[mtn05sleeper]

Originally Posted by mtn05sleeper

Thanks nandanrp. I'll Try to put it in the right place next time. mtn05sleeper

Go Aps

did he do a 100% atmospheric BOV conversion, or did he do his homework and go 50/50?

APS warranties this piece as the only solution to stock+ tuning with a recirc BOV. If I want to boost up, I can and I will not change the TMIC BOV. Cheers

[stamps]

someone correct me if I am wrong. The way a bov/bpv works is this (this is where I may be wrong) when the throtlebody closes there is a pressur build up that is released by the bov/bpv, I am assuming each has a certain pressure at which the valve opens and then closes later, as to not stall the compressor. however the air that is re-plumbed is put back to the turbo inletpipe pre-turbo, which means that no matter what you will run rich in theory because the imediate air is less than calculated by the maf, my thought is that with a bpv, following the rich senario you will run lean because of the air that was previously accounted for now being present, that and the computer noticing the rich state and accounting for it. Just my thoughts/logic on the subject. If I am flawed in any way someone please let me know, I have yet to see definitive right up on the subject.

in the end it really doesn't take very long to shift right?


EDIT: I spell at a 3rd grade level, please leave those comments alone or we could be here all day

[Majin]

Originally Posted by stamps

someone correct me if I am wrong. The way a bov/bpv works is this (this is where I may be wrong) when the throtlebody closes there is a pressur build up that is released by the bov/bpv, I am assuming each has a certain pressure at which the valve opens and then closes later, as to not stall the compressor. however the air that is re-plumbed is put back to the turbo inletpipe pre-turbo, which means that no matter what you will run rich in theory because the imediate air is less than calculated by the maf, my thought is that with a bpv, following the rich senario you will run lean because of the air that was previously accounted for now being present, that and the computer noticing the rich state and accounting for it. Just my thoughts/logic on the subject. If I am flawed in any way someone please let me know, I have yet to see definitive right up on the subject.

in the end it really doesn't take very long to shift right?


EDIT: I spell at a 3rd grade level, please leave those comments alone or we could be here all day

answered nicely early in this thread by Scott Siegel:

Originally Posted by Subaru of Gwinnett

Does this help?

http://www.siegelracing.com/bov.htm

SS

[stamps]

Originally Posted by stamps

however the air that is re-plumbed is put back to the turbo inletpipe pre-turbo, which means that no matter what you will run rich in theory because the imediate air is less than calculated by the maf, my thought is that with a bpv, following the rich senario you will run lean because of the air that was previously accounted for now being present, that and the computer noticing the rich state and accounting for it.

This is my problem with the previous answer as read above. But again, this is all theory based on the dynamics of the system. I'd be interested if anyone has actualy had any real life issues of the car leaning out or shooting fireballs out their tail pipe. I got the same backfireing sound from my stock bpv as I do now with my bov full atmostphere and full recirc.

[STi8]

Originally Posted by stamps

someone correct me if I am wrong. The way a bov/bpv works is this (this is where I may be wrong) when the throtlebody closes there is a pressur build up that is released by the bov/bpv, I am assuming each has a certain pressure at which the valve opens and then closes later, as to not stall the compressor. however the air that is re-plumbed is put back to the turbo inletpipe pre-turbo, which means that no matter what you will run rich in theory because the imediate air is less than calculated by the maf, my thought is that with a bpv, following the rich senario you will run lean because of the air that was previously accounted for now being present, that and the computer noticing the rich state and accounting for it. Just my thoughts/logic on the subject. If I am flawed in any way someone please let me know, I have yet to see definitive right up on the subject.

in the end it really doesn't take very long to shift right?


EDIT: I spell at a 3rd grade level, please leave those comments alone or we could be here all day

I understand where you're getting at, I was thinking about the exact same thing as you.

I think I figured it out by doing this, someone correct me if I'am wrong.

I was imagining the air as the shape of a cube. 100 Cubes of air lining up entering the intake, passed MAF to turbo to ic to intake manifold and to the engine at 10 psi.
When the TB closes, cubes of air get recirculated with the bpv back to the line up again maintaining 100 cubes of air.

With a BOV, let's imagine the tb closes and it blows off 10 cubes of the air, but the MAF measured 100! The next time the TB is open, 10 cubes of air will be missing from the line up, so only 90 cubes of air will be going into the engine therefore the engine might run rich for a second or two. Then after, the intake takes back 10 cubes of air again to make it 100 again maintaning good A/F ratio until the next time you let go of your gas pedal..

[anthongy817]

So a highend BPV will work the best?

Forge BPV FTW!?

[BluSTiKy]

I love stirring the pot on these sort of things. So just read what I have to say and consider it for what it's worth.

I agree that BPV allows for the cleanest operating of the fuel metering system I have no arguments about that.

But....

