they ran both bovs and higher boost and low the synapse doesnt surge at all plain in simple... hence why i wont sema best new product of the year turbo xs is known to leak so is gfb and practically every other bov out on the markey.. i still love the tial and hks but id rather have more efficeint products on my car and im running a blow thru so the bov doesnt make me run rich between shifts like it does with most of you