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Old 08-25-2008, 04:44 PM   #176
wrxodee
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Thanks for this. So very helpfull
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Old 08-25-2008, 04:54 PM   #177
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Giving this thing a much needed to-the-top.
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Old 08-25-2008, 11:20 PM   #178
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Quote:
Originally Posted by Keiji22 View Post
Giving this thing a much needed to-the-top.
Why? Unabomber's manifesto is a fun-filled sticky full of informational links such as this. So stop post whoring.

Last edited by hdempsey; 08-25-2008 at 11:24 PM. Reason: post whoring not allowed.
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Old 09-01-2008, 12:06 PM   #179
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Frst I'd like to say that the faq and many of the posts have been extremely helpful. I am 21 years old however and love that BOV sound and would love to have it. I'd never do anything to my car that would be harmful though, a *slight* performance loss I wouldnt mind if it's something that makes the car more enjoyable since this is just my daily driver...my T/A is for the performance =).

So all that being said what I am still confused about is if "The downside of releasing the air to atmosphere is that it has already been metered by the mass air sensor, and when it blows off, the ECU will be injecting the wrong amount of fuel into the cylinders" that it seems obvious that relocating The MAF to after the air has been released into the atmosphere like others have suggested would give you a correct reading and solve the running rich problem...what seems obvious and what really is aren't always the same though. I've read that this does and I've also read that it doesnt solve the problem...leading to the confusion. If it does not solve the problem would anyone be able to explain why not?
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Old 09-02-2008, 12:06 AM   #180
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Quote:
Originally Posted by v8subie View Post
Why? Unabomber's manifesto is a fun-filled sticky full of informational links such as this. So stop post whoring.
My bad unibomber. Leave the thread alone please. Its here for information NOT post whoring.
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Old 09-03-2008, 11:19 PM   #181
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Originally Posted by Raslian View Post
An hour to install a BOV? Pfft, I can do the up-pipe in half that time.
I install my blow off valve in 11 min.
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Old 09-04-2008, 02:10 PM   #182
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Originally Posted by NJTunersMagazine View Post
Oh, but you still can't go with an aftermarket bov because that would cause you to run rich. Is my theory correct by the way?
Dude,you can buy upgraded valves that will fully recirculate.Jebus christ,check out some websites.
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Old 09-04-2008, 02:14 PM   #183
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Quote:
Originally Posted by quaker View Post
Frst I'd like to say that the faq and many of the posts have been extremely helpful. I am 21 years old however and love that BOV sound and would love to have it. I'd never do anything to my car that would be harmful though, a *slight* performance loss I wouldnt mind if it's something that makes the car more enjoyable since this is just my daily driver...my T/A is for the performance =).

So all that being said what I am still confused about is if "The downside of releasing the air to atmosphere is that it has already been metered by the mass air sensor, and when it blows off, the ECU will be injecting the wrong amount of fuel into the cylinders" that it seems obvious that relocating The MAF to after the air has been released into the atmosphere like others have suggested would give you a correct reading and solve the running rich problem...what seems obvious and what really is aren't always the same though. I've read that this does and I've also read that it doesnt solve the problem...leading to the confusion. If it does not solve the problem would anyone be able to explain why not?
Search "blow through (thru) MAF" or you can go speed density (MAP based fueling).These are not new concepts.This has been done for decades with other MAF based forced induction vehciles.This is not just a Subaru thing.The problem with the blow thru MAF is most people think you can just move the MAF without having to retune.Not so.Plus you have now moved the airmeter in to a highly pressurized area where it maybe not is designed to be and is exposed to more turbulance than being in front of the turbo.Too much work for a frigg'n kazoo.Also more benifits of using a BPV.
http://spdusa.com/blow-off_valves.htm

Last edited by quazimoto; 09-04-2008 at 02:23 PM.
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Old 09-04-2008, 07:44 PM   #184
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I'm not sure quite yet but i have reason to believe that i would rather see kids putting blow off valves on their cars than smoking CRACK!!!!!!!!!!!!!!!!!!!!

