Anyone with a type-s bov?

[canadiandsm11]

I just installed a greddy type-s that I bought off someone online. Before I installed it, I opened it up to check the diaphram for any holes or tears; there were none. When I start the car, the unit leaks quite badly. I can only make it not leak under idle by tightening the adjusting screw on top about 90% in, but when I do that, the valve will hardly open under boost and I get compressor surge.

Just trying to wrap my head around why this is leaking like this. If anyone has any ideas, please enlighten me!!!

 

[tkelly27]

Is it leaking, or is it just opening? If it's just opening, that's normal. Get a recirc kit and you'll be fine. If it's leaking... you've got me.

 

[canadiandsm11]

It stays open. If the adjustment screw is down 90%, it will be shut but then I get compressor surge. Once its a bit looser, it'll be open at idle and no compressor surge.

I was thinking about the recirc kit, since that's why I changed to the type-s. I wasn't planning on doing that right away though. It can't be that the type-s is a recirc. bov solely. I've seen others (youtube, etc) that run it vented.

 

[Mikael SS]

It stays open. If the adjustment screw is down 90%, it will be shut but then I get compressor surge. Once its a bit looser, it'll be open at idle and no compressor surge.

I was thinking about the recirc kit, since that's why I changed to the type-s. I wasn't planning on doing that right away though. It can't be that the type-s is a recirc. bov solely. I've seen others (youtube, etc) that run it vented.

I don't know anything about it, but the above post says its fine for it to be open at idle. Of course its not good for the motor sucking in whatever it wants, to prevent that put a filter on the BOV or recirc it.

as soon as you hit the throttle the vacuum will go away and it'll close, allowing you to boost.

 

[Twinky-Ninja]

You can run it vented, but you'll need to run your maf after the bov, that way your not venting metered air. This is common with a GM maf/maf translator in the blowthru configuration.

*Edit- Putting a filter on the bov won't help the situation. Sure you'll preventing some foriegn objects from entering the intake tract, but you'll still be losing metered air at idle and high vac instances.

 

[sd_ff22]

the BOV is supposed to be open at idle. At idle on a well running car you should see 15-20in of vacume.
It CAN NOT be vented, unless you are useing a GM maf and MAFT.
The BOV will not suck anything in at idle because it is protected from the outside air by the main intake filter.

start with the adjusting screw a few turns in and take a drive. keep adjusting it down until you get a good feel to the throttle response and the shift. NOT UNTIL YOU THINK IT SOUNDS GOOD.

A BOV is to protect your turbo and engine. Sound is secondary.

-Dan

 

[awesome_asim187]

Are you sure you are hearing the leaking from the BOV? Where is it located?

 

[Boostjunki84]

the BOV is supposed to be open at idle. At idle on a well running car you should see 15-20in of vacume.
It CAN NOT be vented, unless you are useing a GM maf and MAFT.
The BOV will not suck anything in at idle because it is protected from the outside air by the main intake filter.

start with the adjusting screw a few turns in and take a drive. keep adjusting it down until you get a good feel to the throttle response and the shift. NOT UNTIL YOU THINK IT SOUNDS GOOD.

A BOV is to protect your turbo and engine. Sound is secondary.

-Dan

+1...

 

[viperlp01]

I don't know. My car responds absolutly fine with it unrecirc. I do not surge or have an idle problems. I have 20 vaccuum at idle and when i let her rev down i hit about 25 vac. Mine is close at idle. I wonder if you have a bad spring. A maf-t will not change the fact that your bov is sucking in unfiltered air. Mine does not suck in any air at idle so i think you got that part wrong. There are also tons of threads on here debating the fact about having it vented or not and having it vented does not hurt your motor and will not allow foriegn objects to enter. You run rich for about .2 secs when you shift.

 

[Boostjunki84]

I don't know. My car responds absolutly fine with it unrecirc. I do not surge or have an idle problems. I have 20 vaccuum at idle and when i let her rev down i hit about 25 vac. Mine is close at idle. I wonder if you have a bad spring. A maf-t will not change the fact that your bov is sucking in unfiltered air. Mine does not suck in any air at idle so i think you got that part wrong. There are also tons of threads on here debating the fact about having it vented or not and having it vented does not hurt your motor and will not allow foriegn objects to enter. You run rich for about .2 secs when you shift.

