Greddy Type S BOV nipple question

[bjoseph04]

Could someone tell me what the 2nd nipple on the lower side of the Greddy Type S bov is for? I have a T and a hose in my install kit ( no manual ) and I thought someone said it ran down somewhere by the wastegate? If so which lines do I splice into the T? I notice theres already a T formed right before the wastegate where the lines coming from the boost selenoid and something else meet together and then the hose that runs to the wastegate nipple... so could someone be extremely specific as to how I hook the 2nd lower nipple on the BOV up? thanks a bunch

 

[95TalonOwner]

You don't have to hook it up. Just leave it how it is and don't cap it. If you cap it, the BOV will not work right.

 

[diablos991]

That nipple is for a preasure source. I spliced mine into the line that runs to the turbine housing.

F.Y.I.: When I installed my EBC it caused problems when I spliced it into the line running to the wasegate. I had to resplice it to the turbine housing line.

 

[bjoseph04]

Where at exactly can you give me a picture or somethin ima newb the turbine housing nipple is where?

 

[MrBoxx]

diablos, do you mean the compressor housing nipple instead of the turbine housing?

bjoseph04, don't worry about hooking up the second nipple. If you want to tie it into a boost source, you may get better BOV response, but that's really all it's for. It seems most people just prefer not to bother with it.

 

[bhop]

Leave it open. It may be for a pressure source for specific applications, but for DSM's it's supposed to remain open.... it even says so in the instructions.

 

[diablos991]

diablos, do you mean the compressor housing nipple instead of the turbine housing?

Ya, I meant compressor housing. I was just unsure of the terminology at the time. But as to hooking up that line to a pressure sourse, I have tested both ways and find no performance difference at all. The only thing that I notice is that it makes it a heck of a lot louder when it is connected.

If anybody knows of any performance difference by routing it this way let me know. I searched and haven't found one yet, but I would love to have a for sure answer.

~Shawn

 

[ericbev]

Compressor surge at light throttle lifts can be further reduced by connecting the lower fitting to a pressure source. Typically a fitting is added to an I/C pipe between the turbo and the BOV to use the trapped pressure to help push open the valve during these low pressure change conditions. Although slightly more involved, this method allows for crisp on/off transient response inbetween gears without the reoccurrence of surge.

Typically when your BOV is set "tight" you can really feel the boost come right back on inbetween gears, but you get compressor surge at lower throttle releases. Most cars that have their BOV tuned for everyday driving are set a little softer then they would like just so they aerent getting the deadly compressor surge. I usually tighten up my BOV a little when going to the track to ensure that the spring closes as fast as possible to help pressurize the intake tract with maximum efficiency. The above mod will allow you to run a slightly "tighter" spring tension setting in an everyday setting without allowing compressor surge to rear its ugly head.

 

[alIan]

If you do decide to leave the lower nipple open, and you decide to get a large enough turbo (that flows a lot of air between shifts), then you will most likely run into problems. The lower nipple being unplugged allows some air to be released into the engine bay. With a T-25 or so sized turbo, and probably even up to a 20G, this isnt going to give you a problem because the wheels are so small that they dont have the momentum to push out a lot of air when they are not being driven by exhaust. However, if you decide to upgrade to a 50trim+, you will most likely lose enough air between shifts that if you do not get into a gear short after (i.e. let it drop to idle after a boost), it will cause a stall due to extremely rich conditions. The computer has no way of keeping track of the air lost through that nipple if it is not part of the loop, unless you have an airflow sensor after your BOV. This is a situation very similar to "venting" a BOV in a stock DSM.

 

[destrux]

You shouldnt be venting a greddy or ANY bov if you have an airflow meter before the bov. It causes a bog no matter how the BOV is setup, you may not notice it if the bog is small, but it's still there taking away power.

