[Evochuck]

Since our cars are running with MAP sensors, its pretty safe to say the only reasons the air is plumbed back into the intake is for noise reasons (beacause a lot of ppl dont want a 55k car to woosh everytime they shift). FYI if you plan on installing an intake or DCI, it will make your install 2x easier

Before you stat the install you will need a few things:
-A good rachet kit
-7/8 rubber leg feets (7/8 is the inner diameter)
-1 inch worm clamps (for safety measures)



1) Unclip the top of your intake and remove it

2) Remove the air filter

3) Loosen the 2 worm clamps connecting the air box to the intake pipes(1), deattach the 3 cables running behind the box (2)(a nice upward tug will take em off), disconnect and move to the right the vac hose in front of the box(3).



4) Once this is all done, gently take unplug the 2 box outputs(filtered air) and the input (4)(i found that completely removeing that part made reinstallation easier, removed with 2 hex bolts on rad support)

5) Pull intake up and then towards you to remove it

6) You can now clearly see the DVs alonmg with their plumback tubes, disconnect the tubes from the piping by rotating the gray part of the connector and then pulling the tube.( stuffing you intake with rags is usualy a good idea since anything falling in there with go through your turbos)




7) Install rubber feet on tube end and secure it with worm clamp (realy not that necessary since there is no boost in those pipes, only vacuum.



8) Reinstall the airbox using reverse steps, make sure all clamps are properly secured.

9) You are done, enjoy the subtle woosh the stock DVs can provide (on stock boost that is)

It is probably safe to presume that you would be better off replacing them with forge DVs or BOVs if you want to run higher boost.

[BMW_Alex]

Can we get a quick vid to hear it. Thanks

[mrunella]

Sound clip and video?

[Evochuck]

Done as we speak my jobs parking lot, the sound is ever so slightly louder with some load.

[_ink]

Awesome for those with Forged DV's looking for a change.

[RimasRS]

I cant hear anything... sorry

[Evochuck]

I wasnt realy able to capture de difference on video, but its definitely there....

[COEHSP85]

Thank you for this DIY. Went to my local hardware store, picked up the plugs and removed the bypass hoses from the BOV. It sounds awesome now. Especially combined with un plugging the Exhaust Flap mod.

[StevenY.]

Originally Posted by COEHSP85

Thank you for this DIY. Went to my local hardware store, picked up the plugs and removed the bypass hoses from the BOV. It sounds awesome now. Especially combined with un plugging the Exhaust Flap mod.

Make a video if possible.

[zero2sixtyZ]

Any potential drawbacks to this? Error codes? I'm assuming there is no change to how the DVs operate / wear since this just plugs the reentry for the air.

[Jeffman]

I'm wondering whether there are any measurable performance gains? Maybe the excess boost air pressure can be released more quickly during shifts or throttle off?

[Evochuck]

Originally Posted by zero2sixtyZ

Any potential drawbacks to this? Error codes? I'm assuming there is no change to how the DVs operate / wear since this just plugs the reentry for the air.

No codes will show up, nor performance gains, this is a strictly cosmetic mod.

I'll try to do a better video, its a pain to do with my JB4 WG setting, if I go too fast all you hear is wind on camera, if I go too slow, I cant get proper boost to vent....

[slowbmw]

No measurable performance gains, no codes, only POSSIBLE issue is that the DV valves are designed to work on DP. this means that the little diaphragm that is inside the DV will open based on MAP tube PSI-Charge pipe PSI=Diaphragm opening pressure. If there is no MAP tube pressure this means that the valve may open prematurely or open later than desired.

However, if the diaphragm is only designed based on force pressure (pressure in the charge pipe) then there is no worry at all because the only time the diaphragm flap will open is based on pressure shock...(when pressure is built (turbo spool) there is a small tube or channel that circulates around the diaphragm that presses the diagram closed under boost, and when you rapidly let off of the gas pedal (decrease in force pressure) the remaining pressure in that little channel will act as a low pressure venturi and suck the diaphgram open.

this is similar to how an expansion tank works in a hot water circulation system in a commercial building.

[mex2309]

Is this the same comparable noise you get from installing DCI?

[Evochuck]

Originally Posted by mex2309

Is this the same comparable noise you get from installing DCI?

No, a DCI will give you a louder spooling sound and a tiny blowoff sound, this on the other hand greatly increases the blowoff sound

[zero2sixtyZ]

Did this over the past weekend. Not noticeable unless under decent load, or WOT then shift. Not a bad sound, but I may reverse this based on slowbmw's assessment.

[Evochuck]

Originally Posted by zero2sixtyZ

Did this over the past weekend. Not noticeable unless under decent load, or WOT then shift. Not a bad sound, but I may reverse this based on slowbmw's assessment.

Thats is normal, your BOV will not vent boost unless you are creating some (wich incidently only happens under moderate to heavy load)

[Evochuck]

Still does not do justice to the mod, but still a tiny bit better, id need my gf to film it from the outside to get a proper sound.

[bnd]

Originally Posted by SINasTER

+1

Doesnt seem any louder then stock.

I have both tubes disconnected and can clearly hear the blow off with no problem(under driving load), but thankfully it's not obnoxiously loud. Drive the car in 3rd gear up to 50-60mph and let off the accelerator, you should hear it blow off, if not you probably did this mod wrong. I did this mod to decrease the oil re-circulation more than the sound. You will see a small amount of oil blow off into the engine bay near the tubes, but just clean it up every other week or when you wash the car. Also, may want to point your pipes to an area that's easy to clean up.

In case anyone is wondering, until I could access the rear diverter, I only unhooked the front diverter and the car drove fine/could hear the blow off.

Also wanted to share an option for plugging the intake pipe holes. I used a $3 part from jegs which came in silver, blue or black. Thought the blue looked good... http://www.jegs.com/i/JEGS-Performan...00302/10002/-1 Not sure if this is the exact part size since I threw out the packaging(sorry), but it looks exactly like this. May be the -4AN size...

[BMW-SRT]

Originally Posted by bnd

I have both tubes disconnected and can clearly hear the blow off with no problem(under driving load), but thankfully it's not obnoxiously loud. Drive the car in 3rd gear up to 50-60mph and let off the accelerator, you should hear it blow off, if not you probably did this mod wrong. I did this mod to decrease the oil re-circulation more than the sound. You will see a small amount of oil blow off into the engine bay near the tubes, but just clean it up every other week or when you wash the car. Also, may want to point your pipes to an area that's easy to clean up.

Would it help to put the pipes in a container, empty Gatorade bottle or something, to collect the oil that comes out?

[bnd]

Originally Posted by BMW-SRT

Would it help to put the pipes in a container, empty Gatorade bottle or something, to collect the oil that comes out?

It's more of a vapor spray, not a drip or anything significant(for my car)... I guess you could put something to catch the excess, but a Gatorade bottle sounds a bit ugly for my taste. I'm personally okay with just cleaning it up every so often. IMO, you may want to monitor how much oil is coming out before you do anything and go from there.

Also, I'm installing an oil catch can this weekend, so I'll post back if that reduces the amount of oil spray coming out of the DV hoses.

[shwinturbo]

Here is a pretty good video (sound wise) that i shot of what this exact mod sounds like with a dci and jb4 on map 5