To the performence minded, .2 seconds is a lot.

 

[DSM_PWR]

is it leaking or are u sure its not the lower nipple making a hisss

and every car is different, my friend can run his car without a maft/gm maf stock ecu and still vent to atmosphere. but if i try it..i cant even idle.

 

[sd_ff22]

I don't know. My car responds absolutly fine with it unrecirc. I do not surge or have an idle problems. I have 20 vaccuum at idle and when i let her rev down i hit about 25 vac. Mine is close at idle. I wonder if you have a bad spring. A maf-t will not change the fact that your bov is sucking in unfiltered air. Mine does not suck in any air at idle so i think you got that part wrong. There are also tons of threads on here debating the fact about having it vented or not and having it vented does not hurt your motor and will not allow foriegn objects to enter. You run rich for about .2 secs when you shift.

It has also been covered 11ty billion times that no matter how well you THINK your car is running vented, you are hurting something. Case in point, I notice that you do not refrence a loggers results in that your car is running "absolutly fine". Start there my friend. yours is closed at idle if you adjusted it that way. the BOV is SUPPOSED to open at idle vacume. thats how it does its job of being a compressor bypass valve.

run a logger on your car and start looking at your timing curves, short and long term fuel trims.

Please do more research. A loud BOV DOES NOT = a fast car(.)


-Dan

 

[DSM_PWR]

It has also been covered 11ty billion times that no matter how well you THINK your car is running vented, you are hurting something. Case in point, I notice that you do not refrence a loggers results in that your car is running "absolutly fine". Start there my friend. yours is closed at idle if you adjusted it that way. the BOV is SUPPOSED to open at idle vacume. thats how it does its job of being a compressor bypass valve.

run a logger on your car and start looking at your timing curves, short and long term fuel trims.

Please do more research. A loud BOV DOES NOT = a fast car(.)


-Dan

CORRECT... now if you could explain that to my friend i would get $50 for the bet

 

[sd_ff22]

CORRECT... now if you could explain that to my friend i would get $50 for the bet

sure, whats the bet on?

-Dan

 

[DSM_PWR]

when we run a logger both vented and recirculate he will see the difference. EZ money

 

[sd_ff22]

All you have to worry about if you are using the same car for both tests is that it will take a wile for the ECU to re-adjust to running PROPERLY.

-Dan

 

[DSM_PWR]

na gunna use the same car. then ima sell him the intake w/recirc layin around for $50

 

[canadiandsm11]

Hey thanks for the replies, guys.
As far as the vented vs recirculated, I know the cons of running vented and that's why I want to recirc, but like I said before, I wasnt planning on doing that right away. Before this greddy, I was running a different bov that only vented to atmosphere. At idle it was completely closed, and I never had any side effects (stalling). I knew it ran rich between shifts (using logger), but again, thats why I'm changing to a recirc.

The reason for me starting this thread wasnt to debate vented vs recirc, but to figure out why this valve is either too tight and properly vent, or too loose and it'll leak/open at idle. It's definitely not the nipple, but the valve just not shutting completely.

So my question, I guess, has boiled down to this. Is the type-s a recirc ONLY bov, neverminding the general cons of venting and pros of recirculating? Even if it is leaking a bit under idle if the adjusting screw is out more, will it actually be closed under cruise, part throttle, vaccuum? I guess I could just recirc right away, but I dont want that to be a band-aid solution just because my greddy is faulty in some way.
\thx

oh, and does anyone know if the type-rs spring works in the type-s?

 

[viperlp01]

Why do people vent when they get a maf-t?? This whole thing is stupid to begin with. I wish i saw the numbers of time that use lose with it vented to unvented. It is probaly small.

 

[canadiandsm11]

Does anyone know if the type-rs spring works in a type-s by any chance? And if there are any vendors here, can you get a replacement spring for the type-s?

