Would you all like to see ISO 4548-12 Oil Filter Lab Testing Comparison, Efficiency & Capacity, Pressure vs Flow, Bubble Point, and Burst?

The Subaru filter is part # 152108AA15A. It has I believe a 27 psi bypass valve. Some people believe this is a must and only buy the OE filter or the Wix 57055 that has the same high bypass setting. Others think bypass settings have more to do with what is required based on how well the media flows. All this is tied in with the high flowing Subaru oil pumps and if that requires the higher bypass valve setting.
No doubt the OEM bypass is increased due to the high oil pump flow rates, but some of it could also be due to media flow performance. The flow vs delta-p test would tell if the high bypass setting factor is also due to how the media flows.
 
I think your operating temperature delta p tests are good, but I always wonder about at start up temperatures (0,30,50,70, whatever). On really cold days it takes awhile for oil to get up to operating temperature. The oil is thicker. How does that thicker oil affect delta p. This is the thing I wonder about on Subaru filters. Is the OEM or Wix 27 psi bypass needed to prevent bypass vs a 9-15 psi bypass on most filters at temperatures less than operating temperatures? Everyone says bypass events are limited events. I believe that at operating temperatures, but at cooler temperatures, I have no idea. There doesn't seem to any information on this, that I have seen.

I also think oil makes so many trips through the filter, that if the bypass was open half of all operating time, it would still filter the oil just fine.
 
I think your operating temperature delta p tests are good, but I always wonder about at start up temperatures (0,30,50,70, whatever). On really cold days it takes awhile for oil to get up to operating temperature. The oil is thicker. How does that thicker oil affect delta p.
The delta-p curve will be shifted up more and more as the oil becomes thicker - so at every flow rate the delta-p will be increased. Yes, filters are way more likely to hit bypass with cold thick oil and some engine revs. Key is to keep engine RPM down until the oil warms up, regardless of what engine or filter it is. Yes, I'd say filter bypass events are rare when the oil is at full operating temperature.
 
I think your operating temperature delta p tests are good, but I always wonder about at start up temperatures (0,30,50,70, whatever). On really cold days it takes awhile for oil to get up to operating temperature. The oil is thicker. How does that thicker oil affect delta p. This is the thing I wonder about on Subaru filters. Is the OEM or Wix 27 psi bypass needed to prevent bypass vs a 9-15 psi bypass on most filters at temperatures less than operating temperatures? Everyone says bypass events are limited events. I believe that at operating temperatures, but at cooler temperatures, I have no idea. There doesn't seem to any information on this, that I have seen.

I also think oil makes so many trips through the filter, that if the bypass was open half of all operating time, it would still filter the oil just fine.
We will need to give this some serious thinking and consideration. The bypass at cold temps is a serious concern I am seeing. I have a cold viscosity simulation fluid in the lab we can use for a pressure vs flow. It's a nasty gear oil that smells like garlic. I would have to flush out my system some mineral spirits before and after. I do have data on transmission filter elements using both hot and cold fluid simulations, but the bypass of the housings were always disabled and sealed up, so that wont help us here. My rig gets maxes out at a much lower flow rate using that fluid. Do you happen to have a filter available you can cut open and show me a pic of the bypass valve?
 
70BEF9B0-26C6-4E4B-A4D9-B01C40F4A97A.jpeg
 
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Wix 57055. The bypass spring is very heavy on this filter.
I ordered a 50 lb force gauge and we will see what these springs are set at. We can calculate from there the velocity and flow rates, given our fluid properties, tube diameters, and a few other things that should crack that bypass valve. Then I can stick it on the machine and we can see what happens.
 
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The Subaru filter is part # 152108AA15A. It has I believe a 27 psi bypass valve. Some people believe this is a must and only buy the OE filter or the Wix 57055 that has the same high bypass setting. Others think bypass settings have more to do with what is required based on how well the media flows. All this is tied in with the high flowing Subaru oil pumps and if that requires the higher bypass valve setting.

The Subaru OEM oil filter bypass is set to 1.6 bar aka 23.2psi.

