get a bov if u want .. its ur car .. keep in mind the risks and hassles of having it thats all .. if ur car doesn't have central lockin which would surprise me, it doesn't cost much at all to put it in .. comes with most alarms .. make sure u get a good decent alarm though .. since i'm in adelaide, maybe u can lend me a ur copy of the workshop manual .. i'll make copies ... maybe u can just get a new air filter all together .. cost maybe about 200 or so for an apexi ..
good luck .. btw what colour is ur car?