Leave the youth alone and stop picking on them.
LOL! Ricers FTW!!!!!
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Old 09-05-2008, 05:59 PM   #185
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Thanks for the reply dumdum. Probly wouldn't do this anyway...but I was just trying to figure out a better alternative for those (like myself lol) that like the sound.
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Old 10-08-2008, 10:36 AM   #186
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I am having a hard time understanding something here. With a true BOV, when the air is vented to atmosphere, the ECU has absolutely no way of knowing that the BOV had an blow-off event. There is no sensor on the BOV/BPV or on the return tube. The air that was metered and meant for the cylinders is sent into the atmosphere; the ECU does not monitor the BOV or BPV. Therefore when the throttle body is opened again and the air intake takes in air, it is metered air, and then that metered air goes into the cylinders. With a BPV, when a blow-off event happens air is sent back into the air intake and that air is no longer metered because the air is sent into post MAF sensor and hence the ECU does not know about that air in the system. The ECU thinks that the air which was blown off was actually sent into the cylinders because the ECU does not monitor the BOV/BPV. I don't see how the ECU knows that a blow-off event happened. I don't see how the recirculated air is metered because after the MAF sensor there are no other sensors which monitor airflow. I don't know if I've worded this properly but I don't see how metered air which is recirculated post MAF sensor remains metered air. The only air sensor in the system is the MAF sensor and it is taken out of the loop when a blow-off or recirculation event occurs. The only way that I see it is that once a recirc event happens and air is recriculated back into the air intake that the recirculated air displaces or prevents an equal ammount of air coming into the intake and hence the AFR remains correct.

I think if you just replace the BPV with a BOV all you should have to do is to plug the hole in the air intake to prevent unmetered air from entering into the system and causing a lean condition. That and perhaps to add a small ammount of tube or hose to the BPV to prevent air from entering into it with small blow off events and then allowing unmetered air into the system.

Last edited by Wobblygoblin; 10-08-2008 at 10:43 AM.
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Old 10-14-2008, 10:41 PM   #187
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Quote:
Originally Posted by Wobblygoblin View Post
I am having a hard time understanding something here. With a true BOV, when the air is vented to atmosphere, the ECU has absolutely no way of knowing that the BOV had an blow-off event. There is no sensor on the BOV/BPV or on the return tube. The air that was metered and meant for the cylinders is sent into the atmosphere; the ECU does not monitor the BOV or BPV. Therefore when the throttle body is opened again and the air intake takes in air, it is metered air, and then that metered air goes into the cylinders. With a BPV, when a blow-off event happens air is sent back into the air intake and that air is no longer metered because the air is sent into post MAF sensor and hence the ECU does not know about that air in the system. The ECU thinks that the air which was blown off was actually sent into the cylinders because the ECU does not monitor the BOV/BPV. I don't see how the ECU knows that a blow-off event happened. I don't see how the recirculated air is metered because after the MAF sensor there are no other sensors which monitor airflow. I don't know if I've worded this properly but I don't see how metered air which is recirculated post MAF sensor remains metered air. The only air sensor in the system is the MAF sensor and it is taken out of the loop when a blow-off or recirculation event occurs. The only way that I see it is that once a recirc event happens and air is recriculated back into the air intake that the recirculated air displaces or prevents an equal ammount of air coming into the intake and hence the AFR remains correct.

I think if you just replace the BPV with a BOV all you should have to do is to plug the hole in the air intake to prevent unmetered air from entering into the system and causing a lean condition. That and perhaps to add a small ammount of tube or hose to the BPV to prevent air from entering into it with small blow off events and then allowing unmetered air into the system.
Once air flows past the MAF sensor, it becomes "metered", meaning that the ECU has measured how much of it there is.

When the throttle closes, the BPV takes pressurized air from after the turbo but before the throttle body, and circulates it back into the intake tract after the MAF sensor. Since the space between the MAF and the engine is enclosed, and all the air that fills it has been metered, the ECU knows exactly how much air is there. Since the ECU knows exactly how much air is going into the engine, it can calculate how much fuel it needs to inject. A BPV moves metered air around in your intake tract, but since it recirculates after the MAF sensor, the total amount of air between the MAF sensor and the throttle remains constant.

As you said, the ECU *doesn't* know when a blowoff or recirc event has occured. With the BPV setup, this doesn't matter, because a recirculation has no effect on the total volume of air in your intake tract. However, this is an issue in a BOV setup. Instead of putting metered air back into the intake tract where it belongs, a BOV vents all the pressure into the atmosphere, removing air that the ECU expects to be there. Since the ECU has no idea when this occurs, it continues to inject fuel for all the air that flowed past the MAF sensor, even though some of it has been vented. This is what causes your car to run rich.