I ordered a 50 PSI force gauge and we will see what these springs are set at. We can calculate from there the velocity and flow rates, given our fluid properties, tube diameters, and a few other things that should crack that bypass valve. Then I can stick it on the machine and we can see what happens.

I for one would love to see a comparison of data you can provide between the Subaru OEM vs. Wix 57055 vs. Fram Ultra XG7317.
 
We will need to give this some serious thinking and consideration. The bypass at cold temps is a serious concern I am seeing. I have a cold viscosity simulation fluid in the lab we can use for a pressure vs flow. It's a nasty gear oil that smells like garlic. I would have to flush out my system some mineral spirits before and after. I do have data on transmission filter elements using both hot and cold fluid simulations, but the bypass of the housings were always disabled and sealed up, so that wont help us here.
I'm just throwing out thoughts and ideas here. If you look at the hot vs cold tests "flow vs delta-p" data on a few filters that you already have data on, is there any repetitive mathematical correlation between the cold vs hot data when comparing different filters? Do they all seem to behave about the same in terms of flow vs delta-p change as a function of oil viscosity? If so, then doing something like described below might be useful, and if not then doing what's described below would probably be a waste of time.

If you had flow vs delta-p data at a few flow rates, and at say at 3 different test oil temperatures of the same test oil (which would be at 3 different viscosities), then I'm wondering if that data could be used to determine/extrapolate the whole flow vs delta-p curve at different oil viscosities. If I recall, you can control the test oil temperature, and if so then you could pick 3 temperatures (and determine the oil viscosity at those temperatures) and find the flow vs delta-p at 3 or 4 flow rates. That might give you enough data to curve fit and find a mathematical relationship for how the flow vs delta-p curve shifts due to different oil viscosity. It would be a (possible time consuming) "science experiment" and unknown how useful it might be or not unless the data was actually measured and analyzed.
 
I'm just throwing out thoughts and ideas here. If you look at the hot vs cold tests "flow vs delta-p" data on a few filters that you already have data on, is there any repetitive mathematical correlation between the cold vs hot data when comparing different filters? Do they all seem to behave about the same in terms of flow vs delta-p change as a function of oil viscosity? If so, then doing something like described below might be useful, and if not then doing what's described below would probably be a waste of time.

If you had flow vs delta-p data at a few flow rates, and at say at 3 different test oil temperatures of the same test oil (which would be at 3 different viscosities), then I'm wondering if that data could be used to determine/extrapolate the whole flow vs delta-p curve at different oil viscosities. If I recall, you can control the test oil temperature, and if so then you could pick 3 temperatures (and determine the oil viscosity at those temperatures) and find the flow vs delta-p at 3 or 4 flow rates. That might give you enough data to curve fit and find a mathematical relationship for how the flow vs delta-p curve shifts due to different oil viscosity. It would be a (possible time consuming) "science experiment" and unknown how useful it might be or not unless the data was actually measured and analyzed.
I will take a look at the data later this week or next week and let you know what I find. I have the capability to run as you describe. Lets think how knowing this potential data could relate to filter design or selection.
 
True indeed ^^^^^^^^^

No wonder how my car has 337,000+ miles on it. Definitely good filters are a big part of that.

Thinking about that.... What filters have I run on my car.

Fram Ultra 7317
Purolator Boss 14610
Purolator One 14610
Purolator Red 14610
Fram EG 7317
Mobil 1 m108+110
Federated Auto XL 14612
Napa Gold 7356
Wix 57356
Wix XP 7356
Hastings LF 240
Fram TG 7317
FRAM Force 7317
Royal Purple 2867
Carquest Red 14610+14612
Carquest Blue 14610
STP XL 6607

Think that's about all of them.
 
I agree with this. I just now caught back up with this thread only because it happened to pop up under "new posts."

I'm anxious to see the results. I just spun a new Fram Ultra on the wife's car yesterday so it better not be the under performer. lol
I have this as a “watched” thread, so if you do happen to start a new one, could you put a note or link in this one to direct followers to the new thread? Thanks!!
 
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