Catch Can with or without PCV?
#21
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I just did a tune up on my brothers 05 Tahoe with the 4.8 in it.. his pcv valve seemed like it was just the body, no check valve inside but a tiny hole about the size of a pencil led. How is this better than the ball check? I have a catch can but haven't installed it yet but If I were getting a quart every 1500 miles, I would dump that **** back into the motor.. that **** cost me $12 a quart..
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#22
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Ha I have a new catch can sitting on my bench.
It's there cause I have no friggin room in the engine compartment to install it.
Between having AC and living in CA, you can barely get your hand anywhere into the engine area.
I'd like to put that catch can right up the cans of the CA smog *****.
It's there cause I have no friggin room in the engine compartment to install it.
Between having AC and living in CA, you can barely get your hand anywhere into the engine area.
I'd like to put that catch can right up the cans of the CA smog *****.
#23
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Realizing that this is an old thread...
Why would we want it closed @ WOT when crank case pressure is greatest? It closes when crank/intake pressure are equal or when crank pressure is less than intake pressure; in immediate off throttle conditions. Smaller area on intake side of PCV valve allows for it to close when pressures are equal.
IMO, having some form of vacuum connected to the crank case is never a bad idea. Vents caustic air fumes & reduces the pressure that the pistons have to over come on the down stroke. This reduction is one reason why drag racers use vacuum pumps to increase HP.
Large cams that don't create enough vacuum are another reason that drag racers use vacuum pumps (added to avoid it being added by a reader, but, it's not important to the point).
#24
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This is always true with four cycle engines.
With V twin HD motors, we even use reed valves in the crankcase to evacuate any pressure.
At times we have even kept worn oil rings from blowing by just by generating a good negative pressure in the crankcase.
With V twin HD motors, we even use reed valves in the crankcase to evacuate any pressure.
At times we have even kept worn oil rings from blowing by just by generating a good negative pressure in the crankcase.