Hks Bov?

[turbospd]

I saw this black nissan silvia on streetfire.net

http://videos.streetfire.net/search/silvia/1/9A7523FE-65AE-452A-868D-6DBD037591D4.htm

and it has the hks ssqv. The dual shudder sound after the bov goes off, seemed to go on for longer than you would normally hear. What would make this sound like this or does anyone know how that would work to get it to do that?

 

[tsunari]

How are your guys part throttle response? Reason I ask, is if I slowly let off the throttle say . . .modulating it around a corner @ peak grip, the car hessitates/bucks. I have yet to go out and log it with DSMLink, but it's definitely on the list of things to do.

As for setup, I have the adjustment screw backed out fully until it just barely touches the diaphragm, threads are sealed, dedicated VAC/BOOST source @ the intake Mani.

I'd really like to try and tune this out, otherwise if it's a side effect of the BOV, I guess I'll have to go with a different setup :-(

Everything else seems fine with a quick release of the throttle . . . with the usual flutter at low boost.

 

[olmytsi]

On old hks ssqv's you could, they took the bolts off on the new ones. I've seen this mis-info spread a couple times on these forums, next person's getting a warning for it.

Mine flutters, but only at low boost, on high boost it releases much faster. You can hear mine do both in this video as it transitions between the two different valves inside the ssqv.

http://www.youtube.com/watch?v=Um4Wxf6yurs

That sounds alot like my car when i had a 1g bov that was too crushed which was letting the air travel back to the turbo.

 

[EclipseTrbo420A]

How are your guys part throttle response? Reason I ask, is if I slowly let off the throttle say . . .modulating it around a corner @ peak grip, the car hessitates/bucks. I have yet to go out and log it with DSMLink, but it's definitely on the list of things to do.

As for setup, I have the adjustment screw backed out fully until it just barely touches the diaphragm, threads are sealed, dedicated VAC/BOOST source @ the intake Mani.

I'd really like to try and tune this out, otherwise if it's a side effect of the BOV, I guess I'll have to go with a different setup :-(

Everything else seems fine with a quick release of the throttle . . . with the usual flutter at low boost.

I got rid of that problem, wiht the custom job I did. It was alot of trial and error to get it right, but its works amazingly now! If I were you I would look for a type S and ru the top nipple to the intake mani and the bottom to an all boost,no vac source. You wont have that hesitation then.

 

[tsunari]

I got rid of that problem, wiht the custom job I did. It was alot of trial and error to get it right, but its works amazingly now! If I were you I would look for a type S and ru the top nipple to the intake mani and the bottom to an all boost,no vac source. You wont have that hesitation then.

So you're thinking it's probably a BOV related problem? If so I was considering two options:

1) Run dual SSQVs
2) Run a single TIAL


but I would hate to just start throwing money at a problem to try and fix it

 

[mavisky]

How are your guys part throttle response? Reason I ask, is if I slowly let off the throttle say . . .modulating it around a corner @ peak grip, the car hessitates/bucks. I have yet to go out and log it with DSMLink, but it's definitely on the list of things to do.

As for setup, I have the adjustment screw backed out fully until it just barely touches the diaphragm, threads are sealed, dedicated VAC/BOOST source @ the intake Mani.

I'd really like to try and tune this out, otherwise if it's a side effect of the BOV, I guess I'll have to go with a different setup :-(

Everything else seems fine with a quick release of the throttle . . . with the usual flutter at low boost.

Without a maft or speed/density setup of course it'll stumble. You're venting off metered air and causing the car to run rich for that second. Run a blow-through maft setup with your bov and you'll be just fine. You can hear how mine doesn't stumble at all in my video I posted because I'm venting before the maf.

 

[tsunari]

Without a maft or speed/density setup of course it'll stumble. You're venting off metered air and causing the car to run rich for that second. Run a blow-through maft setup with your bov and you'll be just fine. You can hear how mine doesn't stumble at all in my video I posted because I'm venting before the maf.

So you're saying a vented blow-thru setup would eliminate this problem as opposed to the recirculated setup I'm running right now?

 

[mavisky]

I was never a fan of my hks re-circulated. Works much better in the vented mode, not sure why, but it just does.

 

[tsunari]

I was never a fan of my hks re-circulated. Works much better in the vented mode, not sure why, but it just does.

Hehehe. . . probably because it was designed to run like that

I'm planning on switching to blow-thru, just need pipes and the translator.

So you sayin that under part throttle lift, you have no hessitation/stumbling/etc ??? Because this problem has plagued me since the beginning of the car (even with the stock BOV me thinks . . . but that was quite a while ago)

 

[mikyrc]

Hi guys.

Mavisky, are you shure the sound of that video is the transitions between the two valves?

I say that because mine sounds exactly like yours and i always thought that it was compressor surge.

