never realized how much info doesn't get out. i'm going to comment on many of the responses to this post, without quoting anyone specifically. unless you're running a non-mass set up (such as a vpc) then you should recirculate the air back into your intake. not only does this keep the car from stalling between/after shifts, it also helps keep the turbo spooled as the air is pointed in the trajectory of the compressor wheel (but the correct direction...as opposed to with no bov the air would slam back into the compressor wheel every time the throttle closed, but in the opposite direction...shockwave). if you decide to purchase an aftermarket bov soley for the "noise" (that's gay) and feel you must have it "blow off", then be prepared to stall at stop lights and stop signs...and it will suck. however, if you're cool with that, then you must plug the "leak" you've now created in the intake after the MAS (where the recirculation tube connects), otherwise you'll run rich all the time as a result of the metered air being lost (you don't plug it to "keep the engine from getting dirty" as someone said. although, if you left it open, sh*t "could" fall in the hole and destroy the compressor wheel, but probably wouldn't get much further than the intercooler...and there would be some unfiltered air entering the engine, but that's not the point). however, if you purchase it because the stock (stock 1g) bov can't handle much over 17psi before it begins to leak pressure, then that's great...but if you understand that then you also understand the need to recirculate, so this post would be uneccessary. finally, i've yet to here an aftermarket bov that wasn't far louder recirculated than a 1g BOV vented open air...so, again, recirculate...it'll still be louder, if that's what you're after, and you won't have to worry about stalling at lights and stop signs.