Admittedly, it's not *that* big a deal that your car runs rich for short intervals, but it certianly doesn't help anything. Plus, BPV's decrease spool time, since when they actuate it eliminates the load on the compressor wheel, which causes it to remain spinning.
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Old 10-22-2008, 09:04 PM   #188
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has anyone heard of a flow through system in which you can use a 100% atmospheric BOV without the bucking/ richness. Ive heard of it before but havent been able to find much info on it
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Old 12-06-2008, 06:22 PM   #189
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ps, I know a lot of new people to the wrx think its going to be a good mod, I completely understand this. That is why we should come right out and say, don't do it unless you want less power, slow building boost between shifts, and less drivability (in so many words). If you want to sacrifice all those things for a noise makers, than at least you were informed first...[/quote]



thanks...
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Old 01-21-2009, 04:01 PM   #190
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Quote:
Originally Posted by Unabomber View Post
Blow Off Valve FAQ

Term usage: "Blow off valves" go by several names, among them are compressor bypass valve (CBV), air by-pass valve, bypass valve (BPV), blow off valve (BOV), Diverter valve, and possibly a few others. BOV is the common and incorrect term that lumps true blow off valves and bypass valves under the same term. For the sake of correctness, this post will refer to either aftermarket BOV, aftermarket BPV or OEM BPV as these are the most correct terms.

What is the function of a blow off valve (BOV)? To release pressure from the intake tract of a turbo car when the throttle closes. It is a vacuum-actuated valve designed to releases the air to the atmosphere.

What is the function of a bypass valve (BPV)? To release pressure from the intake tract of a turbo car when the throttle closes. It is a vacuum-actuated valve designed to recirculate the air back into the intake before the turbo inlet, but after the airflow sensor.

What is the purpose of a BOV/BPV? When the throttle closes and the intake system is under pressure, the high-pressure air entering the motor will bump into the closed throttle plate, and in the absence of a BOV/BPV, a pressure wave will travel back to the turbocharger. The result is that the compressor wheel will stall (a phenomenon known as “compressor surge”) and slow down very quickly. This is hard on the bearings and decreases the turbo’s lifespan, but it also means the turbo will take longer to spin up the next time the throttle is opened.

Are aftermarket BOVs necessary with Subaru turbos? No. The OEM BPV is perfectly fine up to 20psi of boost. For applications using higher boost levels, an aftermarket BOV/BPV should be considered.

Can I mod my stock BPV to hold higher boost? Yes. This link gives detailed instructions on how to do so.

Is the STi BPV better than the WRX BPV? No. They are the same. However, the JDM STi BPV will hold more boost as it is physically different than both the USDM STi BPV and the WRX BPV. The specific PSI rating of the JDM STi BPV is unknown, but users have reported it is good up to 25 PSI.

Is an aftermarket BPV better than the stock BPV? No. Unless you are considering an aftermarket BPV solely for the purposes of holding higher boost levels. An aftermarket unit should sound just like the OEM unit.

Which manufacturer is best? This topic is highly debated. There have been no reported consistent "bad" aftermarket BOVs. Obviously, there may have been bad ones sold, but not enough to report as "bad" overall.

What are the different types of aftermarket BOVs/BPVs? Different manufacturers use different methods. There are three basic types:
1. Aftermarket BPV: Similar in function to the OEM BPV where 100% of the air is recirculated.
2. Atmospheric BOV: 100% of the air is vented to the atmosphere.
3. Hybrid BOV: These depend on the manufacturer and end user settings. These can either be adjustable or manufacturer set for different percentages of atmospheric/recirculation dumping. They can also be set to work as recirculation during lower boost conditions and 100% atmospheric during higher boost conditions.

Are there any downsides to aftermarket BOVs? There have not been significant amounts of problems with BOVs. Aftermarket BOVs can and do require some light end user maintenance to keep them performing perfectly. For aftermarket hybrid BOVs that have end user defined settings, there will be an initial period of adjustment to obtain the desired recirculation/atmospheric ratio. As well, most aftermarket BOVs will require "tuning" (usually via supplied washers, a screw, or other mechanism on the BOV itself) to allow them to idle correctly and blow off at the right time.

Are there any negative effects with aftermarket BOVs? Yes. The downside of releasing the air to atmosphere is that it has already been metered by the mass air sensor, and when it blows off, the ECU will be injecting the wrong amount of fuel into the cylinders. The engine temporarily runs rich, meaning too much fuel is injected into the cylinders. On most tunes the target A/F under boost is @11.1:1 or so. Say you are at 11.1:1, then you shift and it vents. It will swing rich, typically to around 9.5:1. That is not that rich and this period lasts for under one second...again, nothing to write home about.

