Aftermarket Airfilters - Just a Hype?

**mazdamazda** · December 9th, 2005 11:01 AM

Got this from another thread here:

Originally Posted by jplazo

Before buying a K&N and other overpriced filters, check this out:

http://bobistheoilguy.com/airfilter/airtest1.htm

K&N attempted to counter the findings... but with contradictory statements.

The bottomline is that the stock filter does the BEST filtration and with minimal pressure drop. Branded after markets do lousier filtration with 2 to 8% more airflow.

For stock cars, this sneeze of extra air isn't worth the extra expense.

**zman** · December 9th, 2005 11:27 AM

maybe the one who wrote the article should have specified he was comparing aftermarket "drop-in" airfilters?

**JohnM** · December 9th, 2005 11:42 AM

Buti na lang wala akong pera hehe. K&N drop-in filter: Php 4000++. Paper replacement filter: Php 300.00. That extra sneeze of air will not benefit me because I rarely go above 3k rpm. Besides with the pollution in the city I want to get as much protection as I can.

**ghosthunter** · December 9th, 2005 11:48 AM

It is known that drop-in aftermarket filters do not increase your engine's performance because of the constriction and bends in the stock intake tubing.

Cone-type filters & straight intake tubings will increase an engine's performance.

**mazdamazda** · December 9th, 2005 11:59 AM

I think that what the author is trying to point out is that the filtration capability of aftermarket filters is not up par with OEM filters.

Ergo - sacrificing filtration capability is not worth it for the minimal additional airflow gained.

**JohnM** · December 9th, 2005 12:02 PM

Unless of course you're willing to sacrifice engine longevity for that little extra oomph.

**ghosthunter** · December 9th, 2005 12:05 PM

Originally Posted by mazdamazda

I think that what the author is trying to point out is that the filtration capability of aftermarket filters is not up par with OEM filters.

Ergo - sacrificing filtration capability is not worth it for the minimal additional airflow gained.

personally it depends. I have been using K&N cone-type filters for years with no problems with my cars.

**izzy** · December 9th, 2005 12:17 PM

hmmm.... this is good info... now that i'm planning to install a cone-type filter, i'm having secod thoughts....

will wait for other feedback, though...

**SunTzu** · December 9th, 2005 12:25 PM

better naman talaga ang filtering capability ng OEM air filter kahit k&n or apexi pa icompare yan. sa sobrang restrictive, makakapasok pa ba ang dumi. unlike the aftermarket filters, open talaga surface niya. better for performance lang talaga ang K&N. pero ang point is K&n and apexi are 2 of the best in filtering sa lahat ng aftermarket filters. but of course nothing beats OEM.

**mazdamazda** · December 9th, 2005 12:27 PM

that's why I don't wash my open-type filter (in the 323) that often... AFAIK - dirt in the filter helps in the filtering process.

but for the Rav4, I'm planning to keep it stock (plus with the HUGE air filter needed - I wonder how much would a drop-in K&N filter cost).