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JFP in PA · 06-03-2016, 01:50 PM

Problem is that the AOS system draws vacuum on both cam covers and thereby the sump. Even at only 5 inches of water, hot oil is going to give off some level of oil vapor, as well as other vapors (we will get back to that in a moment). To limit the vapor transmission to the intake hose (read vacuum source), the catch can device needs to be cooled to condense this vapor back to a liquid. This presents a couple of issues: Where to put the two devices (one of each bank, otherwise you would need one larger unit), how to cool them and keep them cool in proximity to a hot engine, and how to get the condensed vapor separated (some of it is oil, some is water, some is fuel) so that only the oil portion is returned to the sump. You would also need to figure out how to dispose of the non oil components from the cans as well because you do not want them returning to the oil system. (currently, they are sucked as vapor into the intake and burned).

Add in conditions where there is an overly large amount of liquid oil being thrown about the inside of the cam covers (high RPM and g loads in the corners at the track), and now you have some liquid oil entering the catch can system as well. This also has to be handled at the separation stage.

None of this is insurmountable, but it would take some very intricate engineering (read expensive) to make it all work.

06-03-2016, 01:50 PM	#9
JFP in PA Registered User Join Date: Feb 2005 Location: It's a kind of magic..... Posts: 6,273	Problem is that the AOS system draws vacuum on both cam covers and thereby the sump. Even at only 5 inches of water, hot oil is going to give off some level of oil vapor, as well as other vapors (we will get back to that in a moment). To limit the vapor transmission to the intake hose (read vacuum source), the catch can device needs to be cooled to condense this vapor back to a liquid. This presents a couple of issues: Where to put the two devices (one of each bank, otherwise you would need one larger unit), how to cool them and keep them cool in proximity to a hot engine, and how to get the condensed vapor separated (some of it is oil, some is water, some is fuel) so that only the oil portion is returned to the sump. You would also need to figure out how to dispose of the non oil components from the cans as well because you do not want them returning to the oil system. (currently, they are sucked as vapor into the intake and burned). Add in conditions where there is an overly large amount of liquid oil being thrown about the inside of the cam covers (high RPM and g loads in the corners at the track), and now you have some liquid oil entering the catch can system as well. This also has to be handled at the separation stage. None of this is insurmountable, but it would take some very intricate engineering (read expensive) to make it all work. __________________ “Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein Last edited by JFP in PA; 06-03-2016 at 01:54 PM.