I have read all back posts on the bov and adding one. I saw the setup on jeorge's ste.. is the lower pipe where every one is putting them.. I read somewhere that it is best placed with in 14in of the throttle body? Just wondering, cause I just got my 1g bov and am going to being getting welded this week.. so any info on the best location would be greats..
Thanks..KCP
I couldn't tell you the proper place to put the BOV, but where the STE site has it is where I put mine. I do not hear the shock wave anymore and that is what you want to accomplish anyway... 8)
It can be placed anywhere after the turbo and before the throttle body.
Thanks for the info guys. I thought i t could go anywhere in between.. Just wanted to double check.. thanks again... KCP
(http://www.geocities.com/motorcity/track/8015/engine.jpg)
pictures are fundamental
Put it where the Red X is!!!! :lol:
geocities sucks I forgot!!!!
http://www.geocities.com/motorcity/track/8015/engine.jpg
The linky no worky...... :o
Quote from: 90tgpblkThe linky no worky...... :o
just take the engine.jpg off and get to the site...
i would say the lower IC pipe is a better place for the BOV than the upper pipe. first, the pressure would be relieved before having to traverse the intercooler. 2nd, there is a pressure drop across the intercooler, so there would be more pressure in the lower hose. the more pressure surge you can relieve means less stress on the turbo and you wouldn't have as much lag either. a BOV would be louder in the lower hose because of this. another small reason the lower IC pipe might be better for the BOV is that you would have more room on the upper pipe to place alcohol injection and an anti lag valve. my brother is using what the turbo dodge guys call an 'anti-lag' valve...it is a rubber flapper valve on the upper IC pipe that is open when the engine has vacuum, but closes as soon as it sees boost. the idea is to take a 'gulp' of fresh air before the turbo builds boost, rather than pull air thru the intake/intercooler/piping. anyone here using an 'anti-lag valve' on thier TGP? it's funny, on my brothers Shelby he has 3 K&N filters....a cone before the turbo, one small one on the BOV, and another small one on the end of the anti lag valve.
joshua
Wouldn't having the BOV in the lower make make the pressure go though the IC before it gets to the BOV. Since the pressure is coming back from the motor I would think the upper pipe would be better. Get rid of the preesure as soon as it comes out. :?
yes get rid of the pressure as soon as it comes out. the pressure wouldn't be coming back *from* the motor, more like from the turbo *to* the motor. when the throttle plate slams shut when you let off the gas pedal, all that pressure wants to force the turbo to a halt because it has nowhere to go. so the turbo is quickly slowed down, which is hard on the turbo of course and creates more lag since the turbo has to spool up again. if you relieve it out of the BOV on the lower IC pipe, it would be relieved before going thru the intercooler.
joshua
Coming from the throttle body the IC is before the lower pipe. It's between the IC and turbo. Are we talking about the same thing.
i'm not sure...the pressure isn't coming from the motor, it's coming from the turbo -> to the motor. when the throttle plate shuts, the turbo is still spinning very quickly and making boost. the boost guage wouldn't read this tho, since the MAP is on the other side of the throttle plate in the plenum. all that pressurized air needs to go somewhere so it might as well be right after the turbo on the lower IC pipe, vented ASAP before it tries to cram it thru the intercooler and up to the closed TB. mounting the BOV on the lower IC pipe will also relieve more compressor surge than the top since the lower pipe is always under more pressure due to the pressure drop across the intercooler. that is why it is louder (and more effective) on the lower IC pipe. mounting the BOV on the upper pipe will still work fine, but IMO will be more effective on the lower pipe. can someone tell me if i'm way off? i guess it makes sense in my head....
joshua
one thing to add tho, the BOV is opened by the vacuum signal from the manifold (vacuum when throttle plate shuts); the pressure spike itself doesn't open it. so that way, the BOV is opened before there is much of a spike to even build up. EDIT: IOW, 1st the throttle plate shuts. 2nd, the manifold sees vacuum now, which the BOV also sees at this time (by way of vacuum line) and this causes the BOV to open. this happens very quickly, before the pressure spike itself starts to slow the turbo down (or at least before the pressure spike starts to slow it down very much). that being said, the BOV would be better suited to the lower IC pipe, where it can relieve that pressure at the source, before it can cram even more air into the IC and up to the closed TB. i would never own a turbocharged car without a blowoff valve! (*ecspecially* a turbo car with a manual transmission) sure they can be mounted anywhere between the turbo and TB and still work great, but if you are doing a custom installation you may as well put it on the lower IC pipe where it will be more effective.
joshua
killer info! ty!
