What is the assessment of the engine air filters that are on the market for the Smart

Jeff C. · 10-25-2009, 11:58 AM

I have done a search of the existing information on this site on air filters.I entered "air filter" as the search topic.There was a lot of enteries that came up.If fact there were twenty screens or pages that were available to draw from.The most striking responces involved K&N,Breathless Performance Products and AFE.I was extremely interested in the K&N 33-2417 initially.However as I continued uncovering past posts,I encounted information as to a negative theoretical outcome involving the fear of doing unnecessary damage to the rings in the engine.While I am not a tech-savy type of person,I understand that the argument made was that air filters that allow more air into the engine do so by essentially NOT filtering as well the particulate component of air that passes through the filter.My presumption is that a person would probably want an air filter that actually filters the air that the engine would be using and that the better that the filter could do the job of filtering would be the otimal thing to strive for.What is thought to be reguarded as the standard to look for in air filters?Is this possible damage that rings would suffer an actual or theoretic concern for a car that is driven on the streets as opposed to what is seen in off road bikes(this is the argument that I found on the boards)?Are paper filters a better solution to the problem than filters that allow more diffussion?
I can tell that this is going to encourage A LOT of debate .At least that is what I am hoping for in an attempt to flush out as much commentary as possible in getting to the information that allows those of us who are not tech-savy to benefit from.

johnjohn · 10-25-2009, 12:06 PM

I have used k & n filters on quite a few vehicles,I have one on my 1994 mazda b2300 truck, It now has 211,000 miles on it.
I installed a k & n filter on my smart as soon as the correct part # was available.
NO OTER MODS DONE. Stock intake, just k & n filter.I now have 25,000 miles on my smart, I still love the thing.

**jwight** · 10-25-2009, 12:46 PM

Just my .02; have tried all three and currently have the aFe filter installed. In reality probably not much hp gain, if any. Car does feel a little quicker and has a nicer (IMHO) sound to it compared with stock.

Heard a presentation from a Corvette engineer several years ago addressing aftermarket intakes - they'd tried them all and found little difference between the OEM intake and aftermarket setups. Their OEM airbox and filter was designed to balance cost, noise and filtering effectiveness where the aftermarket filters and intake systems can ignore all three if they wish. YMMV.

jefferios · 10-25-2009, 01:06 PM

I am interested in getting one of the aftermarket filters too, but I don't know which one to get. I'll looking forward to what people have to say.

NeWave · 10-25-2009, 01:12 PM

As you know, I have one as well. They're in all my cars. Not filtering well is a bunch of rubbish. K&N has a million mile warranty.. and will replace your engine if their filter is the cause of it's failure. It breathes better, hence better response and mileage. Filtering is not sacraficed. my brother has had the same one on his car since new. 275,000 miles. Original engine. I'll let you drive mine if you want to see the difference...

sunnyokanagan · 10-25-2009, 01:22 PM

The OEM paper filter is fine. Just be sure to swap it at every oil change or every 5,000 miles, whichever comes first.

If that's too much bother, or if you have done performance mods to the engine that will benefit from more intake volume, upgrade to an oiled cotton filter like the K&N. Just be sure to keep it cleaned and carefully oiled for proper filtration.

For high-performance air, step up another notch to a tri-foam racing filter like the ITG.

B

chumly · 10-25-2009, 02:07 PM

I've used k&n filters on almost every vehicle I've owned for the last 30+ yrs and never had any problem related to the filter.I've used a similar type of filter (same but different make) and never had a problem. I would definitely advise you to get one if for no other reason, it will save you money in the long run(cleaning and reoiling vs replacing).If not k&n even the oddball brands are better than paper IMHO.

WhiteNBlack08 · 10-25-2009, 04:26 PM

I've had a K&N in my smart since about 3000 miles(when the K&N's became available). I noticed about 2 mpg better mileage with mine. I have K&N's in both my vehicles, and the one in my truck has 75K on it, no issues. My smart now has 39K, no issues there either.

There will always be debate on what is better for the engine, but K&N does offer a million mile warranty, good enough for me!

TMACK · 10-25-2009, 04:34 PM

I use K&N filters on my Smart, Mini Cooper, Buick Regal and Ford F-150.
I've used K&N filters on my Jeep Cherokee and Wrangler, and Saturn.

No complaints, no technical problems, better performance.

**rfernatt** · 10-25-2009, 04:36 PM

I have the AFE oiled filter as well and have been using it for about 12K miles. Not much difference that you can tell. MAYBE a bit better MPG and sound, but it is a subtle difference. I don't think anyone has been using these filters in the smart long enough to make any informed statement about abnormal smart engine wear due to poor filtering ability, but experience in other vehicles leads me to believe it to be a non-issue. However, I have decided to keep changing my oil at 7,500 mile intervals.