Blow Off Valve?

I need some help from the turbo KA owners, or those who have knowledge of turbo KA's. I have an XS kit sitting in my garage ready to be put in (very nice kit). I recently realized that the B.O.V needs to be recirculated like a stock turbo motor due to the S14's MAF sensor. Now, the good thing : recirculating air will spool the turbo quicker beween shifts, Bad thing : No PSHHH!!!!!!!!!!! Now, that sux because I love that wonderful sound between shifts. Here is what I heard. When the air goes to the atmosphere the computer doesn't know this and sends more fuel resulting in backfiring, funny idle, stalling out, etc. I know that with a VPC I can get rid of this, but it's too expensive. Here's the question: With a Super AFC, could I adjust the fuel so that when I let off the gas I don't have that problem. It would be a much cheaper solution. Thanks.

[West]

The AFC wont help. My HKS SSQV Vents to the atmosphere without problems. Although I have a Custom programmed Turbo ECU by JWT. I have never heard of this problem before. Only suggestion to you is get the ECU and deal without the nice BOV sound until you have the $ to get the ECU or VPC. I'd give it a try first though because I dont think it will stall on you or anything.

Thanks. Well, I plan on going with the better fuel setup in the near future. Jim Wolf ECU, 300zx tt injectors, fuel pump, Cobra MAFS. So if it gives me problems right now, I will just wait for the ECU in the future.

You can get an HKS VPC that can correct all the problems the afc cant. Recirculating the BOV does not mean you wont hear the PSSH noise, it will just be slightly quieter. Once you get even higher up in hp/boost, it makes a very apparent difference when you vent to the atmosphere or when you recirculate it. It does help the turbo to stay spooled ALOT. The only good thing that comes from venting to the atmosphere is the noise level, everything else is bad. The MAF couonts all the air that goes through it and expects that air to stay in a closed loop. When you vent, that air mysteriously dissapears and leaves the a/f ratio very lean. Too lean and you get the problems like stalling or backfiring like you said. The VPC or a standalone will allow you to set teh idle a/f unline the AFC which will allow you to adjust for the difference in the unmetered air, the only downfall is it will run you about 600-800$ when all you really have to do is dump the air back into the intake. <img src="#/f/iB_html/non-cgi/emoticons/sad.gif" border="0" valign="absmiddle" alt=':('>

[misnomer]

A little off topic. . .

I like your new avatar, Boost <img src="#/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'>

Yeah baby, shake that booty!

Yeah i like the avatar too!

Hey, can anybody tell me how the BOV is supposed to sound? &nbsp;I know there are some sound bites on the net, but I can't find it and I'm very curious....

[West]

Josh recorded some video/audio clips the other day of his car. Check out the Engine.mpg and some of the driving ones. You will hear the high pitched noise when he lets off the throttle at high rmp/boost. Most other BOV's sound different but you can still get the idea.

<a href="#/eclipse/movies.asp" target='_blank'>#/eclipse/movies.asp[/b]</a>

[96SEChick]

The car sounds awesome Josh! &nbsp;But, can you close your sunroof the next time you put the camera in there? hehe

[cheater240]

I think the mixture would go RICH after losing air to atmosphere. &nbsp;Computer thinks there is more air than there is, so it sends in more fuel. &nbsp;

Can't imagine why you would take all the expense and negative performance aspects of a non-circulating BOV just for the sound...

first time i heard that sound was on my friends eclipse.... but it wasn't supposed to happen..... i dont think the car is modded at all...... strange lol

[96SEChick]

My bf had a 92 Laser RSX (Eclipse wannabe)--turbo, all-wheel drive and the turbo sounded awesome! &nbsp;He'd get on it and all you'd hear is this woooooooooooosh! &nbsp;He hadn't modded anything except for taking the screen out of the MAFS. &nbsp;That's the only thing he wishes his WS6 had is that sound. &nbsp;He's planning to have that thing turbo'd in a few years though (seriously--he's getting prices and saving up for it right now).

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from cheater240 on 2:48 pm on July 31, 2001
I think the mixture would go RICH after losing air to atmosphere. Computer thinks there is more air than there is, so it sends in more fuel.

Can't imagine why you would take all the expense and negative performance aspects of a non-circulating BOV just for the sound...
</td></tr></table><span id='postcolor'>

True, I was being dumb and said it backwards, it will make you rich. And I completely agree with you on venting, to me it isnt worth it.

[transient]

I thought that the blow-off valve only vented the excess, wouldn't there still be a lot of air? If it doesn't vent, what's the purpose of a BOV??

boostaholic....

bad a$$!!!

I wish they had the eclipse here in Canada...i would buy that for my second car <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

[cheater240]

Transient--The BOV does vent the excess, but when you go from WOT to closed throttle and th eturbo is still spinning fast, the excess is a LOT. &nbsp;So it is important to address the fact that the MAF has already counted the air.

The main purpose of a BOV is to vent the excess air that would otherwise slow down/harm the compressor.

Boostaholic, You said that you agree with having the B.O.V recirculate the air. But in the videos it sounds like you have it atmosphered.

[mike]

Yo West, when do we get to hear your car? <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

[West]

Want to hear my car? Ok then... here is a shitty movie. Also, its running like shit so I didnt floor it all the way. Also, my 3rd shift I am in a underpass so your hear the BOV Echo. Movie is below... beware the 5MB file and the movie sux, but you can hear my car...

<a href="#/images/eclipse/movies/MOV00728.MPG" target='_blank'>#/images/eclipse/movies/MOV00728.MPG</a>

Boostaholic has everything he need to have it vent back into the intake. He just had to see what it sounded like for the time being <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

More movies are still to come.

Thanks West.

[transient]

ok, I get it. I love havin a place to learn all this stuff!

The movie don't werk...

[West]

DOH! Try now <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

I'm getting used to recognizing the BOV sound. I couldn't tell when you went under a bridge though...it wuz kinda dark....kinda reminded of blairwitch project <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

[West]

hehehe, were ya scared? JK. <img src="#/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>

I should have new movies during the daytime in a month or so once I fix some shit <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

To be honest...I've never been scared in a car b4...and i've been in some fast cars. &nbsp;

Your car is some bad a$$ [email protected]#$ though. &nbsp;At this point in my life I can only covet what you call your own. &nbsp;Do you mind me asking...how much have you spent on your car? &nbsp; And also did you do all the work yourself? &nbsp;

Oops...when you asked if i wuz scared...I thought you meant because of the power of your car...I forgot about my reference to the Blairwitch project :confused:

I think if i wuz in your car when you were filming i would;ve been like

:o

[West]

HEHE, No read my post about scaring people <img src="#/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

<a href="#/forum/topic.cgi?forum=1&topic=187" target='_blank'>#/forum/topic.cgi?forum=1&amp;topic=187</a>