K&N Air Filters

It is up to you

I use a K&N standard sized filter (square) on my 300M. I didn't notice anything, but I haven't had to change my filter in 22,000KM.

Steve

Steve - you don't change (replace) K&N filters - you clean and re-oil them.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Hi Bill,

Yes I know, they say to do it every 50,000 or 100,000, I am not sure. I already bought the cleaning kit.

Steve

Ohgawwwwwd, nooooooooooo! Not againnnnnnnnnnn!

If the paper filter can only flow 700CFM and the K&N can flow 900CFM and the engine at full throttle with NO air filter at all can only suck in

500CFM then you have gained nothing.

At Wide Open Throttle (WOT) the engine computer runs the mixture to get it close to ideal mixture ratio as possible that are the easiest for the cat to clean up. If you slightly richen the mixture you will get a power boost because the point of maximum power is different than what the engine computer is programmed for. But there will be more pollutants for the cat to clean up. Too rich and the cat can get sooted up so the street versions of these chips only make very slight modifications, which are probably only measureable on a dyno that is running repeated tests that are exactly the same. Almost certainly not measurable by seat of the pants. Your benefits for this are a big loss of fuel economy, of course.

If you put a radical cam in the engine you will increase power and then new engine computer programming is called for. That can develop noticeable by seat-of-the-pants increases. But if your not changing anything else, a new engine computer chip is a feel-good thing only.

Ted

I just bought a pair of K&N filters for my Crossfire, but the decision was based purely on economics. The stock air filters are $32 each at the dealer or $64 to replace the pair (the car has two air filters in the air box). I found the K&N filters for the car for $30 each. Add another $14 for the cleaning kit and the first replacement was $74. However, since you clean the filters instead of replacing them, I will be ahead in another 15K when they should be replaced a second time.

The K&N filter-equipped cars that post UOA's on bobistheoilguy.com tend to show increased silicon levels, indicating poor air filtering. Use at your own risk.

bob

The website does not work, do you have a good link?

Steve

Exactly right. These filters pass more air than the motor can use and pull this off by providing less filtering than the paper OEM filter which, itself, lets pass more than enough clean air through to meet the most demanding draw by the motor. It's kind of like selling someone the Brooklyn Bridge. The trick would be developing a reasonably priced filter that filtered better while letting in at least as much air as the OEM filter in a smaller space to make room for more stuff under the hood. Good luck finding that product.

Richard.

Had to know.

What about chips?

Thanks for the education. I will leave things as they are. If I really need more power, I guess I can always upgrade to the 300, Charger or Magnum. It's just that I really like the style of this car.

Oh, well. You can't have everything.

for your reply.

I will keep things as is. As I mentioned to another poster, I guess I can always upgrade to the 300, Charger or Magnum with the HEMI. It's just that I like the styling of this vehicle so much.

Ken

Do you realize that you never once told us the vehicle that you have?

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

NJ Vike wrote:

Didn't realize that. 2002 300M

Ken

That's why I asked.

Do a search on "Kenne Bell" on the 300M Club forums (club:

forums: There are people there, including the track recordholder for normally-aspirated M's, that are getting some benefits out of their product - it is the only one that gets positive comments. If I'm not mistaken, it's not really a chip that they produce - they re-program your existing chip. (Be patient with the forums - they are having server problems lately. If the above links don't work, try them without the '.100megs42')

Bill Putney (To reply by e-mail, replace the last letter of the alphabet > Didn't realize that. 2002 300M

ran a test between an AC Delco air filter to a Kool Blue drop-in panel filter, and a K&N drop-in panel filter on a 1996 Cadillac Seville STS. His conclusion was "The AC Delco paper filter gave the best results. The margin of the 0-60 results are within the error margin of the test, but to be fair the paper filter won the 0-60, 0-80, and best HP showing. It ran

3rd of 5 runs, so had no place advantages. "

In another test,

found "The stock filter will flow MORE THAN ENOUGH AIR to give you ALL THE HORSEPOWER the engine has to give. And this remains true until the filter is dirty enough to trip the air filter life indicator. At that point performance will decline somewhat. Replace the filter and get on with it." (Test was on a GM Duramax Diesel.) If you look carefully at the "total dirt passed" chart, you will see that the K&N was one of the worst performers. I read in another forum that, that's because it was designed for racing and the concern is not for filtering ability (race engines are torn down frequently) rather it's free airflow. (It does have the least restriction indicating that its filtering media may indeed lean towards letting teh air get through trapping only the largest particles and is not the best for street conditions.)

In a test presented on

they found that the K&N did not filter better (worse actually.) In all the research I've looked into on this, I was unable to find a single place where the K&N actually filtered better. I came to the conclusion (for better or worse) that it was not worth the money and did not filter better than an OEM paper filter (which seemed to work better in all cases, other than getting wet.) In my opinion, AC Delco and Motorcraft are good choices. Avoid Fram (oil or air) at all costs.

Bill,

Thanks for the link. I remember seeing this site several years ago and was going to join. I should have remembered but I noticed the URL has changed.

Also, it appears that someone else is running this, true?

I really like this person's M:

Thanks for the response. I'm going to leave things as is.