That's the sound of mine (not very clear though):
http://www.yousendit.com/transfer.php?action=download&ufid=31916B8F1E211303

If that sound is the valves, then you really made me happy man!

EclipseTrbo420A, i was thinking to do something similar to what you've done to the ssqv, but instead of adding a nipple on the rear chamber, it's a lot easier to just drill a hole from the valves chamber to the rear diaphragm chamber (chambers A to B in your drawing). You end getting the same boost source as you did with the nipple.

Thanks guys.

 

[mavisky]

That sure sounds like the small valve to me in your video, and yes I'm sure that's the small opening on mine. With a properly tuned MAFT setup in blowthrough mode I have no stumbling mid-throttle what-so-ever. You can hear in that video the way I pedal the power through that turn, you can hear it release a bit, then throttle, then release again with no delay or bucking in between.

 

[EclipseTrbo420A]

Hi guys.

Mavisky, are you shure the sound of that video is the transitions between the two valves?

I say that because mine sounds exactly like yours and i always thought that it was compressor surge.

That's the sound of mine (not very clear though):
http://www.yousendit.com/transfer.php?action=download&ufid=31916B8F1E211303

If that sound is the valves, then you really made me happy man!

EclipseTrbo420A, i was thinking to do something similar to what you've done to the ssqv, but instead of adding a nipple on the rear chamber, it's a lot easier to just drill a hole from the valves chamber to the rear diaphragm chamber (chambers A to B in your drawing). You end getting the same boost source as you did with the nipple.

Thanks guys.

Hey, Yes that exactly how the SSQV comes from the factory. I forgot to add in my drawing the little pin hole that runs next to the one way valve. THats how the ssqv pressurizes both chambers then when vaccume is present it sucks the pressure out of the rear chamber AND the middle one through the bleeder hole. The only Ill effect I can think of with drilling that hole is how big the diameter will be. the reliefe vavle from the factory is literally about the sive of a pin tip. Goodluck all I know is mine works GREAT the way I have it set up. GoodLuck.

 

[mikyrc]

And about your iddle problem?
What's exactly happening?
Will i have iddle problems too?

With your mod the BOV will keep open on deceleration and iddle, don't?
I think that the way they designed the two chamber sistem with the check valve is for the valve to not stay open during decelerating and at iddle (under vacuum).

 

[EclipseTrbo420A]

And about your iddle problem?
What's exactly happening?
Will i have iddle problems too?

With your mod the BOV will keep open on deceleration and iddle, don't?
I think that the way they designed the two chamber sistem with the check valve is for the valve to not stay open during decelerating and at iddle (under vacuum).

My mod makes the bov closed at anything or anytime, accept when the pressure in the intercooler piping leading to the nipple ( middle chamber ) exceeds the pressure in the rear chamber+ what ever the spring rate is back there. Heres how it will work

If your doing a 2-4th gear pull and now at WOT when you hit the clutch and let off the throttle--the TB plate will close...When that happens the Intake manifold will now be under vaccume for that fraction of a second between shifts and suck the pressure out of the rear chamber thus trying to open it, but the spring is stronger than the vaccume so its not quite going to open. AT THE SAME TIME all that happend when the throttle plate closed, the intercooler piping becomes pressurized alot higher than the boost you are running because the turbo is forcing air into a now closed circut. Thats when the BOV and our mod come in. When that happens the pressure builds in our new nipple to the middle chamber so fast that it blows the diaphram up and compresses the spring, opening the bov untill the pressure in the middle chamber ( which is also IC piping pressure ) dies down BECAUSE the BOV worked properly and blew off that pressure back into the intake.

So at de-acceleration if you let off the throttle and keep the car in gear the IC piping will become pressurized for a quick moment [ IF you were on the throttle moderately] ( Thats why when you hear a 1G BOV give the long whistle because its to weak to hold pressure even there. ) When Im deaccelerating I hear a QUICK CHUUuuuuuuu, just releasing enough pressure to keep it from getting back to the turbo ( IF im boosting hard and let off I get a BIG crack like a whip that turns into a Chooo after some of the airs been bled off. SO under de-accel the spring will keep the bov from opening unless theres more pressure in the IC piping to over ride the spring pressure minus vaccume pressure, and thats only acheivable by a spooling turbo right to a quick pedal lift while still in gear which is normal for Dailydriving or anykind of driving. My point is The bov will work like its suppsed to and I havnt had any problems. If you want a step by step on what I did, Im sure I could gather the info up. -MattD

 

[mavisky]

I didn't realize people were having that big of a problem with the hks bov on deceleration. Listen to my video again and you can hear me hit it twice hard between 4500-6000rpm and with the 18g there's a release, instant boost again, then another release within half a second.

