Re: bmw-digest V9 #1004

["Allan Williams" <allanw@xxxxxxxxxx>]

The cone by itself is *usually* a waste of time, because it sucks in hot air
from around the engine.  You need a cold air intake with a cone. The drop
ins work better because the stock intake has a built in cold air system.
There are some restrictions in the stock intake, but the can be opened up to
help inprove flow.

K&N is not always the best. I personally would not use one. The are filters
out there with similar flow, but which actually filter a lot better. We have
a Holden Commodore in our family with a high performance intake/exhaust. It
uses a filter made by a Japanese company, who's name I can't remember, but
it's costs about 50% more. It uses a felt/velvet surface, with 2 or 3
different densities of foam sandwiched in between. It's very easy to clean,
most of the dust collects on the surface, so you vacuum it and then wash it
The intake on the other side of the filter stays perfectly clean (even after
following the rally of New Zealand on the gravel roads!) - doesn't happen
with a K&N, you find a trail of light dust. If you hold one up to the light,
you can see through it in small spots - how does that filter effectively?

Also the more often you clean your K&N, with the special oil, the less it
filters. They have to bit slightly dirty to be fully effective.


I don't know what's available in the US though. I think K&N's are so popular
because they're easy to find, and marketed well.

Allan Williams
91 325i SE  - Faster than a speeding rice-car!

>
>Date: Tue, 2 Mar 1999 08:05:29 -0700
>From: Frank Cortese <frankc@domain.elided>
>Subject: Air Filters/Cones
>
>I'm was wondering if it is worth changing over to a K&N air filter for my
85
>325e. Does it make that much of a difference over stock air cleaner? And
>what about air cones, they any better (if you can get them for this car,
not
>sure). Any comments regarding this matter would be appreciated. Thanks
>
>Frank
>85 325e

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