I agree that care needs to be taken with baffle placement, which is why functioning oil air separators need to be properly designed. Volume, baffles and flow. The idea is to slow the air down enough to allow the oil and water vapours to condense and separate from the air. An empty tank will not slow the air enough to allow this to happen. Obviously the air flow should not be slowed so much as to become a restriction, hence why volume is important. Trying to achieve flow and high vapour separation in a tank under 2L in volume is always going to be difficult. 



Not offended hence the smiley face in my reply. As I see it when you post on a public forum you have to accept comments both good and bad
This particular tank is going on a Formula Student car being built by a university I have been helping. So no street use and only short run times. The tank is required as part of the regulations, all cars must have a catch tank capable of holding a minimum of 0.92L.

Warren

Carbon Copies Ltd