BOV noises

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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keithmoilanen
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BOV noises

Post by keithmoilanen »

Dont know where to put this or if it really has to do with the blow off vaulve but i was watching some old rally racing and they make some really cool sounds when down shifting and slowing down, or speeding up like a bunch of purges or something. i was wondering what it was and how to get that sound out of my t-leg.
well i guess the t-leg did not really make those sounds but i hear a lot of rally cars that do it.



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mike-tracy
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Re: BOV noises

Post by mike-tracy »

Something like this?



If you want your car to sound like that you'll need an aftermarket BPV/BOV.
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

Exactly like that thanks so what is a good one I should look for. Was it the Synchronic SB001 BOV? It sounds amazing I am confused on what exactly I need to buy.

So it's the surge I want correct?
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Thesubielover
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Re: BOV noises

Post by Thesubielover »

My blitz bov doesnt seem to want to make any noise. Ive adjusted it at idle under the hood and gave it gas by the throttle body, but no surge sound. I either have to take it to get looked at, or i need a new bov. I tried to loosen it back where the valve would just barely let air out at idle, but nothing. Any tips would be great.
93ss 3inch tbe, Hallman mbc,06 wrx td04, tmic, bov, bugeye seatsStolen x2, sold
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

I read it could be bad for the car
Next how to get my engine to sound like that
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Thesubielover
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Re: BOV noises

Post by Thesubielover »

It shouldnt be bad for the car. The only things that the bov does send the excess pressure to the air and the bpv shoots it back into the intake system. Different bov's make a number of sounds. Someone chime in and correct me if im wrong.
93ss 3inch tbe, Hallman mbc,06 wrx td04, tmic, bov, bugeye seatsStolen x2, sold
93ss Stroker,440cc inj, VF39, '06 TMIC, EJ20G heads & intake, EJ25 crank, 4.11Traded
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kimokalihi
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Re: BOV noises

Post by kimokalihi »

It's probably not really bad for the engine but it's letting out metered air from the intake which causes it to run a little rich when you shift or let off the throttle. I don't know if this affects the ECU over time as it learns but I've always wondered that. To me it's just a silly noise that gets old after a while and attracts the wrong kind of attention. It can sound cool but it's a little obnoxious.
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macipusy
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Re: BOV noises

Post by macipusy »

BOVs are crappy for perfomance....its all just noise. Why let the air you already had in the system back out. A BPV is the way to go...helps to keep the turbo spinning between shifts and and doesn't screw with your AFR's between shifts and when you roll off the throttle a bit.
I say if you like the noise go for it, but if you are still running ther MAF based air metering, then its a performance downgrade.

Also, its hard to make a BOV blow off by revving while parked....you need some load on it to build boost in the system to blow off and make noise.
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

I have a bov already dumping into atmosphere it's pretty load I just like noise of the surges .
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Re: BOV noises

Post by Thesubielover »

Mine doesn't really even make noise under boost. Maybe I just have to mes with the adjusting screw more.
93ss 3inch tbe, Hallman mbc,06 wrx td04, tmic, bov, bugeye seatsStolen x2, sold
93ss Stroker,440cc inj, VF39, '06 TMIC, EJ20G heads & intake, EJ25 crank, 4.11Traded
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kimokalihi
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Re: BOV noises

Post by kimokalihi »

Yeah robert it should definitely be making noise so you prob have to adjust it or something. I would run a bpv though if I was you.
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Thesubielover
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Re: BOV noises

Post by Thesubielover »

I can hook my stock one back up. I like the bov sounds, meh whatever.
93ss 3inch tbe, Hallman mbc,06 wrx td04, tmic, bov, bugeye seatsStolen x2, sold
93ss Stroker,440cc inj, VF39, '06 TMIC, EJ20G heads & intake, EJ25 crank, 4.11Traded
93ss 4eat, coils, stanced, wraped, flat black, stock show car
mike-tracy
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Re: BOV noises

Post by mike-tracy »

The guy I linked to initially has some interesting, informational videos about BOV's, etc. Here's another from his channel.



With my stock 91 SS BOV (that I determined was leaking since Idle was -10 on the boost gauge, and swapping in another brought it up to -18/19), it sounded like the above. With the new one (primary off a TT lol), it sounds like 0:50 onwards in the video.

While not as loud as his car by a long ways, putting in a "coffee cup" made me able to hear the compressor. It doesn't have the cool turbo flutter like with my old leaking, slow to open and close BOV did, the turbo spools up slightly faster and I hit target psi now.
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Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

Any one know what they did to the engine in the second video I posted
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Legacy777
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Re: BOV noises

Post by Legacy777 »

keithmoilanen wrote:Any one know what they did to the engine in the second video I posted

What do you mean? Are you talking about a specific sound, or just in general what was done to the engine?
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

to the engine cause I want my engine purring like that
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kimokalihi
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Re: BOV noises

Post by kimokalihi »

Get a twin scroll turbo setup with a huge external wastegate, run a cone filter right off your turbo with a bov and straight pipe off the turbo 3"+.
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

Alright time to look into some new stuff
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Apex3
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Re: BOV noises

Post by Apex3 »

Mine is pretty damn loud with the stock bpv. Desnorkus, coffee cup mod, and intake will all make it much louder, and will cost less than a BOV

It's a rally car though, it won't sound exactly like that without some serious work. Part of what you're hearing is the turbo itself, ours are tiny and low boost so they don't make a whole lot of noise, though again, with the mods above mine makes a lot of noise, no whistle to it though.
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Re: BOV noises

Post by kimokalihi »

I think I heard yours. Were you at wcss last year? Someone with a whinestone ss had a really loud bov. I remember that. Sounded ridiculously loud for how slow it was going.
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Re: BOV noises

Post by mike-tracy »

Florin's BOV was vented to atmosphere and it was pretty loud. IIRC he was getting around 16mpg though.
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keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

i have intake 3 1/2 exhuast bov...
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kimokalihi
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Re: BOV noises

Post by kimokalihi »

Get an external wastegate and cone filter.
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"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson
keithmoilanen
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Re: BOV noises

Post by keithmoilanen »

I have a summit racing cone filter on right now
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Rubasu
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Re: BOV noises

Post by Rubasu »

I have a turboxs RFL type-h BOV and i love it. it blows off at 115db's. i dont have any problems.



But after this video i want that other one.
Last edited by Rubasu on Sat Jun 30, 2012 6:14 am, edited 1 time in total.
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