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 and PCV valve itself. The built-in baffle improves crankcase ventilation and decreases the quantity of oil and contaminants that make it into your intake. The built-in, no-maintenance restrictor eliminates the need for a PCV valve.
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.
GM Part # 12568002 - LS6 engine valley cover
GM Part # 12558178 - LS6 engine valley cover gasket