Highest flow filter?

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Flow is gals/min or other units. Restriction is psid or lbs/sq in. in this situation. Why does an 0w get to the heads faster than 40 on a cold day? I think it must be the oil pump has losses or the oil pump relief opens. So use a new filter every change and lightest oil cold rating possible for fastest, filtered, oil to heads. Look at the cold viscosity numbers. it shouldn't matter which filter, like the lady said.
 
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….Keep in mind that most oil filters are only about 1/15th the flow restriction than the engine's oiling system is.....
I do and thus I don't concern myself with filter flow in PC use. So, I'd say all of the filters mentioned will "flow" just fine. More/most important is matching the filter to it's intended service interval, OCI/FCI. That and 'if' efficiency important, taking that into consideration.
 

dnewton3

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The positive displacement pump will put out "X" gpm and develop "A" psid. Immediately after the pump will be a relief valve; it will reduce "X" to a lower value of "Y", because some flow is bled off. Same goes for pressure; "A" will drop to "B" in value, based on the relief setting. After the relief the oil will get to the FF filter, where there is essentially no flow loss, but perhaps a minuscule amount based on dP; "Y" now becomes "Z" in value. PSI also drops from "B" to "C" in value. The filtered oil will then go to the engine, where it goes on various routes and sees the flow will drop to a low value once it's in a "free fall" state in the sump. And the dP drops from "C" back to atmospheric And ... pretty much none of this matters. The pump will provide WAY more oil than the engine needs for it's given rpm. The relief will retain more than enough pressure to sustain the film boundary. The filter will reduce particulate and yet is capable of passing well more oil than the engine can consume. I will jump into an analogy that I just recently enjoyed reading elsewhere here on BITOG ... Q: Is a 15 foot ladder "better" than a 12 foot ladder, if the hole you have to climb out of is only 10 feet deep? A: No; there is no tangible benefit from the added capacity - it goes unused (wasted). Once something is good enough for the job, having more capacity does not factor into the equation unless the conditions of application dictate a change is needed. Pretty much ANY oil filter offered for public sale on the shelf anywhere has WELL MORE than enough flow capacity for the applications they are marketed for. How many times do we have to discuss this?
 
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4WD

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X and A are not fixed … gear pump and rotor pump output is an RPM derivative (small variation from viscosity as well) which is always changing hence the PRV attempts to keep that somewhat in balance. Then variable displacement pumps came along where the OEM became concerned with bypass setting within the filter … many are not correct. (some have said they put out less … actually higher or lower and become less parasitic when demand is low) I don't like the ladder length analogy … the load rating of the ladder, like other things is where safety factors come from. This graph shows variables in distribution of engine oil flow:

B357827D-5931-4251-AA1E-A77AC3B40F6C.jpeg
 

dnewton3

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Originally Posted by 4WD
X and A are not fixed … gear pump and rotor pump output is an RPM derivative (small variation from viscosity as well) which is always changing hence the PRV attempts to keep that somewhat in balance. Then variable displacement pumps came along where the OEM became concerned with bypass setting within the filter … many are not correct. (some have said they put out less … actually higher or lower and become less parasitic when demand is low) I don't like the ladder length analogy … the load rating of the ladder, like other things is where safety factors come from.
I never said X and A are fixed; I agree they are rpm dependent in most applications. As for the ladder, I apologize; I'm sorry you didn't understand the inference that all other conditions are being kept equal. Really? The analogy escaped you that easily? Don't nit-pick where needlessly unwarranted. The point is that the length of the ladder is what achieves the goal; the load rating, rung width, etc are not in play here because they are presumed equal between choices. That you call this out means you don't understand simple analogies. Further, I don't believe I've seen any statement or data that would lead me to conclude that OEM are changing to variable displacement pumps because of oil filter bypass setting variation. What I've read is that VD pumps are able to let them tailor the pump output (which directly affects pump energy consumption) to the load conditions and providing a satisfactory film barrier. When light loads are experienced, they can run a lower dP and flow, which consumes less energy, which consumes less fuel. It ain't about what Fram or Wix is doing with the bypass setting. That being your assertion, I'll ask you to provide a link of proof please.
 
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Just the facts. The logic tree you constructed is simple and descriptive of the important data. There is a lot of noise in data that some individuals focus in on, that in application has little to no relevance on outcomes.
Originally Posted by dnewton3
The positive displacement pump will put out "X" gpm and develop "A" psid. Immediately after the pump will be a relief valve; it will reduce "X" to a lower value of "Y", because some flow is bled off. Same goes for pressure; "A" will drop to "B" in value, based on the relief setting. After the relief the oil will get to the FF filter, where there is essentially no flow loss, but perhaps a minuscule amount based on dP; "Y" now becomes "Z" in value. PSI also drops from "B" to "C" in value. The filtered oil will then go to the engine, where it goes on various routes and sees the flow will drop to a low value once it's in a "free fall" state in the sump. And the dP drops from "C" back to atmospheric And ... pretty much none of this matters. The pump will provide WAY more oil than the engine needs for it's given rpm. The relief will retain more than enough pressure to sustain the film boundary. The filter will reduce particulate and yet is capable of passing well more oil than the engine can consume. I will jump into an analogy that I just recently enjoyed reading elsewhere here on BITOG ... Q: Is a 15 foot ladder "better" than a 12 foot ladder, if the hole you have to climb out of is only 10 feet deep? A: No; there is no tangible benefit from the added capacity - it goes unused (wasted). Once something is good enough for the job, having more capacity does not factor into the equation unless the conditions of application dictate a change is needed. Pretty much ANY oil filter offered for public sale on the shelf anywhere has WELL MORE than enough flow capacity for the applications they are marketed for. How many times do we have to discuss this?
 