I disagree slightly. The pressure wave is coming from the throttle plate, the pressure is of course coming form the turbo. There is already pressure in the pipe, and when the throttle slams shut, all the air slams into the throttle, and creates a pressure wave moving away from the throttle. So the wave travels back and hits the compressor wheel, trying to reverse the wheels' movement. When it hits the turbo it goes the other direction and back and forth a few times. (hens the chuggling sound when you let off the pedal) If it was just an increase in pressure causing the turbo to slow down, it would never turn backwards. I've seen turbo compressors start spinning in reverse when the throttle is slammed shut. It don't know for sure if there is an ideal location for the BOV, there probably is, but how much difference it would make is unknown. As long as it is relieving the pressure and stopping the pressure wave before it gets back to the turbo its doing its job.
I want to thank everyone for there replies.. I would tend to agree that it really doesn't matter where as long as there is one on the system.. I have been looking at as many turbo setups and you see them in both locations.. So thanks again guys.. KCP
Since we use a BOV I would have to agree with everyone that says it doesn't really matter as long as there is one.
On a car with a MAF or vane air system it has to be after the intercooler due to the fact that the air is recirculated to before the turbo....and not having this air intercooled would lead to superheated air, and increased air intake temperature
Hey,
Who has a links for a few suppliers for a good BOV. I used to have one on a procharger setup. It came with it I really didn't have to research a supplier. Anyone have any contact??
Quote from: redturbo90Wouldn't having the BOV in the lower make make the pressure go though the IC before it gets to the BOV. Since the pressure is coming back from the motor I would think the upper pipe would be better. Get rid of the preesure as soon as it comes out. :?
Ok ok, there isn't pressure going anywhere. Its a shockwave. Imagine a line of people steadily moving along at an amusment part. They are all packed tightly together because they all want to ride and they are going to stop letting new people in in 5 mins. So everyone is trying to cram past the turnstyle to get in line. The gate to get on the ride is still open. The gate to get on the ride then closes suddenly, and the person at the front of the line sudddenly stops. So the person next in line (2nd) runs into him. The 2nd person bounces back and hits the 3rd person who bounces back and hits the 4th person and so on til it gets to the last person in line. The last person in line falls back against the turnstyle and hits it and causes it to spin backwards.
Can you see the analogy? The people are AIR. The air is tightly packed into a space (piping) and moving steadliy. Suddenly its stops moving forward, but is still tightly packed. Because air is a fluid, the entire mass doesn't stop at once, the molecules bounce off of each other. The reaction from hitting the GATE (throttle plate) causes a wave going backwards, until the last person hits the turnstyle (Turbo) and spins it backwards.
Chris
Uh, oh, I thought that was a new reply. Well anyway you get to hear my analogy anyway. :)
Got my bov sat, came off a 91 Laser turbo $0 (free). I put mine between the TB intake pipe and the intercooler. The only parts needed were 1 1/4" ---->2" adaptors that went on both the ends of the bov and the 2" side went tot he TB intake pipe and the intercooler $7.42. I bought a T fitting from Lowes $1.19 which I tapped off the MAP sensor and I had some red matrix vaccume tube lying around that I hooked to the bov. Works great very loud swooosh when you punch it and let off :twisted: . Its scary to think how much damage was being done without one :cry: !
1trucavaliern did you have any problems finding some one to weld the flange on you pipe.. I have gone to three shops and all say they won't do it.. course in my $hit town means not much.. Just wondering... and how much did you pay for the welding.. unless you did your self.. KCP
no welding required :D it just runs inline with your TB and intercooler.
i used the bov and the pipe, its already attached.
Do you have a pic I would like to see exactly how you did that.. Cause if I can do it with out welding that would be sweet.. Thanks for the info..KCP
havent taken a pic yet, why i don't know but when i get home its pitch black outside. I don't have a digital so I would have to take a pic then take it walmart, get it developed/disc option and then upload the pic. I really need a digital. How about i just draw the schematic and e-mail it to you. I'll send it today to your email.
sounds good... i have to an eye out for it.. Thanks... KCP... :D
forget the schematic! I put the film in for hour service hopefully I will have it uploaded my this evening or saturday.
pics still are not ready WTF!!!!!!! still waiting on walmart!
walmart sucks...... :(
hehehe.....
Thanks in adavnce for the pics... KCP
Hell yeah! I am going to install one this coming weekend if I can get a BOV from the wrecking yard. I will post pics as soon as its done. Thanks for the great idea on how to do it.
hopefully this damn pic works (http://us.f1.yahoofs.com/users/4c3c795f/bc/Yahoo!+Photo+Album/IM000023a---1.jpg?pfuBh.9AYtKOVcO2)
X makes the spot!!!! :sleeping:
hey cav can you email those pics.. I can't get my pc to load the image on the forum.. Thanks KCP
90tgpblk! did you ever see the pic? i sent it to your e-mail
Did you ever get the pic to work? I'd like to see it too.
Thanks
Is anyone going to post the pics?
Thanks,
Thomas