 

[DSMunknown]

http://herpetology.com/dsm/bov.html

 

[daren_p]

Like everyone has said most leave the second "lower" nipple not connected & vented to atmosphere. If you do connect it up it needs to be connected to its own pressure source. Connecting this line up makes the BOV function the exact same way as a 1g BOV does (ever notice that hole in the bottom of a 1g valve?) its directed under the diaphragm, as is the second lower nipple on the type S valve. This allows the valve to be quicker acting, but will blow open quicker/easier so you will probably have to tighten the spring tension to compensate.

destrux: alIan isn't talking about ventening the BOV hes talking about the lower fitting & venting. But alIan unless the Type S is different (which I highly doubt as far as "make up" of the valve, not talking differences that don't matter such as valve size etc) then the Type RS, this isn't true. While that fitting is located under the diaphragm (top fitting that is always connected is above diaphragm) it is still in a seperate chamber then the area that "vents" the ic pipe air back into the intake. There is a seal around the valve piston shaft that seals these two compartments from each other.

 

[FenixTX717]

ok, after all this, i'm still not clear on to where to connect the lower nipple on the greddy type s? Is there a picture or can someone snap some shots on to where a good source to tap in a line from the lower nipple to whereever it goes to? I'm a picture person myself and i'm not understanding where you guys are talking about to run a line to it....

everyone says it's better to plug it in somewhere than to just leave it open....

 

[oldman]

everyone says it's better to plug it in somewhere than to just leave it open....

Leave it open unless your BOV sounds like a turkey call (specifically during part throttle blow off) even after properly adjusting you adjustment rod. To further understand the purpose, though already explained by ericbev and daren_p, read this Dodge moded 1G bov ariticle. If in fact you still feel the need to connect it to something, do not T it off anything, you can use one of the pre-TB fittings on your throttle plate if you have removed some of your vacuum lines.

As for what alIan posted, no you will not lose air through that fitting if it's left open.

 

[FenixTX717]

well my main reason i wanna hook it up is because everyone says it's louder and it responds faster and it's better for the bov to be hooked up....is there a picture of where the best place to hook it up too at? or could someone snap a quick pic for me....i'm just not understanding it at all...i feel stupid ### i just don't comprehend where it goes?

 

[booosting92tsi]

check this out it might help

Picasa Web Albums - Booosting 92 - GREDDY TYPE S...

I got boost spikes with the second nipple connected, so I went back to the original setup, works fine now!

 

[diablos991]

check this out it might help

Picasa Web Albums - Booosting 92 - GREDDY TYPE S...

I got boost spikes with the second nipple connected, so I went back to the original setup, works fine now, why would connecting the 2nd nipple cause major boost spikes?

Wow, this is an old thread.

Often times when people are experiencing boost spikes with the second nipple hooked up, it is because of where they spliced into a pressure source.

 

[booosting92tsi]

Wow, this is an old thread.

Often times when people are experiencing boost spikes with the second nipple hooked up, it is because of where they spliced into a pressure source.

So exactly where in the boost source do you connect it to?
There are 3 scenarios:
1) is if you have the stock BCS setup
2) is if you have a MBC setup
3) is if you have an EBC setup

Picasa Web Albums - Booosting 92 - GREDDY TYPE S...

I learned the boost spike was because when the lower nipple gets connected between the turbo outlet pipe and the wastegate actuator, this would interrupt the signal going to the wastegate actuator messing up the REAL/ACTUAL boost, causing it to spike erraticly! In my case I still had the stock BCS setup.

 

[diablos991]

So exactly where in the boost source do you connect it to?
there are 2 scenarios, one is if you have the stock BCS setup and the second scenario is if you have a MBC!

Picasa Web Albums - Booosting 92 - GREDDY TYPE S...

I learned the boost spike was because when the lower nipple gets connected between the turbo outlet pipe and the wastegate actuator, this would interrupt the signal going to the wastegate actuator messing up the REAL/ACTUAL boost, causing it to spike erraticly! In my case I still had the stock BCS setup.

There are actually 3 scenarios. I have the third: an EBC.
I currently do not have the second nipple hooked up until I get time to thread a nipple into my UICP.

