i am considering one for 2005 Forester ... are these air filters worth the money?
- posted
16 years ago
i am considering one for 2005 Forester ... are these air filters worth the money?
Has anyone actually compared the filtration area, effectiveness, etc on these air filters?
I know of > i am considering one for 2005 Forester ... are these air filters worth the > money?
Well, after asking my question decided to surf the web and found one test made by someone that understands what all of it is about.
Good Luck!
coaster wrote:
Hi, I use foam filter impregnated with oil. Wash it every two years. When I see all the fine dirt the filter caught, I know it's doing the job. Wash, clean it, spray very very thin layer of oil, wipe off excess put it back, use it over and over. My reason is economy rather than using throw away type paper filter. I don't race.
Hi,
I haven't used the K&N--did use an Amsoil "oiled foam" model years ago. Next door neighbor installed a complete K&N intake system on a Mazda Miata earlier this year.
His comments:
--Don't expect huge increases in power or fuel economy. The most noticeable savings will most likely come from NOT throwing away a paper unit a couple of times a year.
--With the complete intake system, the overall noise level in the engine compartment increased. A lot!
--Some aftermarket parts require emissions testing and approval from a regulatory agency to be "legal" for street use. If there's an underhood sticker in the package w/ an "emissions approval" seal or number (CARB number here in California, or anything apropos to your locality), be sure to install it. The fellow who did his last smog test told him he was fine, as he'd installed the sticker K&N sent in the kit. W/o it, the car would fail the "visual" part of the test because of "non-factory" modification. I dunno about other localities and their practices. Just installing the filter w/o any other mods shouldn't be problematic in this department.
Rick
I've had one, and found it to be too much work. I am also concerned about oil and the MAF sensor; K&N says no problem, TSB's say otherwise. I will stick to paper. I did find this test and learned a lot about filters. The graphics take a bit to get loaded.
what oil do you spray on the filter? is this after you washed with water? thanks!
Those willing to the work may save a few bucks over the long run, but it is a lot of work.
Performance wise?
Looking at K&N's own graphs, most foam filter gains are at very high RPM's, ~ 5000 RPM, nowhere near the 1500-3000 RPMs that most cars see in normal driving. Even up the high range, the gains are at most a few horses and not something all that noticeable.
On K&N's own published FAQ, they no longer claim a mileage increase, only that "some customers have reported gains". I'd bet those folks went from a dirty paper filter to a clean K&N. Similar gas mileage gains probably would have been seen with a clean paper filter. I think is was last year that the gov't clamped down on unsubstantiated mileage claims in advertising.
On a fully prepared race car, with all kinds of mods that add a few HP each, they all add up, so a K&N is probably useful. On a street car, the biggest K&N performance gain will probably be from the decal or the visual impact under the hood of a show car.
Very true.. Reading the perfornance charts on the link I posted, about how much dirt can get through scares me. I don't rebuild my engine after each race... oops most of us dont race! Steve
Hi, The filter came with a spray can of oil. I think K&N has it too. Yes I wash it in warm water.
BTW, this filter kit is from Amsoil. The trick is using oil very little. If it goes thru foam, there is a risk it can screw up MAP sensor. I wash filter in summer time and dry it well under hot sun, then spray oil very thinly on the foam intake side. Squeeze it between newspaper sheets to soak up any excess oil. Need to do this every other year for normal driving. Using this since car was new and did not have any trouble.
Winter bar chain oil (chain saw)) works good for air filters. Nice and sticky. You don't need much.
The difference is the change in engines. Years ago, with carbs and first generation EFI, a blocked filter made the engine run progressively richer as it plugged up.
With OBD2, in particular, this is no longer the case. The computer adjusts the fuel to the amount of air available, keeping the mixture more or less constant - so on today's engines a free flowing filter does NOT affect fuel mileage. It CAN affect power output, but generally only at high RPM when the engine air demand exceeds the capability of the filter to supply it.
We can debate performance gains but the cost savings of cleaning make it worthwhile
Ditto!
No arguement there. Had one on my first Aerostar - moved it to my second Aerostar. Olso one on my daughter's Neon.
Likely saved over $200 over and above the cost on the two Aerostars (about 400,000km betweeen them) and another 100 or more on the Neon
I agree on the OBD tuning, but disagree on the cost savings. I feel, and is supported by the web page I posted, that the k&n lets too much dirt through. You may save money in the filters, but think it isn't worth it to the life of the engine.
Hi, OBD tuning? Doesn't OBD mean on board diagnostics? What does it have anything to do with tuning? When trouble occurs, ECU puts the engine in default mode(limp mode) at least to get you moving with CEL on. ECU has a limit, any filter has a limit. Even HEPA filter is not 100%. I am sure reusable filter is economical for long run. It's matter of how to use it. I never heard K&N filter caused engine damage. Did you? Way back, oil bath filter was very common. Some even used toilet paper roll in lieu of regular paper filter. In over 50 years driving I never suffered an engine damage due to poor maintenance. I always keep my vehicles in original condition. My rule of thumb to replace a car. When it starts leaking oil. It happens when the car is around 10 years old. I donate it to Kidney foundation, then go out buy new one with cash saved over during that 10 years.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.