This temporary rich condition isn’t usually that harmful. Technically, it can eventually foul spark plugs and even clog the catalytic converter as unburned fuel on the catalytic converter burns very hot, and too much of it can melt the cat. The odds of either of these two conditions actually happening is very, very low though, but that's the theory.

As to blanket "you'll run rich" statements, a BOV will only run "rich" during hard acceleration and shifting as 99% of the time it stays closed.

Can my tuner or engine management tune out this rich period? Yes. There are some forms of engine management that can tune this out. Buying your engine managment soley for this purpose is a poor method of choosing an engine managment system though.

What about a 50/50 or BOVs that you can portion the VTA portion? This is a bad analogy, but if a BOV is a person in a wheelchair, a 50/50 BOV is a person in leg braces. It's not as bad, but not good enough to say bolt it up. If you find a deal on one or happen to like the sound of a particular model, go for it, but don't think you are doing your car better vs. a 100% VTA model.

Won't I be labeled as a ricer? It's your car, do with it what you like, but be aware that many people are prejudiced against BOVs just like neon underbody lights and other accessories. Be aware that a BOV can be seen as a dinner bell for street racers though. It attracts attention both good and bad.

So a BOV is not bad then right? Not so fast...most BOVs leak. Even ones that are religiously maintained, installed, and are from quality manufacturers. A leak in essence means less boost and less power or your car will be working harder to produce boost than it means, which can decrease reliability.

How do I set up my BOV to not leak/stand less chance of leaking? Read the BOV manual/instructions first off. Learn how to adjust it. If it doesnt have a manual, just look at the valve. You can almost aways figure out how to adjust it. Some have screws, some use washers under the spring, others use replacement springs. Now that you know how to adjust it, here is what you do:

First off, start the car, get out and open the hood. If you can see the piston of the valve (look in the hole it vents out of if its a VTA valve), check to see if it is moving at all at idle, or worse, partially open. You want that piston rock solid, not moving at idle.
Now give it a little gas. It shouldnt move when you step on it, and when you lift, it should pull up a bit. Depending how hard you hit the gas, it will either JUST move, or fully open.
If its doing anything but what it should be, adjust it a little tighter.

Now go drive the car

When you shift at light throttle, is it venting? If so, is it a pure straight vent, or do you get a little bit of a "chufchchchc" noise right before it vents? That noise is compressor surge. Which isnt as bad as some people like to think and say. Ideally, you are looking to hear a little surge then a vent. Or no sound at all. Either is ok. Now drive it hard, does it surge a little or just straight vent?
Get out of the car and tighten the valve and drive it again. Repeat this until you get a LOT of surge when you lift under boost. Now start loosening it until you JUST start to hear no almost surge.
What the surge means is that it fought opening just a little bit. If you hear a LITTLE surge just as it begins to vent, that means that the valve is holding itself shut as tightly as it is capable of, without being so tight that it doesnt vent properly.

I have had XXXX brand valve for years, it has never leaked. How do you know? By looking at your boost gauge? Looking at the boost levels in your datalog? Neither of those prove that the valve isnt leaking. The advice above tells you how to set it and KNOW for 100% sure.

But compressor surge will kill my turbo! Unless its really bad, it really isnt going to kill it.

I have had XXXX brand valve for years, it has never leaked. How do you know? By looking at your boost gauge? Looking at the boost levels in your datalog? Neither of those prove that the valve isnt leaking.

Where do I buy aftermarket BOVs/BPVs? Every Subaru/Import performance store sells BOVs. For purchasing, support your local economy or the NASIOC Vendors.

How hard is it to install aftermarket BOVs/BPVs? Allow around 1 hour for install time. Professional installation, depending on your area, is around $75. This is one vehicle modification that is very simple and can be successfully accomplished by even the greenest shade tree mechanic.

How do I install BOVs/BPVs? Refer to the BOV/BPV manufacturer's instructions. For BOVs/BPVs without instructions, below is a link to one of the better known installation instructions:
scoobymods.com instructions (with photos)

If you are wanting to be 100% sure you arent losing any power from a BOV, and you are running under about 22PSI, you are best off sticking with a stock unit.

