Reason I Use Subaru OEM Oil Filters

[Nick1994]

Quote:
Variable density paper is more expensive than common aftermarket paper filter


The poor grammar used just screams phony.

 

[ARCOgraphite]

Originally Posted By: GravelRoad
Originally Posted By: ARCOgraphite
Probably better off running HONDA/NISSAN style filter on the NA engines to get the bypass in a "NORMAL" range. I did try a big wix once and the engine poo poo'd it.

21-23PSIG sounds too racy to me. Any logic to the high baypass other than keeping crunchy bits out of the turbo oiler banjo fitting screen on the killer turbos?


This is a 2.5 non turbo. My understanding for the oil filter 23.2 psi bypass setting is the high discharge rate of the oil pump. keeping it out of bypass as much as possible.
From my 2016 Shop manual:

Oil temperature at 248°F

600rpm discharge rate one minute 6.1 quarts. (1.525 gallons per minute)

6000rpm discharge rate one minute 58.1 quarts. (14.525 gallons per minute)




Imagine your garden hose set to stream vs full. The well pump can give you 15gpm but you are RESTRICTED to say 5 GPM. The engine block oil drills and bearing clearances dictate oil flow.
The pressure delta around the filter is MINIMAL (typ less than 1-2psi).

I can explain the turbo oiling and race performance - but I d rather have blue subie do it

Simply though blipping the throttle ( rev matching) whilst shifting at high rpm with HOT, THIN oil will exhibit spike and momentary bypass.
And there goes the semi captured particulate in the filter dome - RIGHT TO THE BEARINGS. Or as they did in the EJ turbos clogging up the turbo banjo oiling fittings and screens.

 

[ZeeOSix]

Originally Posted By: ARCOgraphite
Imagine your garden hose set to stream vs full. The well pump can give you 15gpm but you are RESTRICTED to say 5 GPM. The engine block oil drills and bearing clearances dictate oil flow. The pressure delta around the filter is MINIMAL (typ less than 1-2psi).

With a positive displacement oil pump, it's the pump's pressure relief valve that controls the maximum oil pressure, which in turn restricts the maximum oil flow through the resistance of the oiling system.

As the oil heats up and thins down, there will be higher flow volume rate through the same oiling system at the same pump pressure relief setting. When the oil is cold and thick, the pump's pressure relief kicks in much earlier with less flow volume because it takes much more pump pressure to force the oil through the oiling system.

 

[ZeeOSix]

Originally Posted By: GravelRoad
This is a 2.5 non turbo. My understanding for the oil filter 23.2 psi bypass setting is the high discharge rate of the oil pump. keeping it out of bypass as much as possible.
From my 2016 Shop manual:

Oil temperature at 248°F

600rpm discharge rate one minute 6.1 quarts. (1.525 gallons per minute)

6000rpm discharge rate one minute 58.1 quarts. (14.525 gallons per minute)


Part of the reason the filter's bypass valve could be set so high is because of the restrictiveness of the filter itself. You probably won't find any technical info on the Subaru OEM filter's delta-p vs flow characteristics anywhere. But I do think most of the reason it's set high is because Subaru doesn't want the filter to bypass unless it's really clogged up, regardless if the filter is really restrictive when new and/or from the high pump flow rate.

The 14.5 GPM at 6000 RPM spec might be the pump's raw output without pressure regulation ... hard to say unless the Subaru manual says something specific to determine that, or does it somewhere indicate that 14.5 GPM is at pump relief with 248 deg oil. If that's really the case, then that's a lot of oil flow.

 

[GravelRoad]

Originally Posted By: ARCOgraphite
Originally Posted By: GravelRoad
Originally Posted By: ARCOgraphite
Probably better off running HONDA/NISSAN style filter on the NA engines to get the bypass in a "NORMAL" range. I did try a big wix once and the engine poo poo'd it.

21-23PSIG sounds too racy to me. Any logic to the high baypass other than keeping crunchy bits out of the turbo oiler banjo fitting screen on the killer turbos?


This is a 2.5 non turbo. My understanding for the oil filter 23.2 psi bypass setting is the high discharge rate of the oil pump. keeping it out of bypass as much as possible.
From my 2016 Shop manual:

Oil temperature at 248°F

600rpm discharge rate one minute 6.1 quarts. (1.525 gallons per minute)

6000rpm discharge rate one minute 58.1 quarts. (14.525 gallons per minute)




Imagine your garden hose set to stream vs full. The well pump can give you 15gpm but you are RESTRICTED to say 5 GPM. The engine block oil drills and bearing clearances dictate oil flow.
The pressure delta around the filter is MINIMAL (typ less than 1-2psi).