 

[tkelly27]

Hey thanks for the replies, guys.
As far as the vented vs recirculated, I know the cons of running vented and that's why I want to recirc, but like I said before, I wasnt planning on doing that right away. Before this greddy, I was running a different bov that only vented to atmosphere. At idle it was completely closed, and I never had any side effects (stalling). I knew it ran rich between shifts (using logger), but again, thats why I'm changing to a recirc.

The reason for me starting this thread wasnt to debate vented vs recirc, but to figure out why this valve is either too tight and properly vent, or too loose and it'll leak/open at idle. It's definitely not the nipple, but the valve just not shutting completely.

So my question, I guess, has boiled down to this. Is the type-s a recirc ONLY bov, neverminding the general cons of venting and pros of recirculating? Even if it is leaking a bit under idle if the adjusting screw is out more, will it actually be closed under cruise, part throttle, vaccuum? I guess I could just recirc right away, but I dont want that to be a band-aid solution just because my greddy is faulty in some way.
\thx

oh, and does anyone know if the type-rs spring works in the type-s?

The good news is your BOV is functioning perfectly. The bad news is that you're not recirculating it.

Haha, sorry to be a smart ass, but a BOV will be open under normal idle conditions. There are two conditions where this is not so, #1, a design which doesn't open without boost and #2, as you've figured out, when you're running enough spring tension to keep it shut at idle.

The problem with #2, as you've also figured out, is that it takes a lot of boost to pop that sucker open when the spring is set so tight.

You've noticed that when you blip the throttle, the bov shuts. This is because the vacuum in the manifold has decreased to the point where the spring can overcome it and close the valve. An interesting thing happens as soon as you start making boost in your manifold, the pressure from it actually pushes down on the diaphragm and forces the valve shut even harder.

Designs that do close at idle may have a smaller diaphragm, putting less pulling open force onto the valve. I wouldn't know which ones these are, because I always am running a recirc setup or speed density.

I don't know of any modification that will remedy the opening under idle problem other than a different BOV, tightening the spring until it no longer opens properly, recirculating properly, MAFT, or a speed density system. The only true solution to it, are the last 3.

I don't know what the others that you've seen run it are doing. Perhaps they have compensated for the leak in the tuning, maybe they've gotten the spring just perfect, maybe god touched their engine bay. I had an uncirculated RFL on my car when I got it, it was setup just on the edge. One less washer it would open, one more washer and it would stop blowing off at a reasonable boost level.

I know you know running uncirculated is bad, but I don't know if you know how bad. From running that way for about a month, the exhaust manifold and cylinder head were coated .5mm thick with carbon, the turbine blades were coated, as well as the turbine, O2 sensor, O2 housing, just not as thick. It's just a bad idea dude, no matter how long you want to run it for.

 

[97 gst turbooo]

I had a problem with my greddy type s being open at idle causin it to idle high. After adjusting it stiffer or looser same problem. HKS ssqv took care of the problem.

 

[JusMX141]

Why do people vent when they get a maf-t?? This whole thing is stupid to begin with. I wish i saw the numbers of time that use lose with it vented to unvented. It is probaly small.

The 3" GM mass airflow sensor is moved to a location in the piping AFTER the blowoff valve, you are able to vent because the air exiting the blowoff valve hasn't been metered by the MAS yet. When you set a GM MAS up as draw-thru, in the same pre-turbo location as your stock MAS, you'll still need to recirculate. This is another common misconception.

Why would true DSM performance guys want to vent? Eventually when you start running 30+ psi, you need to have a larger BOV that will drop the large volume of air in the piping as quickly as possible between shifts so you do not surge and damage your turbo. If I needed to drop a large volume of air quickly, I would insist on using a Tial 50mm blowoff valve. They're freakin' huge.

You must be logged in to view this image or video.

A stock DSM BOV, as well as those overpriced models made by Greddy and half of the other aftermarket companies on the planet are still too small to handle airflow of this volume, but they sure do look and sound purdy!