Starting in 2004 with the Gen IV LS engines, General Motors replaced the PCV valve with a 2.5mm fixed orifice. This move was, presumably, to save production costs and eliminate a serviceable part.
NOTE: A PCV valve serves a few purposes in the crankcase; promote negative pressure and prevent boost pressure. Also, in the event of a backfire, the PCV valve prevents combustible vapors from igniting in the crankcase.
The Radium Engineering PCV catch can kit improves the performance of the LSA crankcase ventilation system. The catch can runs inline between the PCV valve and the intake manifold. The included bracket replaces the OEM intercooler coolant filler bracket and mounts the catch can.
When the intake manifold pressure is close to or greater than atmospheric pressure, the PCV valve closes and this hose experiences no flow. The PCV hoses will experience metered vacuum when the engine is idling, steady state cruising, and decelerating. This would normally draw unwanted crankcase vapor, unspent fuel, and oil sludge into the intake manifold immediately after a high load run.
Because the OEM 2.5mm orifice port is restrictive, a replacement baffled oil cap is included to draw as much blowby from the crankcase as possible.
NOTES
- The PCV catch can kit is compatible and recommended to be used with the CCV catch can kit. See 20-0563-FL below
- No extra inline check valve is required since Radium catch cans are pressure sealed
