructions regarding re-using the factory PCV valve - this 2004 valley cover has a built-in PCV restrictor and does not require a PCV valve).