K&N replacement intake filter for E9x

[DARK_M3]

I'm considering getting this. I have always been a fan of K&N filters. Thoughts?

[Keik E92 M3]

I did mine last night...

[Singletrack]

Originally Posted by dark_knight

I'm considering getting this. I have always been a fan of K&N filters. Thoughts?

You will probably lose 1% filtration (98%) and gain 1% horsepower...

I like the Macht Schnell filter personally since they meet the same filtration standard as the OEM filter - ISO 5011 - 99%.

Can't find a link to their test data anywhere though...

Looks like the K&N is stupid close to that at 98.69% (once it has collected some dust to filter properly)

http://www.knfilters.com/dynocharts/E-2994.pdf

...other comparable options out there also if you search.

[DARK_M3]

Originally Posted by Singletrack

You will probably lose 1% filtration (98%) and gain 1% horsepower...

I like the Macht Schnell filter personally since they meet the same filtration standard as the OEM filter - ISO 5011 - 99%.

Can't find a link to their test data anywhere though...

Looks like the K&N is stupid close to that at 98.69% (once it has collected some dust to filter properly)

http://www.knfilters.com/dynocharts/E-2994.pdf

...other comparable options out there also if you search.

Helpful. Thank you. Yeah that's stupid close. Then again, $70 for 1% hp... hmmm. Perhaps just scrap the idea.

[Singletrack]

Originally Posted by dark_knight

Helpful. Thank you. Yeah that's stupid close. Then again, $70 for 1% hp... hmmm. Perhaps just scrap the idea.

If your car is really a 2008, then it has a charcoal liner in the filter. You can confirm by opening the box. If it is white with orange trim then it has it. If you have this filter, it is very restrictive. So it is well worth replacing it. The later M3s came with the same filter as the Euro model; which did not include a charcoal lining and flows much better.

So old filter - definitely upgrade. New filter - up to you, but there should still be some minor gains.

[DARK_M3]

Originally Posted by Singletrack

If your car is really a 2008, then it has a charcoal liner in the filter. You can confirm by opening the box. If it is white with orange trim then it has it. If you have this filter, it is very restrictive. So it is well worth replacing it. The later M3s came with the same filter as the Euro model; which did not include a charcoal lining and flows much better.

So old filter - definitely upgrade. New filter - up to you, but there should still be some minor gains.

Sounds good. I will check it out tomorrow. I guess $70 isn't a bad investment for the return now that I think about it.

[crabman]

Dont forget the sound. Depending on your opinion of induction noise a filter could be worth it or not on sound merits alone. As I read it the old charcoal filters gain (depending on reports) a fair bit of induction roar. The newer sans charcoal liner filters gain a little but not so much. I like induction sound as I grew up with it back when most cars had open element filters so this is a no brainer for me considering the cheap buy in. For you it might be wasted money?

[M3PO]

I have the K&N filter and I have no complaints. I got it for nearly half (~$55 IIRC) of the MS filter from Amazon. I ran the same K&N filter on my 350Z for five years and all of my oil analyses showed low silicates meaning good filtration.

I do have to say that at certain RPMs (~3k or so), the induction noise isn't too pleasant. It sounds almost as if the filter is vibrating against the side of the box. I don't think that it is and I don't think this is unique to K&N.

[Wendall]

I had the 08 Carbon lined filter and installed the AA green filter and it was a noticeable upgrade and the noise is much better.

[mark896]

I went with an AA Green filter and haven't looked back. If for no other reason, it's cheaper maintenance since the filters are supposed to last forever. There is no annoying intake noise at any RPM that I can notice. Tiny bit louder, which I like.

[italyix]

Originally Posted by biggynuts01

I had the 08 Carbon lined filter and installed the AA green filter and it was a noticeable upgrade and the noise is much better.

This this as well. Slight butt dyno gains as well.

[2000gsr]

Does MS sell a recharger kit? Or do they expect you to use K&N charger kit?

[Kyoshi71]

I personally think the quality of K&N has dropped in recent years and would not install one in my car. AA is by far my favorite drop-in.

However, K&N's re-charge kit is the best. The detergent is powerful and the oil is aerosol so it goes on very evenly.

[M3SQRD]

^This. AA's green filter is the way to go!

[m3an]

Originally Posted by Kyoshi71

I personally think the quality of K&N has dropped in recent years and would not install one in my car. AA is by far my favorite drop-in.

However, K&N's re-charge kit is the best. The detergent is powerful and the oil is aerosol so it goes on very evenly.

o really??? where did you come up with that?? And how long has AA been making filters?? Do they stand behind it with a warranty card?? C'mon, nothing wrong with a good K&N

[m3an]

Originally Posted by dbarnes

^This. AA's green filter is the way to go!

both you guys have any reason to back up your speculation as to why K&N isn't good??

[M3SQRD]

Originally Posted by talontid

both you guys have any reason to back up your speculation as to why K&N isn't good??

I have no scientific data. However, I have used the K&N, aFe and AA drop-in filters. Based on build quality and pleat design (in particular amount of bleed on the ends of the pleats) I'd rate them in this order - AA, aFe, and K&N. Also, based on induction noise the AA and aFe have more induction noise and sound similar whereas the K&N didn't sound much different from stock ('09 with charcoal filter).

[Singletrack]

Originally Posted by 2000gsr

Does MS sell a recharger kit? Or do they expect you to use K&N charger kit?

Yah they have one. I bought it, but have not used it yet. I believe it includes a cleaner and an oil spray bottle.

[Sean@PYSpeed.com]

There's always a BMC filter!

[DARK_M3]

Originally Posted by Sean@PYSpeed.com

There's always a BMW filter!

lol... please elaborate!

I still have a K&N charger kit from my Stillen Gen III intakes on my 370z (which use two K&N filters) so I think that'll cover whichever way I go.

I definitely like the idea of a more aggressive sound but at the end of the day I want the most hp gains possible and clean oil.

[Kyoshi71]

Originally Posted by talontid

o really??? where did you come up with that?? And how long has AA been making filters?? Do they stand behind it with a warranty card?? C'mon, nothing wrong with a good K&N

AA re-boxes Green brand filters which are excellent quality.
Green was formed when Yellow filtration merged with the Blue Filter Company.





(...and if you believe that....holy shit!)

[kmarei]

Originally Posted by Kyoshi71

Green was formed when Yellow filtration merged with the Blue Filter Company.





(...and if you believe that....holy shit!)

That's totall BS!
The Blue Filter Company bought out the yellow filtration company
Anyone that tells you it was a merger is lying!
I know, because I had a majority stake in the Yellow Filtration company