My brother might buy me a blow off valve for christmas. "I believe it is called P.I.T a Nopi brand, but it worked well and wasn't to awful loud. Forsale Blow valve for wrx/STI, Direct replacement has flange." that is what my brother said. I don't know much about BOVs but I'm not wondering if this is good or not, I am wondering if there will be a differnece with my car since my car comes with a re-circulatory valve (...right?). Is it bad to get a BOV (other than the rice effect...)? Will there be any preformance change? :dunno
Most of the info I've heard has been negative. Your definetely not adding power, you actually might lose power... I've heard claims of them making your car idle ruff... basically they are just noise unless you have major mods done.... I will say if your going to get one, make sure its a known brand and make sure its 50/50 atomospheric/recirc...maybe someone will correct that... My suggestion is to skip it...I know its a cheap mod and it sounds cool but the general verdict is bad. I say you take that money and get a cold air intake. Install that and remove your stock airbox and snorkus...It sounds like a BOV without the negative effects.... but then youre gonna get me started on +/- 's of intakes and brands/types to purchase...
i got the GFB Stealth BOV which is either full res. or atmoshic there are no gains with it. the only thing good with it is the sound plus after i put it on when im onthe intersate and its fully atmosphic i have the lovely afterfire and nice little fire balls come put of my exhaust. but IMP take the money and save it for an AP or up/down pipe or I/C hoses. get something that youll notice.
I actually have the PIT on my car Matt and its a woosh sounding bov that is the same design as the GFB and soudns the same. Its not that loud you just hear a rush of air eveyrtime. I only put it on there bc i got it for free. I used to have the HKS. you will gain no performance i have heard people say the turbo spools faster blah blah blah...i disagree. If you want the sound then yes go for it, plus your bro is buying it for ya. Or you could get something else from him. basically its up to you.
Bigb, is it similar to my cold air intake with the silencer removed? It makes a nice woosh sound, but it's not that loud. The only way I'll get a bov would be that it's loud, and knowing that changing from re-circulatory to blow off won't really do anything bad to my car.
our cars do not react well to fully atmospheric BOV's. you may find a bad idle, lower than normal boost pressures, stalling, black rear bumper (if you're catless). if you're going to get one like said before, get a well known brand that is a 50/50 or adjustable one