Yes once it passes the the air filter it is classed as an engine gas. This is from my understanding of QLD rules. Due to;Air from BOV or Air Bypass Valve contains a small percentage of highly pressurized recirculatory gases from breather pcv & turbo charger which are fed back into the intake & may contain unburnt engine gases,oils, vapours, etc and therefor Atmo's are in contradiction with Vehicle Emisions Standards & the EPA Act. Rules state to state differ. Eg, Pod filter is legal in QLD as long as it is attached to the car body. Pod filter in NSW is legal if it is in its own box. VIC rules suck - http://epanote2.epa.vic.gov.au/EPA/publications.nsf/2f1c2625731746aa4a256ce90001cbb5/c90ec843f3bbbe8fca256d9f00181c59/$FILE/1031.pdf There is no 2 intake mod rule in QLD and oiled filters are allowed