Air filtration does severely impact wear indicators in UOA.
It's sensible to conclude the air filtration is about the most important
thing to take care of in terms of "extra lubricant" aggravating conditions.
Coolant would be another one, but not much to be done there inapreemptive
manner other than tending properly to your cooling system to prevent
corrosion eventually allowing coolant to migrate into the oil / combustion
chamber.

 

Thanks for the welcome I will check that part of the forum out.

 

I missed the white OEM filters when the black ones came out because the black ones were smaller, purely to keep heat from radiating from the headers, into the oil via the filter. My headers are heat wrapped so I felt like the smaller filter was a compromise I didn't need to make. Also the undertray on the bugey is shorter and probably allows more cool air to curl up and hit the filter, keeping it cool.

This is just a stab in the dark, but perhaps the reason SOA came out retroactively stating that all turbo Subarus should change their oil at 3-4K miles instead of the 7.5K the owner's manual lists, was because these new filters (being smaller) needed to be changed more often.

Anyway, for my last oil change, I was all out of OEM filters so I did some research on bobistheoilguy and went with the Purolator Pure One. It was really cheap, like $5 IIRC and textured for easy removal by hand. If you tell them you have a MY03, they'll give you the larger ones that are like the OEM white filters that were available when my '03 was new.

 

If you're willing to travel to palo alto this is the best place to get your oil changed

http://www.yelp.com/biz/nine-minute-...lube-palo-alto

 

Word. I replaced the K&N drop-in with OEM before my last tune. I'm sure it's not worth any power on a stage 2 2.0L anyway. But after seeing an independent test that showed that K&N and, for the most part, all non-paper media air filters suck at filtering out particulate, I couldn't keep it.

 

The factory Subaru air filter flows better than the K&N air filter because it has
more surface area (easily calculated by the number of pleats).The K&N filter
cannot match this because the gauze and mesh construction is too thick to
construct a filter with the same number of pleats that fits within the confines of the stock factory air box.I would stick with a non-oiled filter element for a Subaru. Overtime,the K&N will tend to leave a fine oily film on the MAF sensor,
leading to sensor errors and subsequent ECU adjustment of the air/fuel ratio.MAF sensor can be carefully cleaned by hand but why go through the trouble for no power gain?

Concerning the K&N drop-in panel air filter vs. the factory Subaru OEM
paper pleated filter element,Paul@DB Tuned verified a slight loss on his AWD dyno.Shiv at Vishnu Performance found the same results in testing on his dyno.

 

The 3rd party test (which I found years ago on here, but the link became dead a couple years ago) indicated that the K&N did indeed flow better (it's practically a screen door with a thin layer of gauze over it) but it let tons of particulate into your motor.

Ed of EQ Tuning has told me that you shouldn't change your type of drop-in after being tuned since it will effect your AFR's. This is counterintuitive because you'd think the MAF would easily compensate for a difference in flow, but apparently the turbulence profile or something changes things.

I was always careful to not over-oil the K&N and to clean/check the MAF for oil regularly and it always appeared clean.

 

Heh, you actually posted in that thread, WRX409.

https://www.i-club.com/forums/showpo...8&postcount=34

 

shell rotella 5w40
oem filter
crush washer
your car will thanks you.
RP/M1/amsoil are all over priced and dont do much.RP is responsible for my engine issues.and i have a oil analysis tp prove it.

 

How did RP cause engine issues? If there's a thread on this, please link me.