This is a discussion on "The BIG BOV thread" (Where all bov question threads get merged) within the Engine Modifications forums, part of the Tech & Modifying & General Repairs category; Originally Posted by eastsideSTI wut what...
06 STU STI
2006 STU Pro Solo Natl. Champ.
The ricer in me finally took over and I bought the gfb stealth BOV for my 06 STi. It suppost to be one of the better ones on the market and it sound great. It helps me shift better because the revs drop a lot faster.
Now for the negatives...
My car is more jerky when I let off the throttle under boost and I get compression surge at low boost and low RPM's. So basically its killing my turbo.
I would suggest just getting a SPT intake and call it a day.
Snale Power: -BriTon
RSTi Swap FTW
Hawk-Eye Allience #013
lol reading > me
Bugeye Mafia #158
don't get a BOV. it is just that simple. nuf said.
proud owner of a 2004 Subaru WRX STI, silver on silver (pics should be taken when i get home on dec 8)
Toyota Celica GT-S (my baby who got run over by a drunk driver)
get the pink one.
Blobeye Syndicate #2004
Military Militia #30-06
2004 WRX - JBP:Stage 2:13.93 @ 96
Wingless alas. Too bad it took a 50 ton truck to make it happen.
Well, after learning what I have about these cars I have decided that I really need to get the stock bpv back on the car. Does anybody have their stocker for an 02 that they are willing to part with? If not, does anybody know where I can pick one up without breaking the bank at the dealer?
04 WRX Java Black
Mustang Dyno 218 awhp 216 awtq
1978 Honda CB400Tll
yea you know its modified
1974 Honda CB750 Bobber
still in the works
Vag-eye Militia #1
Military Militia #3
I died and went to heaven!!!!!
2008 Satin White Pearl WRX Sedan w/ Navi
2005 San Remo Red WRX Sedan w/ VF34 (traded)
Pi Kappa Alpha | New England Flat 4
HKS SSQV is probably the best one to get. I have been running mine for 20K miles and haven't had a single problem. check my mods in my profile.
BUGEYE MAFIA #20
So I have seen it time and time again on the Forum when someone says "what BOV do I get" and everyone yells that they shouldnt do it. I have also seen when someone that has a BOV goes and says, you guys are pansies and ends up getting butt raped prison style by everyone. What I have to say is based on experience, and also by fact because I just tested it:
You guys can yell and scream about it after, but I am going to make a comparison, about 100% recirculation Bypass Valve, and 100% atmosphere Blow Off Valve. Dual stage ones that can go 50/50 I will not comment on because there is such a variation of how they work, and they are more of a compromise in sound and design. So let me write it as a script.
BOV: Fact is, with a direct vent to atmosphere it will release pressure faster becuase there is no restriction. Yes of course you do create an audible sound.
BPV: I cannot vent pressure as fast as a BOV because I have to send air back to intake tube, but there is a reason I do it. When I open, I create a loop around the inlet and outlet of the turbo, so when shifting, the air can freewheel through in a circle and let me run in neutral. Its not much, but the MAF sensor doesnt sense any more air ingestion, and doesnt compensate and run rich for a second and make the car jerk.
BOV: But wait dude, I make a PSSSSSHHHH!!!!
BPV: I know you are all about that bling bling, but I was designed for a reason. Oh and here is something I bet you didnt know. When you step on the gas at idle or at no/low boost I actually open, and let air flow through me backwards!!!! Now not to say anything nasty about me, Yes I do take it both ways.
AFblueSV1k: See folks I actually did a quick test, in my garage with my STOCK BPV and a Mighty Vac brake bleeder. Putting anything more than 10 in.Hg on the vacum line, overrides the spring pressure, so valve is sitting neutral, not open nor closed, and can be pushed. So that means if the past of least resistance is in the intake through the bypass line, into the intercooler, and into the manifold. So at times the your car will run naturally aspirated and bypass the turbo completely untill the turbo picks up and can take over at 0 psi, because WOT in a Naturally aspirated car is 0psi/0in.Hg. At these times, the turbo is actually a resistance in the induction system, so it was designed to be bypassed and increase no/low boost throttle response. This would explain how some get compressor surge and reduce throttle response with BOV.
Final verdict: The BPV is better for a reason, sorry it doesnt make the Pssshhhhhh!!!!!! for some of you, but it does actually run better on the car. So now go and complain to the Subaru engineers that designed the WRX that aftermarket BOVs dont work on your car and they shouldnt have spent so much time desgining the best car that they could for you.
Last edited by afbluesv1k; 11-30-2006 at 12:36 PM.