Oil filters for the STi

Spamby

Meat Product Toy
<meat and potatoes from: http://www.igotasti.com/vBforum/showthread.php?5128-OIL-BRANDS-WHATS-BEST-FOR-06-STI/page3&p=75403#post75403 >

This is an excerpt from a previous post (by Spamby), in another thread, that was requested to be stickied. The contents have been left whole.

After doing some more OCD research I have found out the information I believe all of us need. (if you really care and have been paying attention to this thread.)
After reading the attached link to a thread, I wont be cutting any filters open. The gentleman on the Forester forum has already done the work and has very neatly and methodically organized it in a very easy to read post. Leave it up to a fellow Subaru geek :tard: to tweak out on something that may seem very trivial to a lot of others. LOL.

What I have learned is that for filter media size, the Purolator PureOne and Bosch DT are going to be the largest and perhaps the best. As for the bypass pressure rating, WIX/NAPA seems to be the only brand that utilizes the 23 psi rating, besides the Honeywell blue OEM,, as per Subaru, in a direct fitment application. The upfront location of the valve, WIX/NAPA, also prevents the bypassed oil from washing the crud out of the filter media and pushing through the engine.

The reason for the high psi rating for the bypass is for the sake of oiling the engine under certain operating conditions, such as cold start with thick heavy oil or in some instances of high RPM operations or when the media has become dirty. The higher rating keeps the oil flowing through the filter media until the higher psi has been met. The lower ratings on most other filters would mean that some or maybe all of the oil may bypass the filter media at lower operating pressures. This would mean that your oil is bypassing the media more often and thus lubricating your engine with dirty oil more frequently. The sake of having a larger filter media surface would kind of be moot if the oil is being bypassed more frequently.

My thought is that I will change to the WIX/NAPA filter and be done. My OCI (oil change interval) is very low at 2k-3k miles and I don?t need the larger filtering surface as depicted by the BOSCH and Purolator; Which it seems these are really intended for more of an extended OCI.

I have learnt me sunthin today. I hope you have too!

Quick reference for our filters:

NAPA, of course, carries NAPA.
NAPA Gold: P/N: 7712
O?Reilly carries the WIX.
WIX: P/N: 57712

The link to the dissection of the filters plus the specs of each:
http://www.subaruforester.org/vbulle...parison-99130/

The link to what started this all:
http://www.bobistheoilguy.com/forums...Number=2548704

The link, as referenced previously, regarding Subaru bypass specs, etc.:
http://www.bobistheoilguy.com/forums...2056118&page=1
 
The best!!! If you ever wonder why someone tells you to get oil filter X over oil filter Y take a look at this info and you will be eyes wide open. Thanks for putting this up.
 

Grinder34

Track Monkey
I recently came across some info that the OEM Mazda RX-8 (2009+) filter (PN: N3R1-14-302) is a Tokyo Roki filter with the proper bypass pressure. Anyone have any more info on this filter vs, say, the Wix.

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Spamby

Meat Product Toy
Yes. I read about this when I was doing the filter research.
IIRC, them and the subaru filters are made at the same plant, or at least the old subaru filters. (The blues are a Fram product).
As for filtering, I don't believe them to be any better than the wix/napa.
There are lots of filters out there that you can "make" work but in the ease and convenience the napa/wix are easily found and cheap.
 

Grinder34

Track Monkey
Looks like the Tokyo Roki is the new subaru forrester (2012+) OEM filter (PN: 15208AA160)

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Spamby

Meat Product Toy
I believe then that should be the STi filter as well since they use the same filters.
Interesting if this is the case.
 

HolyCrapItsFast

Drinks beer!
Just a clarification about oil filter bypass pressure...

Many people often mis-interpret the bypass pressure rating of an oil filter and associate it with the system pressure. It references only the differential pressure delta between the inlet and the outlet of the oil filter.

As mentioned when the oil is cool and thick, an increased pressure exists at the inlet of the filter because the oil has to squeeze past the filter media. When the difference between the inlet pressure and the outlet pressure exceeds the prescribed amount, the valve is open. So the internal valve doesn't reference system pressure... only it's internal difference.

Beyond that the filter is always doing it's job. Otherwise why have one. My car sees consistent system pressure of 40PSI at an idle. Does that mean that only half the oil is being filtered and the other half is being bypassed by the valve. No :tup:
 
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quality_sound

New member
Ok, really old thread resurrection here.

'14 STi, best filter option? I'll probably go with 5k OCIs (I do a lot of highway driving) and while I plan on tracking, it'll be few and far between unless I get stationed somewhere a lot less in the boonies than I am now.
 

Spamby

Meat Product Toy
Ok, really old thread resurrection here.

'14 STi, best filter option? I'll probably go with 5k OCIs (I do a lot of highway driving) and while I plan on tracking, it'll be few and far between unless I get stationed somewhere a lot less in the boonies than I am now.

I'd still say the Wix or napa. It would be wise to do at least a few oil analysis' in order to get a good idea how your filter and oil are working at that OCI.
 

Spamby

Meat Product Toy
Still using WIX. I had to use a K&N last time cause the store was out of WIX in my part and stopped carrying Bosch. Changed the oil last time and got the WIX.
 

Alin

Diehard Car Enthusiast!
Still using WIX. I had to use a K&N last time cause the store was out of WIX in my part and stopped carrying Bosch. Changed the oil last time and got the WIX.

How much did you pay per filter?
 

IGOTASTi

System Operator
Staff member
I paid about 7 bucks, just shy of. Amazon had a case of 12 for 72 bucks a week or so ago.
Well Platinum members get it at cost. ?
 

Alin

Diehard Car Enthusiast!
I paid about 7 bucks, just shy of. Amazon had a case of 12 for 72 bucks a week or so ago.

$4.70 per filter if you check out that link.
 

Alin

Diehard Car Enthusiast!
That's dealer cost or what that vendor is selling them for ?

Thats not associated to igota or amsoil. Its just a site i found earlier.
 
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