 

[EclipseTrbo420A]

I didn't realize people were having that big of a problem with the hks bov on deceleration. Listen to my video again and you can hear me hit it twice hard between 4500-6000rpm and with the 18g there's a release, instant boost again, then another release within half a second.

Mine would surge all day long before I did this. It would make the car buck and die out between shift and even stall on a blow off....I though my recirc system was messed up or something anyways Im glad I got it cleared up not I have alot of good stuff going on the car soon.

 

[mavisky]

n/m just realized you're still re-circing it on a stock maf.

I wouldn't reccomend the hks ssqv unless its vented properly. When mine was re-circed it had some slight stumble issues at times, but never anything major.

 

[EclipseTrbo420A]

n/m just realized you're still re-circing it on a stock maf.

I wouldn't reccomend the hks ssqv unless its vented properly. When mine was re-circed it had some slight stumble issues at times, but never anything major.

Yea im still on the stock mas, I have DSMLINK comming in about 2days I hope and didnt opt for the MAFT because I read it pegs your intake temps at 32 and thats just something I dont want. As of now though, no stumbling or anything everything works as it should.

 

[olmytsi]

It pegs the intake temps at 79 degrees, not 32

 

[EclipseTrbo420A]

It pegs the intake temps at 79 degrees, not 32

I read it awhile ago... I just know Since I dont need it right now and Id rather not "peg" my intake temps that im not getting it. I cant wait for link to get here. I have ACT 2600 , fidanza flywheel, prothane motor mounts, that SS fmic new wires, battery relocation and DSMLINK all about to go in. Just waiting for link to arrive!

 

[mavisky]

Link is better, but I like the maft for its price point. I'm running just it on my FIC 650's and the car runs great. No eprom chip, no s-afc, afpr is set at base levels.

 

[EclipseTrbo420A]

Link is better, but I like the maft for its price point. I'm running just it on my FIC 650's and the car runs great. No eprom chip, no s-afc, afpr is set at base levels.

I hear ya there, but unfortunaly I cant log knock...just dips in timing and I got sick of that. I figured since I believe im probably going to keep this car forever ( paid off ) and I love it that Ill start getting the best for it. As soon as I get out of college this is getting a major overhaul and Ill pick up a nice DD.

 

[mikyrc]

Thanks Matt, as i read you had some iddle problems i thought it could be related to the BOV moddification you did. But if you say it runs great that's cool.

I'll try to vent it to the atmosphere first and see if it runs better. If not maybe i'll do the mod too.

 

[EclipseTrbo420A]

Thanks Matt, as i read you had some iddle problems i thought it could be related to the BOV moddification you did. But if you say it runs great that's cool.

I'll try to vent it to the atmosphere first and see if it runs better. If not maybe i'll do the mod too.

Hey No problem, but if anything vent correctly dont just pull the recirc tube....I would rather have a slight stumble than have my ecu giving fuel for air that isnt present. I say get the maft and vent correctly ! Goodluck man.-Matt D.

 

[mavisky]

Hey No problem, but if anything vent correctly dont just pull the recirc tube....I would rather have a slight stumble than have my ecu giving fuel for air that isnt present. I say get the maft and vent correctly ! Goodluck man.-Matt D.

Agreed, I don't want anyone to take my statement regarding venting the bov vs. recircing it to mean that they should vent on the stock system. When I was for a short period I noticed huge hesitations and bucking when getting off the throttle. What I had for years perceived as nothing major was quickly realized once I was venting correctly using the blow-through method of the maft.

 

[mikyrc]

Hey guys, i've been doing some tests with the ssqv.

First i tried to vent to the atmosphere and surprisingly the car wasn't stalling like the 1G does when vented. The only thing is that still flutters and the sound is too loud to me.

The car still does shake when letting off the throttle at light throttle and low boost (just as it did when recirculating). As somebody said that BOV seems to be like an ON/OFF switch, if you try to drive smoth at light throttle the car shakes a bit as it doesn't open.

I attach you guys a sound file of my bov venting to the atmosphere, So you can hear it:

http://www.yousendit.com/transfer.php?action=download&ufid=EA11B55E6D48458A

Then today i tried to do the Matt (EclipseTrbo420A) mod. Well i have to say that the car felt super smoth, no partial throttle problems, very driveable at light throttle, no shaking at all.
But the big problem is that the BOV sound totally disappeared.
It doesn't even sound like the stock BOV, you only hear a tiny "psshhh" almost not notticeable. My 1G Bov was much louder than that.

And also you can't vent to outside anymore as the Bov stay open at iddle, even with the bolt tightened at maximum.
If i had a stiffer spring i could test it and see if it improves, but i doesn't have it.

I don't know what i'll gonna do. I bought the BOV because of the cool sound it does, but if i have to drive it like this i'll put back the 1G.
Or undo the SSQV mod and drive the car with some bucking and a cool sound again.

EclipseTrbo420A, how does your BOV sound?