[JingChai]

I was planning to do a charcoal delete but realized that most people go with the K&N filter.

I have the stock filter from BMW: https://www.ecstuning.com/b-genuine-...r/13717542294/

Would the charcoal delete not be recommended with the stock filter?

[CTinline-six]

You don't need to put in a high flow filter. Stock filter will work fine.

[nsjames]

I did it and ran it with the stock filter for a while.

although I'm still not really sure if deleting it actually does anything.

[Biginboca]

Yes it’s worthwhile. Any restriction you lose helps...

https://www.e90post.com/forums/showthread.php?t=1584439

[JingChai]

I did the charcoal delete this morning and did a test drive, heard a louder noise coming into the engine and accelerated a bit faster.

Definitely worthwhile to do!

[Mkze90]

I did my a week a go, it definitely sounds louder when you mash the pedal. Other then that i didn't notice any gains, but damn that filter was nasty.

[shuotong]

It is louder, although possibly no gains if you don’t tune the car to use the less restrictive air box. I’m running Mann air filter, would not suggest the k&n filter because the gain is minimal while the filtering performance is certainly not as good as stock paper.
I get a European air box though, along with a K&N air filter because the seller just can’t be bothered by selling it separately. Would be interested to see if I can swap the filter for track days because it’s very easy to change the filter in EU box, and there is actually ~3kw gain from the kn filter.

[hassmaschine]

You don't need to tune the car for an air filter. lol.

Deleting the carbon filter is already Dyno proven many times over.

[gamesfrager]

I just did this exact mod. Delete the charcole filter and installed new MANN / stock filter.

I did notice right away smoothness / responsiveness at lower RPM. I have trip coming up soon so will see how that feels / sounds at 100 - 120 km/h

[Ricthewrench]

Got my first bmw. Loving it. Charcoal delete coming up, I love a sweet motor gulping air! R

[Aim2Game]

Does the charcoal filter not serve a purpose to keep charcoal out of the engine? Can someone please explain what the reason BMW put it for in the first place is ?

[gamesfrager]

Originally Posted by Aim2Game

Does the charcoal filter not serve a purpose to keep charcoal out of the engine? Can someone please explain what the reason BMW put it for in the first place is ?

Because our cars can get hungry and start swallowing charcole.
And end up with a steampunk car.


Charcole filter because the filter itself contains charcole. It's not filtering out charcole.
The reason BMW put it is to meet emissions regulation. Supposed to help reduce fumes coming out through the intake.

It helps slightly making the car breath better when removed. Imagine trying to breath with a towel on your face.

[Aim2Game]

Originally Posted by gamesfrager

Because our cars can get hungry and start swallowing charcole.
And end up with a steampunk car.

Thanks gamesfragger, I get what you mean and will be doing the charcoal delete this evening

[gamesfrager]

Originally Posted by Aim2Game

Thanks gamesfragger, I get what you mean and will be doing the charcoal delete this evening

Nice. There are a couple of videos on youtube.
Make sure you clean up the cut area very well.
And post back if you feel any difference.

[Machspeed93]

Wouldn't having less air filtration be bad for the engine in the long run?

[Machspeed93]

Originally Posted by freedomfries

The charcoal filter's purpose is to absorb fuel vapours from escaping your engine into the environment. I believe it was added to achieve a certain emissions classification

I thought it had to do with the stock filter having charcoal in it so it would catch those particles?

Stock filter + charcoal filter = clean air but more restrictive

KN filter + charcoal delete = less filtered air but less restrictive

Stock filter + charcoal delete = less filtered air, less restrictive, but some added charcoal particles from the stock filter??

I could have sworn I read that the stock filters have some charcoal in them. Is the slightly dirtier air in the engine even a big deal for a port injection engine?

[The Nightman]

Are you thinking of the cabin filter? They have charcoal to help absorb odours

[nsjames]

Originally Posted by Machspeed93

I thought it had to do with the stock filter having charcoal in it so it would catch those particles?

Stock filter + charcoal filter = clean air but more restrictive

KN filter + charcoal delete = less filtered air but less restrictive

Stock filter + charcoal delete = less filtered air, less restrictive, but some added charcoal particles from the stock filter??

I could have sworn I read that the stock filters have some charcoal in them. Is the slightly dirtier air in the engine even a big deal for a port injection engine?

there is no filtration value in the stock charcoal intake filter.
I could see through it.
Everything is absolutely filtered through the actual engine air filter. Down to whatever particle size BMW specced.
If the charcoal actually caught any contaminants it would eventually plug, as it is not replaceable.

there is no charcoal in the factory paper air filter.

[Bufalo]

Charcoal filter is an emissions control device to prevent gasoline fumes from EXITING through the intake system into the atmosphere when the vehicle is turned off.