I see that many of you are not members of the K & N fan club. I have to admit that I had one of the flat filters and did not really like it. Is that the one everyone hates or is it K & N altogether? I think they have been making the cone style as long as anyone and I know from my younger days, they were well thought of for drag racers and off roaders. I have not had any problems so far but it's only been on a few weeks. I am just wondering if I need to find another filter for the intake.

Thanks,
John
03 7.3l, CC, 4x4 dually, 6 spd, K & N FIPK intake, Superchips Max Micro Tuner, 91 gallon transfer tank/toolbox combo, Muffler delete

 

Lots of people LOVE the NAPA 6637 filter. I currently have an AIS but my 6637s will be here Monday and I'll be trying them out. Strokin'-It and others have oil analyses that show the 6637 doing as good as the OEM setup, so I'll feel safe running one. It's "louder" e.g. you hear more turbo whistle and intake drone. I do 30,000miles+ annually so we'll see if the added noise of the 6637 is too much for me. Kwikkordead went to AIS from the noise, but that's always going to be a personal choice.

Here are some thread links for you to read more about the 6637:

https://www.ford-trucks.com/forums/5...s-h-u-g-e.html

https://www.ford-trucks.com/forums/5...led-today.html

https://www.ford-trucks.com/forums/5...eally-big.html

And one of the best links to should bookmark:

http://www.7point3.com/mods.aspx

 

The K&N FIPK is better than the drop in box filter replacment from K&N. However, it's still the same type of material, just a larger filter surface. So it does filter better than the drop in style, but still not as good as the others.

 

With the same material, the FIPK will not filter any better than the drop-in filter. Larger area just means more air flow, but it will still pass dirt particles
the same size....

 

I am not a fan of a filter I can see plain sun light thru because of the larger viods in the cotton material. this was from a nearly new filter. I am also not a fan of washing and waiting for my filter to dry while my truck sits in the driveway. I have personally seen 2 powerstrokes destroyed becuase of the drop in K+N's. all that to say that there on some on this board that have run then for a long time with dust hurting the turbo or the motor but it is my strong opinion that there are much better filtering options out there for diesel engines. I use the full Tymar which uses the same filter as the kwik filter or the napa 6637. its a very large paper filter that is pretty inexpensive and in my case last a long time. $25 dollar filter that lasted well over 30,000 miles then sold the truck and removed for my next truck. which came with yet another 6637 so I haven't installed mine yet.