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At the moment I am running my catch can with pcv so rockers tee into the catch can then other port goes from catch to intake but I want to go atmo now instead. What happens if you run same setup as I have now except replacing the line from can that goes back into intake with just a breather? From what I read most choose to delete the pcv when going atmo does it make a difference if you keep it?

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because you have to if you're running an AFM, if you're running a MAP sensor go for gold also the reason for deleting the PCV is to reduce foreign air and other shit entering your motor without passing through the air filter.

Remember the PCV will "suck" air during idle

Block it and avoid the engine sucking in oil vapour is the main reason.

If your "breather" on the atmo can is a mini filter, the air in the cam covers is "filtered" but full of all sorts of vapours that most people don't want in their engine for performance reasons.

The PCV only opens under vacuum, so it has no adverse effects on the engine if it inhales oily air at idle. If it did, the engineers would have found another way to achieve the result, which is to reduce emissions of engine gasses to the atmosphere.

Oil in the intake stream is only a problem under load, because oil is a serious octane reducer.

To the OP, if it ain't broke, don't fiddle with it.

The PCV only opens under vacuum, so it has no adverse effects on the engine if it inhales oily air at idle. If it did, the engineers would have found another way to achieve the result, which is to reduce emissions of engine gasses to the atmosphere.

 

Oil in the intake stream is only a problem under load, because oil is a serious octane reducer.

 

To the OP, if it ain't broke, don't fiddle with it.

i see your engine doesn't enter vacuum on gear shifts... Or need high octane fuel the moment the throttle is jumped back on after a gear shift...

Ive ended up blocking and going atmo, my main reason for doing this is as a test as I cant figure out why my intake and cooler is getting oil in it as turbo seals were checked are 100 percent fine and breather lines and catch can are empty so with this I can eliminate another option as to where the oil is coming from.

Ive ended up blocking and going atmo, my main reason for doing this is as a test as I cant figure out why my intake and cooler is getting oil in it as turbo seals were checked are 100 percent fine and breather lines and catch can are empty so with this I can eliminate another option as to where the oil is coming from.

did you have any sort of mesh or baffling in your catchcan?...a pipe in. pipe out catch can with no internal baffling will do nothing and oil will just end up in your intake again....get a stocking and fill it with coarse steel wool , put it in your catchcan and make the inlet hose go to the bottom of the can while the breather hose exits the top...so that way the vapous re filtering through the mesh on the way up and this will cath most of the vapours..and your can should fill with oil instead of your intake

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