K&N test - suprising

Looks like any of the filters will do a fine job at keeping most of the dirt from the inside of your engine.... I wonder which ones flow the best??? Just for the record K&N says their filters catch far more dirt after they are used for a while and have some dirt built up on them...without reducing flow. TG

I personally like a filter that does a very good job from day one so my engine doesn't suffer while the dirt is building up on the filter. Why would I settle for anything less? Just get a OEM or Purolator and change it every

It's an interesting article, but it didn't cause me to have any doubts about using the K&N. I didn't buy it for increased performance or filtering, I bought it because it can be cleaned and reused.

Andy

I'm no fluid dynamicist, but I've a feeling that filters that flow better also let larger (dirt) particles through.

Seems like a false economy if your car loses thousands of miles off its 'lifespan' and ends up going to the auto 'recyling center' before it may have with diligent use of a better filter. If you didn't buy it for its filtering, why run one at all? When you clean it, what's going down the drain? On your yard? Over the fence into your neighbor's yard when he's gone?(kidding!)

Carl

Andy Mas> It's an interesting article, but it didn't cause me to have any doubts about

Amsoil has recently change the air filter and is now called Flowzair. Amsoil gives you the source of their test procedure. Amsoil performance conclusion: SAE J726 (iso 5011)

1. averaged 18% greater airflow
2. up to 99.5% cumulative efficiency
3. generates 1.5 to 4.4 time greater dirt-stopping and dirt-holding filter capacity.

I recently checked out a K&N box and just stated a independent lab compared filters and gave no source of testing.

If you're assuming the same surface area for air to get in, yeah, it would pretty much have to. If they can get a larger surface area, they can get more air in with the same size "holes".

Not necessarily. That can be quantified, and is referred to as filter efficiency: The ratio of resistance to air flow to (inverse) particle size allowed thru. If what you are saying is true, efficiency of all filters would be identical, and that is not the case. However, generally what you said is true. A premium filter should have higher efficiency if it's truly a "better" filter.

And, since a K&N filters filter better as it accumulates dirt, the resistance to air flow is probably (certainly) increasing at the same time - which I think was your point.

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

Fair play to Bob for actually testing the filters out in the first place but

I have a Framulator in it now (not nearly as sturdy as OEM, btw), and am discouraged with the MPG. I had a Mazda Protegé and added a cone filter, and improved my mpg by ~12% and I was already getting 31mpg in and around town. I'd like to do the same for my '02 Legacy GT, but there are few that can filter dirt to the satisfaction of the intake sensors (K&N, Cobb...?). And as I don't want to spend the $ on a complete intake system when the car only has 23k on it, I'll try the K&N. if it doesn't work, I'll go with Subie-filters til I get the tinkering itch in the Spring! then maybe a Cobb CAI system. Terry - '03 Silver Legacy SE sedan - 36 miles! '02 Regatta-Red GT wagon 5spd - 23k miles Yakima / TandeMover / Rockymount rack To reply, get rid of the "nonsense"

Got my K&N today - let you know how it goes... I hope to improve the mpg. Terry - '03 Silver Legacy SE sedan - 36 miles! '02 Regatta-Red GT wagon 5spd - 23k miles Yakima / TandeMover / Rockymount rack To reply, get rid of the "nonsense"