Two BOV's

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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CAV3MAN227
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Two BOV's

Post by CAV3MAN227 »

-Is it possible to run two blow off valves? Kind of a silly question in my eyes but with my current setup, this is possible, (refer to pic)

Image

-In the green circle, is for my recirc, for when I have to smog. In the red circle is my hard piped HKS bov. So could I safely run my my bpv and my HKS together simultaneously? If so, would there be any minimal benefit to a setup like this?

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog
alexandermf
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Re: Two BOV's

Post by alexandermf »

Is the hks half or full atmospheric

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CAV3MAN227
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Re: Two BOV's

Post by CAV3MAN227 »

^This HKS has no adjustment. Full atmosphere release.

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog
macipusy
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Re: Two BOV's

Post by macipusy »

I think you should run the recirc only. Keeps your turbo spinning between shifts and doesn't screw with the MAF metering and AFRs between shifts and during roll off throttle situations. There is absolutely no benefit from a BOV besides the noise and maybe less plumbing.
maciek puszynski

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CAV3MAN227
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Re: Two BOV's

Post by CAV3MAN227 »

-So I went ahead, hooked everything up and tested it. Same setup:

Image

-In the blue circle, is where I tee'd into the same line running to the HKS and boost gauge. What I noticed was, at regular driving, the bpv opens up, which is good for normal driving cause the air is recirculated. At high boost levels, you can hear the HKS open up, which is awesome for many reasons. Kinda like a 50/50 recirc/vented system.
-The only problem though, is while the car is sitting, and I rev it up, seems like nothing is opening up, I just get flutter out the intake. Would this be caused by running the same vacuum line to both bov/bpv's? If so, is there another line I can tee into to run separate vacuum lines to each bov/bpv's? The reason why I ask is, cause when I pull the vacuum line going to the bpv (not the HKS), and plug it with my finger, then rev it up, the HKS opens like normal.
-Any advise, hints, tips, criticism, etc. would be greatly appreciated.
macipusy wrote:There is absolutely no benefit from a BOV besides the noise and maybe less plumbing.
-Pretty much why I have it lol. I plan on going with a GFB bov when the cash comes around.

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog
macipusy
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Re: Two BOV's

Post by macipusy »

When the car is sitting you don't have much load on it when revving....so you don't really see boost, maybe a tiny bit. So you get very little air moving thru the BOV and bpv and it's not as loud as beetween shifts.
maciek puszynski

01 Impreza | v6 STi RA | 5mt | ej236t
93 Legacy Turbo | TW | 4eat | ej22t
16 WRX | 6mt | fa20
98 Legacy GT | wagon | 5mt | ej25d


2.36L Turbo - RSTi Build
CAV3MAN227
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Re: Two BOV's

Post by CAV3MAN227 »

-Okay, well here's another thing. Why would my car idle higher with a bpv than with the HKS? With the bpv its idling around 1200 rpms and with the HKS around normal, 700 rpms. kinda weird.

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog
Rubasu
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Re: Two BOV's

Post by Rubasu »

self learning ecu's got to love them....
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Legacy777
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Re: Two BOV's

Post by Legacy777 »

Can you draw a diagram of your intake and how you have the bpv & hks hooked up. Something's got to be plumbed up a little strange to cause the high idle.
Josh

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cj91legss
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Re: Two BOV's

Post by cj91legss »

Your bpv could need an adjustment. If its idling at 1200 then the iac is compensating for a vacuum leak.
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