or will there be no performance gain whatsoever? is it a pure waste of money?

 

spending $20 every 20-30k miles or spending $50(one-time) for a reusable filter...i'd rather spend $50 and not have to worry about it....

performance gains i think are nill....unless someone has a dyno of the stock air-filter to a k&n drop-in filter....

 

I had a K&N on my last car. It was noticible when I first installed it (but that could be because the one it replaced was dirty.) The claim was 5-10hp.

HOWEVER...

I had a MAF sensor go out, and the service tech claimed it was caused by oil from the filter (after months of trying to diagnose why my car was cutting out). They didn't want to cover it under warranty because they claimed that I caused the damage with the aftermarket filter. It was eventually sorted out, but the headache wasn't worth it. I'll just stick to the regular ol' (non-oiled) filters.

 

I'm using the K&N drop-in in my TSX. I didn't notice much difference in performance. Then again, I only drove the car about 10 times before I changed the filter and I'm not the kind who can tell the difference between a few hp.

I like the "reusable" aspect of it.

 

Truth be told I really didn't notice a performance difference attributable to the K&N filter. I swapped the filter and the Icebox lid at the same time. BTW, you can pick the filter up at Autoanything.com for a bit less. Keep in mind that you also need to buy a service/recharge kit which is good for 7 uses.

 

Personally, I wouldn't put in a K&N filter on a $30k car.
Warranty issues, *possible* engine damage, etc.

On my $2k beater, sure why not but I'm not risking it on a new car.

 

Well, just the filter alone won't get you any gains really. But if you remove your resonator and then drop in a K&N, you will notice a little gain. Gettting a CAI, is ultimately the best way to go. I have not one regret with mine.

 

I've had them in a few cars and also in my '04 TSX. I had one in a 125hp car that would dip (-100rpm) in RPM when the AC turned on before the K&N and didn't after I installed it. That got my attention.

It did help on the inherit hesitation problem in the TSX. I did drive the car long enough to have a mental baseline as to how it was pre & post the K&N air filter. As to the question of the oil, you are not supposed to have any excess oil where it could drip, etc. You will see a slight drop in your city MPG range. I'm not one to WOT in town but I ALWAYS seem to leave everyone in my rear view mirror at the green light. After I hit 10mph I'm gone with very little feeling of the engine holding back. I think anytime you can make your intake less restricive - do it. Unless your are going to change out some of the hardware I say for $50 or less... do it.

 

I just run FRAM or Champs Air Filters in my car and change them every 30-50,000 miles. I think the majority of the air filters that are replaced today are totally unnecessary.

Air Filters last a LONG time on paved roads. Few people understand; in order for an air filter to work well, it must load up with dirt (lightly) to reduce some of the air flow. Of course, if its caked with dirt, its going to reduce your fuel-efficiency, so the trick is to find the right balance.

From past experience, 30-50K is reasonable for a paper air filter.

 

30-50k???? wow, i changed my OEM TSX filter at 10,000 miles lol

 

Look at the flow characteristics and filtering of the K&N compared to paper media filters at www.bobistheoilguy.com. I think you might be surprised.

 

You live in SoCal??? I don't recall SoCal being that dusty...

Again, an air filter must actually load up with dirt to reduce some of the airflow before being able to filter well.

fwiw, Ford has been using a very large oiled filter element in their Focus since 2003. These units are not mounted in the engine compartment. They are technically considered a lifetime Air Filter, and SAE tests have shown that these units are capable of 150-200K under most conditions. Oh yes, and its $180 to replace it...

 

Does that make it a CAI?

 

An amsoil filter is much better. If you hold a new K&N filter up towards the sun. You can see holes that the light gets through. The amsoil one is a foam filter. Plus when i had a 4runner, i knew this guy that actually did dynos and the amsoil won by far. The K&N actually decreased HP. If you overoil the filter you will get the MAF messed up. What you need to do after applying oil liberally is take 6 paper towels on the top and bottom and then step all over the filter. That will get the excess out and will keep your MAF from getting messed up.

If you want to read about the dynos.
http://www.gadgetonline.com/AirInduction.htm

This guy knows his stuff too. He does all of his own tests.

 

Im sticking with the stock paper filter on my car. just not worth the risk.

I had an oiled/cotton filter on my DSM for flow but with the MAS sensor all the way up near the throttle body, it was in no harm of getting oil fouled. (Turbo and IC were in the way.)

 

i have a K&N filter in the TSX.