If you use a BOV and the metered air is dispersed to the netherregions of your engine bay this creates a very rich state. This excess fuel is dumped into you hot headers and ignites. While nowhere near as controlled this sounds oddly like what anti-lag does. This excess fuel can then spin the turbo faster between shifts as it ignites.

I don't think that the theoretical benefits of this uncontrolled BOV anti-lag out weight the benefits of a properly functioning fuel system but its food for thought none the less.

PS. I'm running Forge BPV

[Zach STI]

I just found this artcile while searching around on google, its extremely helpful to those who dont know the difference between a BPV and BOV.

http://www.streetracersonline.com/ar.../turbo/bov.php

[KOSTI]

I know this is old and like beating the dog to death.

I thought I would share my BOV thoughts.

I did research and a lot of it. I thought to myself, what the hell let me try it and see what I personally think. So here it goes..

1. HKS SSQV BOV was my choice.
2. It was a lot of money for nothing more than a nice, cool, some what annoying sound.

3. The Install and what I found.

3a. This BOV is great in the field of quality. It was made nicely and you can tell the BOV did not have cheap engineering written all over it.
<o></o>
3b. The install was simple, after all it was a direct bolt on and took minutes to install. The only hard part; that damn C Clip, however with the proper tool it was in place within a min. Everything lined up correctly and was simply nice and safe. Came with all the proper parts and even clamps to clamp down Vacuum lines.
<o></o>
4. How was it?
<o></o>
4a. First; I drove off got in to boost ASAP, after all I wanted to hear the sounds and test everything. Voom Psssst and Car went dead. LOL! Yeah pretty freaky; ended up being the C Clip which was not seated correctly and came loose. I fixed the C Clip and made sure it was planted correctly. After all, it was my first time working with the Clip and pliers which clamp it into place.
<o></o>
4b. Clip is in place and no issues while I drove around, loved the sound.
<o></o>
4c. Idle time: Well, to be honest I was expecting the worse after reading peoples posts from several forums. When the car died from the C Clip not being seated correctly; I figured that was what everyone was talking about. The IDLE was a bit bumpy, really nothing I would consider annoying but still nothing like the stock BPV.
<o></o>
4d. Drove around for a week with the HKS SSQV installed. It was nice and I did enjoy the sound, but still, the car did not seem to enjoy the idle. Like I stated, it was bumpy but we are talking minimal. However, there was a clear misfiring feel to the car. Never threw CEL or anything to that nature, but something was not happy.
<o></o>
4e. In between shifts I did not notice anything or any loss, gain, or anything but the noise.
<o></o>
5. Took it off, drove around for a day and instantly noticed the difference. Sure minus the sounds and all, the car seems a lot smoother and idle is nice and not bumpy.

6. Conclusion, my HKS SSQV is going up for sell. Sure I paid a good amount for it but to me sometime you have to try for yourself and learn. In ending this write up, I will say the difference is noticeable and the car enjoys full recirculation. The HKS SSQV is a great BOV, but the way the car is idling under its command; well it’s just not happy.
<o></o>
7. Lesson Learned: It was fun, minimal issues on my behalf. However, stick to the stock BPV. The car runs better and seems to be happier. I should mention that I did not loose boost or experience any effect while in boost.
<o></o>
8. Try it yourself if you would like. Like I stated; sometime you have to experience things on your own and there is nothing wrong with that!
<o></o>

[BigRigger]

I got mine free from the stealership, had it on since day 1. Now have 24xxx km on it and no noticeable problems.

[osbjmg]

Sounds like a good time, almost as good as bubb rubb's whistle tip, only more expensive.

[KOSTI]

I forgot to mention. I did notice the "Pop Pop Bang Bang" out the muffler, it was not loud but it was happening.

BTW BigRigger, I hear what you are saying. Like I stated, I tried it and it was a bit rough, noting too crazy, but for me I can tell the difference. I have read some people have had no issues to little. From what I felt, I can see how it's not a huge ordeal, i just personally feel the car likes the BPV vs BOV.

Good luck with it

[stealthsti06]

Originally Posted by KOSTI

I forgot to mention. I did notice the "Pop Pop Bang Bang" out the muffler, it was not loud but it was happening.

BTW BigRigger, I hear what you are saying. Like I stated, I tried it and it was a bit rough, noting too crazy, but for me I can tell the difference. I have read some people have had no issues to little. From what I felt, I can see how it's not a huge ordeal, i just personally feel the car likes the BPV vs BOV.

Good luck with it

that "pop pop bang bang" and or back fire was a result of that bov running your car to rich IMO

[stealthsti06]

KOSTI switching back to stock bpv is a great idea and that write up on that hks bov was great!

[howboutthemapplz]

everyone is talking about one extreme or the other, as far as recirc or atmosphere. what does everyone think about a 50/50? now that we understand that the full atmosphere is no good... has anyone had any experience with a 50/50??? any opinions on the 50/50??