Youraagh!

Sorry to play devils advocate, but here's what I've learned from playing with bov's: If you want a dump/flutter switch run an electronic solenoid valve that connects the bov line to before the throttle and after it. Now you have a cabin switch that will give you either sututu or woosh... Also add in the turbotech anti wastegate creep valve, set to open the bov line to atmosphere at your boost pressure. Now your bov is also a safety overboost valve, enjoy