 

[booosting92tsi]

There are actually 3 scenarios. I have the third: an EBC.
I currently do not have the second nipple hooked up until I get time to thread a nipple into my UICP.

So why the UICP? Is that the best "boost only" source for Greddy BOV lower nipple? what's the reasoning to tap into the UICP?

do you have any kind of diagram of your EBC setup?

 

[diablos991]

So why the UICP? Is that the best "boost only" source for Greddy BOV lower nipple? what's the reasoning to tap into the UICP?

do you have any kind of diagram of your EBC setup?

The way that an EBC is set up is almost identical to an MBC. The solenoid is hooked up just as if it were an MBC. I have one line running to the compressor housing on my T-28 and one line running to the wastegate.

I am not sure if the UICP is the best source for the Type-S or not. It just makes logical sense to me for the following reasons:

The lower nipple needs pressure when under boost, the UICP (post BOV) nipple would be the shortest route for a vac line, it doesn't splice into anything, and when you are under boost you will have plenty of pressure to that nipple.

 

[16G AWD]

my j-pipe has a nipple on it. should i just run a hose from that to the stock boost controller? right now i have my hose from the top bov nipple to the intake manny but teed off going to the j-pipe.

 

[kanderson]

I'll try to explain this as clearly as I can.

The upper nipple on a Greddy type-s goes to your intake manifold so that it sees boost or vacuum, depending on whether you are on the throttle or not. The lower nipple can be connected to a constant boost source (uicp), or left unconnected with the result of a slightly slower BOV actuation and maybe slight compressor surge. The lower nipple goes to a completely different chamber from the top nipple, and the only way you will get a transfer of air between these two chambers is if you have a torn diaphragm. However, this lower chamber is NOT sealed from below. In other words, a limited amount of air can pass from this lower chamber into your preturbo intake (out the side opening, where the "blown off" air goes), essentially recirculating a small amount of hot air. This means that you do lose a small amount of boost through connecting this nipple, and it also means that you DO NOT want to tee it into the line going from the compressor housing to the BCS because the line is so small that enough air can recirculate through the lower nipple to keep the BCS from registering full boost. This causes uncontrolled boost (23 psi in my car) as the BCS never tells the wastegate to open. If you want to see for yourself, take your type-s out and blow into the lower nipple. I did this and could easily blow air through. When I sealed the large side opening with my hand I could feel pressure changes as I blew out and sucked in.

Hope that will clarify things a little

 

[kanderson]

Forgot to mention that if anyone does test theirs and it holds pressure, mine could just be a bad example of a type-s. However, they don't have any rubber seals from the lower chamber down (the only "seal" is metal on metal), so I assume they are all the same? I might try to seal this with silicone to eliminate any leaks, I'll get back later to reveal if it works.

 

[booosting92tsi]

I'll try to explain this as clearly as I can.

The upper nipple on a Greddy type-s goes to your intake manifold so that it sees boost or vacuum, depending on whether you are on the throttle or not. The lower nipple can be connected to a constant boost source (uicp), or left unconnected with the result of a slightly slower BOV actuation and maybe slight compressor surge. The lower nipple goes to a completely different chamber from the top nipple, and the only way you will get a transfer of air between these two chambers is if you have a torn diaphragm. However, this lower chamber is NOT sealed from below. In other words, a limited amount of air can pass from this lower chamber into your preturbo intake (out the side opening, where the "blown off" air goes), essentially recirculating a small amount of hot air. This means that you do lose a small amount of boost through connecting this nipple, and it also means that you DO NOT want to tee it into the line going from the compressor housing to the BCS because the line is so small that enough air can recirculate through the lower nipple to keep the BCS from registering full boost. This causes uncontrolled boost (23 psi in my car) as the BCS never tells the wastegate to open. If you want to see for yourself, take your type-s out and blow into the lower nipple. I did this and could easily blow air through. When I sealed the large side opening with my hand I could feel pressure changes as I blew out and sucked in.

Hope that will clarify things a little

you're kinda late with your post, tell us something new that we don't know, everything you just wrote, well all already know about it! nice way to summarized it though