the mazdaspeed3/6 come with bpv's if all you want is the pressure release sound you could just buy an intake. its not as loud as a bov but it sounds good. if think your ****ty stock bpv is leaking, which it could be its plastic you could buy one of many, most of them need an adapter but a few dont. forge and turbo xs makes a bov and a bpv that you dont need an adapter.
http://mazda3online.web.aplus.net/in...?cPath=281_160 protege garage is a great place, they offer an HKS SSQ v2 bov that doesn't need and adapter. if you want the best of both worlds the turbosmart below is awesome.
http://www.streetunit.com/Turbosmart..._p/tsvalve.htm


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