23psi bpv oil filter for WRX?

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Hey guys, I have done some reading, and it seems that my car (05Wrx) or most Subaru's in general "need" an oil filter with a 23psi bypass valve in it, due to the relatively high volume and pressure of the oem Subaru oil system.

From the research I have done, it seems almost all major oil filter manufacturers (Wix, Bosch, Mobil1, K&N, Fram etc) offer us filters with 8-12 psi bypass valves, meaning oil would bypass the filter most of the time.

Supposedly Purolator makes a filter for us with 16 or 18 psi bypass valve, I believe.

It seems like the "older" "black" oem Subaru filters were of better quality than the newer "blue" oem filters (made by Honeywell...Fram?) But seems impossible to find.

Are there any good non-oem oil filters that offer 20-23 psi bypass valves in them?
Anyone know where to find the black Subaru filters?

I have read that 09? and newer Mazda Rx8's used the same filter as the earlier black Subaru filters, just with Mazda on it. I also read '12? and new H6 Subarus do as well. But I have no Idea.
 
Purolator says its 14-18 Psi with anti drain back valve.

I want one with 23 psi and Im pretty sure the adb valve is pointless the way the filter is mounted.
 
K&N says 11-17 for their hp1008.
Seems to be same for M1108 and others.


I have read a bunch of people saying the blue Fram Subaru filters seem to leak at the gasket, and have very thin, weak canisters with [censored] filter material. But, has correct 23psi bpv.
I have read a bunch that the earlier black Tokyo Roki? filters are stronger, have better filter media and higher quality overall but were replaced with the blue Fram.

But, I have read that new Subaru's are using Tokyo Roki? filters, but, I have no confirmation if they do, or if the are right for my engine. Which I would love to know. I would also love to know if any retailer has 6 or 12 TR black Subaru filters.
 
Yeah I did read about the recall on the blue filter. As well as quite a few reviews about them leaking, and having poor filter element and weak/cheap construction.

I really REALLY wish I could find 12 oem Subaru Tokyo Roki oil filters.

Or knew much more about the Rx8 TR and newer Subaru H6 TR filters. I have read that they thread on just fine and have the 23 psi bpv, but don't know if "bigger" means longer, or larger diameter making it really close to the exhaust manifold.

Also read Subaru BRZ has Tokyo Roki filters that should fit.
 
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The pressure that the oil pump puts out has nothing to do with PSID(bypass). My S2000 runs 85+ oil pressure going down the freeway and I run a 14 lbs bypass filter. My motorcycle runs over 100 lbs of oil pressure and its filter has 10 or 12 lbs bypass filter.

ROD
 
Why not the Wix 57712? You can buy a dozen for about $5+ a piece delivered Meets the specs you are looking for and are top filters

By-Pass Valve Setting-PSI: 23
Anti-Drain Back Valve: Yes
Beta Ratio: 2/20=2/20
Burst Pressure-PSI: 300
Max Flow Rate: 9-11 GPM
Nominal Micron Rating: 21
 
There is a reason Subaru specifically spec'd their filters to 23psi instead of 8-14 like most oil filters. I do not want to be driving around with my oil bypassing the filter because I bought the wrong filter. I am looking for a good (better than oem Fram) oil filter with 23 psi bypass valve.

My first choice is the old 15208aa100 Subaru Tokyo Roki, but I cant find those anymore.

I would like information on the oem Rx8 To Ro filter, Subaru H6 To Ro filter, and Subaru Brz To Ro filter, pertaining to my 05 Wrx.
 
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Originally Posted By: 94exa2
Purolator says its 14-18 Psi with anti drain back valve.

I want one with 23 psi and Im pretty sure the adb valve is pointless the way the filter is mounted.


If Purolator specs that oil filter for that engine, then they have taken into consideration the performance characteristics of the oiling system ... ie, the oil viscosity used and the max flow volume of that engine to determine what the expected max delta-P is across their filter with loading factors included. All of that is used to determine what the by-pass valve should be set at.

If you compare every oil filter that is specified for that engine, they will not all have a 23 PSI by-pass valve like the Subaru OEM. That's because the design of the filter itself is also a factor on where the by-pass valve is set - ie, how the filter flows, how much media and what type of media is has.

If you are paranoid that an aftermarket filter maker didn't design their oil filter correctly that is specified for that engine, then stay with the OEM filter.
 
