O'Reilley took over Kragan (and Schuck and Checker) auto parts, and I haven't seen a negative yet. Among several
positives is that Wix filters are more accessable. My '01 PF was due for a new air filter, so I decided to try a Wix.
What a difference in construction. Here's a picture of the upstream side, Wix on left, genuine Nissan on the right:



Note the extra pleats (97) on the Wix vs. less (53) on the Nissan. The size of the Wix pleats is either the samas
or a touch more than the Nissan. Surface area is what counts in filters. Doubling the
surface area will more than double the useful life.

Here's the down stream side:



Note that the paper filter is backed up with expanded metal in the Wix.

FTR, the Wix was $13.49+tax. I don't remember what the Nissan but I recall about $20.
Courtesy wants $16.46 for a slightly different part number (16546-R50001 vs my 16546-02000).

O'Reiley had two other brands: Fram, and another I hadn't heard of that made some big
claims on their boxes. I may go in and ask to take pictures.

Chuck

I use Spectre oiled cotton gauze performance filter and it's been good so far, only $20 at AutoZone and it's washable.

A key question is: What gets through? That's what concerns me about the "oiled" filters. They have big gaps and depend
on particles running into the oiled fibers to keep them out. Random chance says SOME of the big nasty particles will
get through and tear things up. Filters with small openings get everything bigger than the opening, and some of the smaller
particles.

IMHO, the ideal filter for NASTY conditions (off-road, dust and sandstorms, etc.) is an oiled filter backed up with a paper
filter. But for general down the road use, paper filter should be fine.

IIRC, post-Mt.St.Helens, there was an air filter analysis. If somebody has a URL, please post.

BTW: My PF turned over 190,000 miles this weekend. For general down the road use, I must be doing something right.

BTW2: Christmas 2009, Adm. Linda and I drove my 1987 Corvette to from Morgan Hill (south end of Silicon Valley) to
Tucson, AZ (about 840 miles) and ran into a dust storm. I replaced the air filter (with a Wix) in Tucson, and changed the oil
and filter (with a Wix) when we got home. I'm most grateful it wasn't quite a sandstorm (which sand blasted the windshield
on my 240Z ca 1985) but for filters, when in doubt, replace.

BTW3: If you come up on a localized duststorm (usually a farmer on his tractor), put the clutch in and coast through.
That will minimize the amount of dust sucked into the filter).


Chuck

Chuck check out the Amsoil filters. They are around $40 but you use them for 4 years. They use a nano fiber technology to keep the particles on the surface of the filter so you can clean them once a year. As well that nano fiber catches very small particles. I have one in my Q and its great.

amsoil makes air filters for our cars? ive searched alot and couldnt find one. Link please!!!

Here is the link for the filter that fits your Q.
http://www.amsoil.com/catalog.aspx?code=EAA74-EA

Here is a link on how it works.
http://www.amsoil.com/storefront/eaa.aspx

I've had mine in for 6 months now. You clean them once a year with an air chuck or vacume off the dust.