K&N Filters
06-24-2010, 08:05 AM
#11
Members
Join Date: Jan 2009
Location: West New York, NJ
Posts: 34
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2006 525xi-Stock
I have a 525xi, and I noticed that there is a smaller charcoal filter after the regular air filter. Can that be removed? It seems like it would restrict a lot of airflow.
06-24-2010, 08:09 AM
#12
Senior Members
Join Date: Jan 2007
Location: USA
Posts: 471
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: Car
06-24-2010, 08:16 AM
#13
Members
Join Date: Jun 2010
Location: DFW Area
Posts: 115
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2011 Lexus IS-F
the k&n will for sure let larger particles through. you can check their website, i think they'll pass particles as large as 10-25 microns, stock filter will likely limit size to 5 microns. bottom line is that if the filter has less flow resistance then it must have more open area. just plain old fluid mechanics at work here. i use them on my bikes b/c a new engine for a bike doesn't cost 10-20k like it would for my 545i. plus the hp gain in the car due to the filter are so small its not even worth the risk.
06-26-2010, 10:00 AM
#14
Members
Join Date: Nov 2007
Location: Houston, TX
Posts: 178
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 07 550i Titanium Silver, Black Dakota Leather, Steptronic, Sport, Premium, Nav, Sat. Radio, Logic 7, Comfort Access, Rear Sunshade.
Thats true. Do a test by getting a white cloth and swab after the filter in the intake and see if the cloth still stays white. I bet you'll be surprised. You have to have some miles with it to show, dont expect 100 miles to really show anything, but with 10k or more you'll see. Another common problem with oiled filters is that people tend to over oil them and mess their maf sensors up too. The vehicle these days have better designed air intakes and all that you may experience is a 1 hp gain if that.
06-26-2010, 11:07 AM
#15
Former Vendor
Join Date: Oct 2006
Location: Anaheim, CA
Posts: 19,460
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: F13 M6
06-26-2010, 11:07 AM
#16
Members
Join Date: Nov 2009
Posts: 123
Likes: 0
Received 0 Likes
on
0 Posts
As you may suspect the charcoal filter is not really necessary for the car but just polar bears.
06-26-2010, 11:08 AM
#17
Contributors
Join Date: Jan 2009
Location: Fort Lauderdale, FL
Posts: 645
Likes: 0
Received 0 Likes
on
0 Posts
My Ride: 2006 550i | Silver-Grey- A08 | Premium - Sport Package | Adaptive Headlights | Logic 7 w/ CD Changer | Bluetooth | Park Distance Control | Xenon Headlights | Comfort Access [s]Sprint Booster V1[/s] | K&N filter - Stock Box w/ Charcoal Filter Removed | Clear Side LED Markers | Matte Black Grilles | RPI Air Scoop | RPI 550i GT Exhaust | 12" Kicker w/ AMP | Headlight Euro Overlays | ACS Rep Roof\Trunk Spoilers |MTEC V2 Angel Eyes | 6000k HID Fog Lights | 19" VMR v710 Stag Wheels | Hankook Ventus V12 Evo K110 Tires | Debadged | LED Courtesy Door Lamps | Sprint Booster V2 | Painted Calipers | M pedals\shift knob | HID License Plate Bulbs | R1 Drilled\Slotted Rotors | Hawk HPS Brakes| ACS replica front lip |
RPI scoop installed, K&N installed and Charcoal filter removed.
Thread
Thread Starter
Forum
Replies
Last Post