DSM BOV NFG?

[Edub1]

I think my BOV is NFG. The sound it makes is more like compressor surge than a healthy BOV sound (I think) It makes a brief squeek followed by a rapid fluttering sound that kinds of sounds like russling leaves.

I noticed this BOV does have some small allen bolt in the bottom - don't know if this is an adjustment or what. Anybody know what's the deal with this thing?

I guess I could shove a wad of cotton in and see if it blows it out but still, I cringe when it makes that sound.

[90SRpwrd240]

The fluttering sound that you are getting is the result of back pressure on the Turbo. This could be caused by the blow off valve spring not being adjusted right. Sounds like you need to loosen up that screw a little bit so it will open at a lesser pressure so you can let that air out, which should stop the back pressure...someone correct me if I am wrong lol

[Chezedik]

DSM doesn't have an adjustment. Unless it is modded.

What is your boost level? Can you post a wav? You still using that T3?

You could just do what I want to do, and put a duck call in the outlet, so when it blows off it will quack! Now that is JDM!

[90SRpwrd240]

You could just do what I want to do, and put a duck call in the outlet, so when it blows off it will quack! Now that is JDM!

HaHaHaHa The duck call is hilarious http://www.youtube.com/watch?v=Erjhkv9AzKY

[Chezedik]

I know, right?!?!

[Edub1]

OK, I tested the BOV by just reving motor and looking inside. This BOV is open at idle and closes when motor revs so it is entierly unsuitible for atmospheric dump.

Still heard a little fluttering under just a driveway rev with no appreciable boost - maybe 0.5-1 psi. Could the 3/4" ID hose I'm using be too small?
Modified by Edub1 at 6:24 PM 3/26/2007

[Chezedik]

That is how they do. If you need a hotwire correction, try SAFC or emanage. Also, you should be able to pull fuel at the bottom of your map and it should be okay.

If you are using 3/4" hose to recirc and it is fluttering, you may just have to deal. It is not surge, it is just BOV flutter. It happens on lots of setups. You can have yours crushed if it really bothers you. Also, you can egg out the holes and put a Type RS on.

[NateDogg]

High Pressure Bosch:

http://www.saabperformanceparts.com/item140.htm

[Edub1]

Here is what it sounds like - and it's funny as hell.http://www.youtube.com/watch?v=Fsw5aAscpeY&NR

[eazye2000]

THAT is some good s***!

[Edub1]

I think I might have found the problem. Refference hose to small. Going to upsize from 3/16" to 1/4"

[Chezedik]

You mean vac reference? Good deal, I have 1/4" now, good deal.

[Edub1]

I might change the recirc hose as well from 3/4 to 1" ID

[Chezedik]

Do you still have an SAFC or anything lying around? Why not just go atmospheric?

[Edub1]

Never owned an SAFC. The DSM BOV, like many others, is actually a recirc valve that stays open at idle. I just learned this and am now re-tuning my car to compensate for the colosal vacuum leak I wasn't aware of before recirculating.

I made a post about this that should probably be stickied.

[Chezedik]

It's not really a vacuum leak. It is what it is, a leak on the pipe. But you are right, mine is normally open, plus I was using a port vacuum line, which made it virtually worthless, so I am moving the vacuum line.

Can you not pull a lot of fuel in the upper left corner of the map? That way when you would run rich from blowing off, the extra fuel can be used to run the car. Also, it will save fuel at idle when you aren't boosting anyway. This should work fine unless you are AutoX, then it might cause detonation.

What do you think about that?

[Edub1]

I can't think of any way to tweek the map for it because you never know where on the map you will be when you let off throttle. The SAFC probably reads the TPS and makes a quick cut when it senses a decel.

Besides, air is coming in through the open valve. I'm going to try running a larger hose.

[Chezedik]

Incoming air is not necessarily a vacuum leak, though. Just unmetered air.