Editors Note

My thanks to Dan of Mach V Motorsports for writing an excellent BOV article that provided a lot of the information contained within this FAQ. He also provided additional information that was helpful in the formulation of this FAQ. Also thanks to my buddy Davenow for his excellent BOV post found HERE that contains additional information.

This post was created because I wasn't able to find a good blow off valve FAQ. I came up with the text based on LOTS of searching here. Upon reading this you should have an idea of whether a blow off valve best suits your needs or not. The manufacturer is up to you.

If you find an error in this FAQ, please PM me with factual details and I will update this post. Responses such as, "I have XXX's blow off valve and it's great!" or "XXX's blow off valve broke after 1 month" are not appreciated here, that is what the Car Parts Review Forum is for.

so its saying that if i put on some aftermarket bov it might lose some power of mine turbo huh

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Old 02-24-2009, 01:47 PM   #191
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Not to keep up the vicious cycle, but what are some examples of engine management that can tune for a BOV? Would Cobb's AccessPort be one, as that's what I plan on running? A BOV isn't that important, but I'll admit my inner ricer might force me to get one somewhere down the line.

Quote:
I'm not sure quite yet but i have reason to believe that i would rather see kids putting blow off valves on their cars than smoking CRACK!!!!!!!!!!!!!!!!!!!!
What if I wanna install a BOV while smoking crack? :P
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Old 02-24-2009, 01:54 PM   #192
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Originally Posted by SomeoneWhoIsntMe View Post
Every time the blow-off valve actuates, the ECU dumps excess fuel into your engine. While the effect this has on your overall mileage may be trivial, to say that it isn't a waste is foolish.
That fuel was going to get dumped into your motor anyway. The only reason its rich at that point because there is less air. Less air for same fuel creates a rich condition. Its a RATIO. Same air, more fuel, rich condition. Less air, same fuel, rich condition. Same air, less fuel, lean condition. More air, same fuel, lean condition. And so on and so on.
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Old 03-06-2009, 06:45 PM   #193
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Hi everyone,

Just thought we'd try and contribute a little more to this excellent debate as another thread has prompted our engineers to quote Dan's great summary.

Anyway, there's some comment and further tech about it here, http://www.suspensionparts.info/showthread.php?t=27413 . Its a bit long so we didnt feel comfortable about posting it here.

quaker, you might also find some other useful stuff specific to your original question here http://www.suspensionparts.info/showthread.php?t=27410 .

We'd love to keep the discusion going and look forward to your comments or feedback.

Best regards

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Old 04-23-2009, 03:28 PM   #194
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Originally Posted by urabus2 View Post
I've been doing a lot of research on rotated setups on the market. It looks like nearly all of them except the old-style Perrin with the rotated turbo silicone hose have NO provision to recirc the air from the BPV (making it effectively a BOV).

After speaking with them, P&L and Ultimate Racing both run their kits venting to atmo and Crawford, as was previously mentioned, runs their kits with no BPV/BOV whatsoever.

So, what the hell is the right way to do this? I can only assume that if I want my car to run right under all conditions I am going to have to customize almost any rotated kit to allow for recirc.
Bump for an old thread... it seems AMS is the only rotated kit with recirculating BPV option.

Which is nice. I want to go rotated but I don't need it to be loud.
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Old 07-16-2009, 12:00 AM   #195
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Suggestion:

Can you add a comment about consequence of leaky BPV / BOV?
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Old 08-07-2009, 09:37 AM   #196
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Thanks for all of the info in all of your posts. I am new to the subaru world and the knowledge I am getting from reading your posts are very very helpfull.
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Old 08-10-2009, 02:10 AM   #197
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I don't have an after market bov nor do I ever plan on using one but I do have a question-

Its my understanding that the factory bpv vents compressed air in to the uncompressed side of the intake (pre compressor) in theory wouldn't there be some loss of performance from adding hotter air in to the cooler intake track ( regardless of the intercooler my thought is that post turbo air will always be hotter than pre).
so in the perfect world I guess the set up would be an atmospheric valve with a fmic and the MAF about an equal distance from the intercooler to the intake manifold as the stock intake box to the maf. ( with proper tuning )

if any guru could comment on this it would be great
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Old 09-24-2009, 08:33 AM   #198
RA-AL
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"When you shift at light throttle, is it venting? If so, is it a pure straight vent, or do you get a little bit of a "chufchchchc" noise right before it vents? That noise is compressor surge."

