Synchronic BOV Subaru WRX (Video) 2 discussions This is a different version of the Subaru video comparing the Tial 50mm BOV with the Synapse Synchronic SB001 BOV. Test vehicle is a Subaru WRX with Garrett GT30R, external wastegate and running 20 p.. Tags: boost bov blow-off valve turbo diverter dv hks greddy tial subaru wrx sti gt