yes m8 porsche use varible vain on there turbos now, as for most of the vag group, and the ones that do use a waste gate the ecu controlled electric and do not flutter as they open a little or a lot to keep boost set not open close open close like a actuator so u wont get that flutter noise and is exposed to hold a steady boost but there not perfect yet, but still do there job i suppose as well as the old fashoned type, so back to the point, why would they waste money fitting a bov, yes u can run any turbo without it i have myself, if they thought it did nothing with there billions of pounds in researching why use 1.