Any chance of some advice from you? I have a 93 type RA, its running at 1.1bar @full boost and is fitted with the standard recirc/bov. I am getting VERY loud "chufchchchc" sound when i let off at around half throttle? Should i get an aftermarket BOV will this help??

Any advice would be very much appreciated
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Old 09-29-2009, 09:04 PM   #199
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Hi everyone, hopefully I can help with some technical answers here.

gopsu, when talking BPV leaks, it's very important to determine the size and cause of the leak to understand its affect on the engine. Leaks can be loosely grouped into two types:

Leaking gaskets, seals, piston-leak down, loose tolerances etc etc, and

The valve opening under boost.

Here is a link to an article that covers the first type in great detail:

http://racedotcom.com/showthread.php?t=27447

Generally speaking, the first type of leak is usually quite small, and although easy to detect, do not often affect the engine's performance since they represent a very small portion of the total amount of air being consumed.

The second type however is the one that does have great potential to affect engine performance, since even a small opening of the valve can drop a measurable amount of boost pressure.

Factory valves are generally designed to open above a certain boost pressure, and all MY01-on Subaru valves are of this type. The actual point at which they open depends on the model, but generally it varies from about 16psi to 20psi. That's not to say that you can't run more than 20psi with the factory valve - you can, but the valve will begin opening at this point. So you might reach say, 22psi with the factory valve, and 22psi is 22psi, right? Well, yes. However, what you will find is with the factory valve slightly open at this pressure, the turbo is being driven harder to reach this boost pressure. This means higher turbo shaft RPM, higher exhaust manifold pressure, and therefore less power for the same boost pressure than would be possible if the valve remained shut.

WaterWagon, good question. The temperature of the air that is dumped from a bypass valve depends on a lot of things, but most importantly, whether the valve is before or after the intercooler.

Universal gas laws tell us that air heats up when compressed. It also follows that air cools when de-compressed. In theory, in a perfect world if you compress air to say 15psi, then vent it back to atmospheric pressure, it would be exactly the same temperature that it began at. However, this is not a perfect world and there are losses to consider. A turbo is at best about 70% efficient at high boost, meaning that it adds more heat to the compressed air than compressing it alone, and gas isn't perfect anyway. If you vent the air immediately after the turbo, it will drop in temp, but you are correct, it will still be hotter than when it entered the turbo.

However, if that compressed hot air has passed through the intercooler, it remains at high pressure, but a great deal of the heat has been stripped from it. This means when you vent it to atmospheric pressure, it is possible for it to actually drop BELOW the turbo's inlet temp (depending on the eifficiency of the turbo and intercooler). Most factory turbo cars (including Subaru) have the valve mounted after the intercooler and so fall into this category.

However, this is all mostly splitting hairs for the following reasons: first of all, the valve (mostly) vents when the throttle is shut - therefore any air recirculated goes through the turbo, back out the valve, then back through the turbo, and not into the engine.

Secondly, the cooling (or heating, if the valve is mounted before the intercooler) effect of the air passing through the turbo would be minimal, since the valve takes less than a second to reduce the intercooler pressure to atmospheric. Even if the vented air were particularly hotter or colder than the intake air, the amount of it and the time it spends in the turbo is really quite negligible.

As for running the MAF after the IC and BPV, this is a relatively common mod, and many people report better drivability with it, but the benefits would not likely be a result of the temperature of vented air from the BPV.

RA-AL, the factory BPV on the MY93 is very small - the inlet and outlet are 3/4", but the acutal air path I.D. of the fittings is even smaller. Note that the turbo is more prone to flutter at low RPM, whilst spooling up, or when rolling off the throttle slowly - fortunately it is not generally detrimental under these conditions. However to get rid of the flutter, more air needs to be vented under these conditions.

Check your factory valve to make sure it's working - hook the vacuum line to the manifold of an idling engine (doesn't have to be the same car, you just need idle vacuum - I'm sure the missus won't mind using her car!!), and make sure the valve is open (blow through it). If not, the valve is probably stuffed and should be replaced.

If the valve is open, then you'll likely need both a larger valve, and also larger hoses and connections to it - fitting a larger valve to the factory hoses alone probably won't do it.

I hope this helps,

Best regards,
GFB Pete
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Old 10-06-2009, 10:08 PM   #200
downpipe12
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Quote:
Originally Posted by Petrus View Post
Bump, put it at the top dagnabbit! This is ridiculous!

this made me giggle like a schoolgirl.
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