The little Wix? I guess I could get them a try if all else fails.

If I can find a case of the older oem Subaru Tokyo Roki oil filter I would buy those. If the Rx8 Tokyo Roki filter is the same as the one that used to be for the Wrx with 23psi I might go that route. If there are any other Subaru's that use oem Tokyo Roki filters that are suitable for my Wrx, I might got that route.

I just really want to stay with 23 psi as per Subaru.
And always hear/read oem To Ro is much better than oem Fram.
And heard/read those are the only two options with 23psi.
Until now, I guess Wix finally wised up and made one as well.
Honestly don't know why it's hard to find the correct one, other than the $5 cardboard Fram. (Mobil, Purolator, K&N, etc should, since there does seem to be a demand for them)
 
Originally Posted By: 94exa2
The little Wix? I guess I could get them a try if all else fails

)


Not sure why the "little" Wix comment? If you are describing the diameter, I was told the filter was spec 'd smaller because where it sits. On our 07, it is completely surrounded by exhaust pipe. You literally fit your hand/wrench in between almost a circle of pipe. The larger diameter filters were too close to the exhaust, heating up the filter/oil so Subaru went to a smaller diameter filter rather than the trouble of moving where the filter is located.
 
Post #57 in the Nasioc forum linked above:

"Well, 25-27 psi is really close to 23, so that's a pretty small difference. Since pressure drop is a serial phenomenon, there would potentially be less pressure at the bearings and less pressure available to operate the AVCS. I stress potentially though, that would only be true when the filter was close to bypassing."

He doesn't realize that with a positive displacement oil pump (key to the discussion), the flow and pressure throughout the system is still the same, even if there is a larger pressure drop across the filter. What a more restrictive filter does do however, is make the pump output pressure increase accordingly to maintain the same flow and pressure in the engine, and this puts the pump closer to its pressure relief setting. But a more restrictive filter doesn't reduce the flow or pressure to the bearings up to that point.

The only time there would be a reduction of flow and pressure to the bearings is when the oil pump has hit pressure relief and the filter's restrictiveness has caused reduced flow due to increased resistance - as compared to a less restrictive oil filter.

The only reason I can see why Subaru uses such a high bypass valve setting is because their filter must be somewhat flow restrictive, and that combined with a high volume oiling system, and what ever factor they have thrown in for debris loading, causes the bypass setting to 23 PSI.

As I said earlier, if a filter manufacturer has specified a filter for a Subaru application that normally uses an OEM filter with a 23 PSI bypass setting, then the reason the aftermarket filter has a lower setting is probably because it flows better, and maybe they didn't put such a large safety margin on the bypass setting for debris loading, etc.
 
Originally Posted By: ZeeOSix


As I said earlier, if a filter manufacturer has specified a filter for a Subaru application that normally uses an OEM filter with a 23 PSI bypass setting, then the reason the aftermarket filter has a lower setting is probably because it flows better, and maybe they didn't put such a large safety margin on the bypass setting for debris loading, etc.





"Higher flowing", as in, in bypass mode constantly? I could see that flowing alot more than actually going through the filter media...
 
Originally Posted By: 94exa2
Originally Posted By: ZeeOSix

As I said earlier, if a filter manufacturer has specified a filter for a Subaru application that normally uses an OEM filter with a 23 PSI bypass setting, then the reason the aftermarket filter has a lower setting is probably because it flows better, and maybe they didn't put such a large safety margin on the bypass setting for debris loading, etc.


"Higher flowing", as in, in bypass mode constantly? I could see that flowing alot more than actually going through the filter media...


I'm talking about a "higher flowing" filter with the bypass valve always being closed. When oil flows through the media, it causes a pressure difference ("PSID" or "delat-P") across the filter. Here's an example of how the delta-P increases with increased oil flow while keeping the viscosity constant.

http://www.bobistheoilguy.com/forums/ubb...451#Post1619451

Variables that effect how much delta-P is produced across an oil filter are:
1) Flow performance per square inch of the media.
2) Total square inch area of the media (as area goes up, delta-P goes down if everything else is constant).
3) Oil flow volume.
4) Oil viscosity.
5) Debris loading rate vs. filter change interval.

All of these factors are considered when the filter designer comes up with a filter's bypass valve setting.
 
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