alxdgr8

Having an open cone filter will defenitely make it audible. I put a Bailey DV in my S4 and didn't notice much of a change until I got rid of the airbox now it's super loud....as loud as my turbo escort that had a HKS BOV.
Even with a stock Bosch diverter it's pretty audible on a 951 with AFM and cone filter...I could hear mine. I will be replacing it this winter though with a recirculated Greddy Type-S

Darwantae951

When I switched to a MAF, the DV and turbo sounds increased dramatically. I'll be using a Synapse BOV when I install my Tec system, but I can't stand the chirping sound of most BOVs so I bought one that wasn't very loud.

manticore33

I know, I know, it is your car. But, but, why? This thread reminds me of the DSM forums (and first-timers with turbo cars) posting "I want my car to go PPPPFTTTT." Neglecting the fact it meant dumping metered air and risking reduced performance, fuel economy, stalling (problem gets worse with more boost) too.

Removing your airbox and using a less restrictive air filter should give you all the audio you need. I could distinctly hear my 1g BOV through my cone type filter with it sill being recirculated -- AND I did not lose metered air.

Yes, I am an opinionated old grouch. But, hey while you are in there, you should get some whistle tips:

http://www.youtube.com/watch?v=0x_PyLw_xp8

And make your car go WOO, WOO!





Edit: (Super cranky today) -- Is it just me, but when I hear some kid running around popping their DV/BOV in whatever Subbie, Mitsu, or Dodge, I just wonder what they are trying to prove? Seriously, the primary attention it grabs is negative (immature) or encourages other punks to try to 'show you up'. Basically, the only attention you receive is from the male variety.

CPR

I wonder why Porsche set theirs as far away from the throttle then?

PixxByTango

My first guess is packaging. Then I also have to wonder which car we are talking about. Reference to where the air meter is and its sensitivity if it has one. There are a few reasons I could speculate but every racecar that I ever built with one and every Import has them close to the throttle body for the reasons I mentioned above. Even my 1000rwhp 427cid 1994 Ford Lightning has a Bypass mounted just before the throttle body.

In this pic you can see the Wastegate and the Bypass Valve.


As you can see it bypasses mid-pipe between the airmeter and the turbo. This was designed so that the rush of air neither affected the air metering or the spinning of the compressor wheel.


This is what 1000+hp sounds like doing a burnout at the shop.
http://www.facebook.com/v/1115885499323

Here is what that looks like giving a 600hp plus 250hp Nitrous Z06 a three car headstart!


Here is the same Supra back a year ago with the 6-speed tranny. Also note, this car is DRIVEN DAILY in Atlanta and gets 24mpg on the roadtrips!

http://www.facebook.com/v/1115885499323

ritzblitz

I enjoy the sound of an open wastegate more than a bov.

The noise of a bov is one thing that made the fast and the furious so popular....

Not to mention this is the first thing that comes up on youtube when you type "bov" http://www.youtube.com/watch?v=J9CKLSjBzL8

Techno Duck

The bypass valve is right up on the throttle plate on the 951.

Reimu

The 951 world needs more dose pipes

Go 'down undah' around here

Darwantae951

I was thinking the same thing. It's what? 4-5 inches down from the TB?

User 52121

I wouldn't do it unless you want ever ricer under the sun crawling over you whenever you're in traffic.

I installed a cold-air intake and cone filter on my '03 GTI 1.8T, and the stock bypass valve became audible. Not obnoxious, but you could definitely hear it. I didn't mind the sound... but EVERY punk *** in a Civic, WRX, or Evo took my car's BPV as some sort of mating call or war cry or something, because EVERYBODY in a sporty compact car thought I was trying to race them.

I took the CAI off 2 days after putting it on, I couldn't handle it. Drove me nuts.

951_RS

Hah I remember my gti after I put the intake and baileys dv also sounded quite loud afterwords. All sorts of people tried to race me. I wouldn't mind being able to hear the turbo on my 951, but I don't want it to be ridiculously loud either.
I think a maf set up would give just enough noise for me.

2bridges

noisy chirping bovs are total ricer. Absolutely no performance benefit, just goofy *** noise.

Can't stand that crap, and you will definitely be embraced by the ricer crowd, they love that ****

drift a 944

Well, contrary to what everyone seems to say, my car makes almost NO noise when shifting, only sometimes I can hear a very very feint "psh" sound if I listen very carefully. I can hear the turbo itself spinning (even at idle) because of having an open exhaust, but no blow-off sounds from WOT to off-throttle.

And again, I am using this setup:
EVO Motorsports DV
drop-in cone K&N filter (to replace airbox)
stock AFM
stock K26/6 turbo
Lindsey dual-port WG
3" downpipe and no cat or muffler.

Again, no sounds (at least not over the loud exhaust note) however I'm placing my bets that I will hear it much better once my MAF kit is installed to replace the AFM.

My goal is NOT to get an outrageous in-your-face blow me billy fluttering type of sound to gain attention, just a short, quick, single whistle that I can hear that will make me happy. The ricers are already licking my nuts because of the green wheels and straight exhaust and stuff, but I don't really care about them and I'd like to have the noise for my own personal satisfication (cool I just made a new word). I think installing the MAF will do just that for me, but out of curiosity...

Exactly the answer I was looking for regarding harm done. Thank you.

My next question out of curiosity, is this...
Approximately what time frame are you suggesting it would take before the turbo would fail? My plan for mid 2010 is to upgrade my stock K26/6 turbo to something larger and stronger. My stock turbo was rebuilt I think 5 or 6 years ago and has been used as a daily driver car ever since. Spins super smooth by hand and zero play. I read what you wrote several times to make sure I understand it all correctly.. But would it be safe to run a bearing type turbo and a BOV on the 951 and not have to worry about turbo failure? I understand that compressor surge will still be there and effect performance, but would it still be harmful to the turbo?


Thank you guys, this is indeed my first turbo car, have only had it for a year now and still trying to learn exactly how all of its functions work. Much much different than playing with my n/a 944 for the past 5 or 6 years.

Techno Duck

A bypass valve or blowoff valve basically do the same thing which is prevent compressor surge. I think you misinterpreted the post, when you have no bypass or blow off valve (or too stiff a spring in one) is when you get compressor surge.

What you need to be concerned about is whether it dumps the air charge to atmosphere or recirculates it.

drift a 944

You're right, I did get a bit mixed up there. Makes sense now though, thank you!