so after ksfrogman said it was a silencer, i thought of making a diy to remove this thing.
So here it is.
Note: this was made with a simota air intake, if you want to know how to remove the oem air intake please see this tread
http://www.e90post.com/forums/showthread.php?t=30688
step 1:
Release all bolts shown in picture 1, and disconnect the air flow sensor.
Step 2:
After you have removed the air filter housing, you need to remove the air intake tube. pull it of in the direction shown in picture 2.
Step 3:
nou you need to cut off the silencer, you can't pull it off because it is glued on to the ait intake tube, cut it off as shown in picture 3.
Step 4:
after you cut off the silencer the you have to put in a plug so it is sealed off airtight, glue the edges off the plug and fit it in to the air intake tube as shown in picture 4 and 5.
after that the tube will look like this:
Step 5:
Now put everything back on the car, like you got it off and then the fun begins.
Results:
my car is now more agressive on the throttle, and the sound is louder and deeper.
EDIT:
Video added:
http://www.youtube.com/watch?v=NJFKERUikFc
Rody