I can explain the turbo oiling and race performance - but I d rather have blue subie do it

Simply though blipping the throttle ( rev matching) whilst shifting at high rpm with HOT, THIN oil will exhibit spike and momentary bypass.
And there goes the semi captured particulate in the filter dome - RIGHT TO THE BEARINGS. Or as they did in the EJ turbos clogging up the turbo banjo oiling fittings and screens.


ARCOgraphite, I agree with your explanation. Don't know how my thread moved to turbos, banjo screens, etc.

Should of added this to may last post on oil pump discharge rate:

(2016 Subaru Outback w/FB25)

Oil Pump:
Relief valve working pressure
(2-step relief)

1st opening pressure 21.7 psi
Main opening pressure 82.6 psi

If I remember correctly, the FB20 turbo a single pressure relief around 100 psi.
I do not know what the EJ25 turbos had.

Does this mean my oil pump is in relief mode (1st opening pressure) when cruising, say at 2,000 rpm?
(Don't know the oil pressure or flow at that rpm)

 

[ZeeOSix]

Originally Posted By: GravelRoad

(2016 Subaru Outback w/FB25)

Oil Pump:
Relief valve working pressure
(2-step relief)

1st opening pressure 21.7 psi
Main opening pressure 82.6 psi

If I remember correctly, the FB20 turbo a single pressure relief around 100 psi.
I do not know what the EJ25 turbos had.

Does this mean my oil pump is in relief mode (1st opening pressure) when cruising, say at 2,000 rpm?
(Don't know the oil pressure or flow at that rpm)


Not sure about the 2-step oil pressure relief. Could be the 1st pressure relief opening is oil temperature controlled during warm-up. These newer cars are starting to use computer controlled oil pumps for volume and pressure control. If you have the full blown factory service manual it may explain the operation of the oil pump in better detail.

 

[GravelRoad]

Originally Posted By: ZeeOSix
Originally Posted By: GravelRoad

(2016 Subaru Outback w/FB25)

Oil Pump:
Relief valve working pressure
(2-step relief)

1st opening pressure 21.7 psi
Main opening pressure 82.6 psi

If I remember correctly, the FB20 turbo a single pressure relief around 100 psi.
I do not know what the EJ25 turbos had.

Does this mean my oil pump is in relief mode (1st opening pressure) when cruising, say at 2,000 rpm?
(Don't know the oil pressure or flow at that rpm)


Not sure about the 2-step oil pressure relief. Could be the 1st pressure relief opening is oil temperature controlled during warm-up. These newer cars are starting to use computer controlled oil pumps for volume and pressure control. If you have the full blown factory service manual it may explain the operation of the oil pump in better detail.


Thank you ZeeOSix. I have a pdf of the factory service manual. (309mb)
Could not find any details other than the specs for the oil pump. It does say it is non repairable only replacement.

Think I'll start a new thread for the 2-step oil pump pressure relief. First I heard of one.

 

[ZeeOSix]

Originally Posted By: GravelRoad
Originally Posted By: ZeeOSix
Originally Posted By: GravelRoad

(2016 Subaru Outback w/FB25)

Oil Pump:
Relief valve working pressure
(2-step relief)

1st opening pressure 21.7 psi
Main opening pressure 82.6 psi

If I remember correctly, the FB20 turbo a single pressure relief around 100 psi.
I do not know what the EJ25 turbos had.

Does this mean my oil pump is in relief mode (1st opening pressure) when cruising, say at 2,000 rpm?
(Don't know the oil pressure or flow at that rpm)


Not sure about the 2-step oil pressure relief. Could be the 1st pressure relief opening is oil temperature controlled during warm-up. These newer cars are starting to use computer controlled oil pumps for volume and pressure control. If you have the full blown factory service manual it may explain the operation of the oil pump in better detail.


Thank you ZeeOSix. I have a pdf of the factory service manual. (309mb)
Could not find any details other than the specs for the oil pump. It does say it is non repairable only replacement.

Think I'll start a new thread for the 2-step oil pump pressure relief. First I heard of one.


You hang out on a Subaru chat board? They might know what that 2-step oil pump is all about.

 

[alarmguy]

It looks like a cheap Fram with cardboard end caps. I am a little surprised. Not that it matters, it will do its job.

 

[ARCOgraphite]

It is a "fram". What s wrong with cardboard endcaps? The filter is paper and polyester and glass and rag?