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I must admit in younger days I would let the clutch out at a stop light and pull the rpm down on the Ford F 150 with 300 straight six, and could hear the bearings knock and the oil pressure go to almost zero on the gauge. At idle the oil pump is not always pumping too much oil, probably just enough to prevent damage depending on main bearing condition and make.
 
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Originally Posted by dnewton3
After the relief the oil will get to the FF filter, where there is essentially no flow loss, but perhaps a minuscule amount based on dP; "Y" now becomes "Z" in value. PSI also drops from "B" to "C" in value.
All oil volume leaving the pump heading to the filter will go through the filter. The delta-p across the filter does not change the flow through the filter.
 
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Originally Posted by dnewton3
...Pretty much ANY oil filter offered for public sale on the shelf anywhere has WELL MORE than enough flow capacity for the applications they are marketed for. How many times do we have to discuss this?
Probably at least once every week until the supply of slow learners runs low.
 
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Originally Posted by dnewton3
The positive displacement pump will put out "X" gpm and develop "A" psid. Immediately after the pump will be a relief valve; it will reduce "X" to a lower value of "Y", because some flow is bled off. Same goes for pressure; "A" will drop to "B" in value, based on the relief setting. After the relief the oil will get to the FF filter, where there is essentially no flow loss, but perhaps a minuscule amount based on dP; "Y" now becomes "Z" in value. PSI also drops from "B" to "C" in value. The filtered oil will then go to the engine, where it goes on various routes and sees the flow will drop to a low value once it's in a "free fall" state in the sump. And the dP drops from "C" back to atmospheric And ... pretty much none of this matters. The pump will provide WAY more oil than the engine needs for it's given rpm. The relief will retain more than enough pressure to sustain the film boundary. The filter will reduce particulate and yet is capable of passing well more oil than the engine can consume. I will jump into an analogy that I just recently enjoyed reading elsewhere here on BITOG ... Q: Is a 15 foot ladder "better" than a 12 foot ladder, if the hole you have to climb out of is only 10 feet deep? A: No; there is no tangible benefit from the added capacity - it goes unused (wasted). Once something is good enough for the job, having more capacity does not factor into the equation unless the conditions of application dictate a change is needed. Pretty much ANY oil filter offered for public sale on the shelf anywhere has WELL MORE than enough flow capacity for the applications they are marketed for. How many times do we have to discuss this?
Until the thread goes to "page 2". Yes that is the usual life of threads on the internet, page 1. Like clouds in the sky passing through. We put so so much importance on something that either won't be remembered or ever read again. Who goes to page 2? I never do. So people ask over and over the same things and it never ends. This is page 2. I am talking about the main page after the first main page whatever it is called in forumese.
 

4WD

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What a snarky reply from a moderator … you know good and well I meant safety factors …
 

4WD

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Well … my variable output oil pumps are ECM controlled and based on logic. When the PLC says everything gets oil at startup … then everything including oil to the piston jets gets plenty cold oil … hence the higher PRV in the filter. Later … it moves the axis of symmetry between rotor and stator (vanes have a wider gap) and at that point it will minimize how much torque gets wasted by lowering output and less to relief. This can also help control heat in concert with a more advanced oil cooling and engine cooling system when compared to my 2010. Trying to connect dots on a ground up redesigned lubrication system is not always straightforward
 
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Kah-nah-dah
The XP is a rock catcher and will flow the most. Fram Ultra will flow as well and actually filter... LoL I am a hater of Wix XP aka Napa Platinum
 
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Originally Posted by gamefoo21
The XP is a rock catcher and will flow the most.
It can't flow any more than any other filter that doesn't put the pump in pressure relief.
 
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Originally Posted by ZeeOSix
Originally Posted by gamefoo21
The XP is a rock catcher and will flow the most.
It can't flow any more than any other filter that doesn't put the pump in pressure relief.
Or the filter enters bypass because the media becomes the restriction. If your pump is moving 10GPM and the filter can only filter 8GPM before crossing the pressure differential to open the bypass. Guess which opens first... It's not the oil pumps bypass, it's the filter's. If the filter media sees 50 psi, behind the media is at 44 psi and the filter bypass is set for 6 psi. The filter is still filtering what it can, but the bypass opens and stabilizes the difference by flowing unfiltered oil. It of course only flows enough to keep the valve open a certain amount. The bypass in the filter can also be a restriction point if the flow is high enough, and that can definitely cause the oil pump force open it's bypass.
 
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Originally Posted by gamefoo21
Originally Posted by ZeeOSix
It can't flow any more than any other filter that doesn't put the pump in pressure relief.
Or the filter enters bypass because the media becomes the restriction. ...
That's theoretically true, but realistically irrelevant for most people, because it ain't gonna happen unless your engine is full of junk, or the oil is way too thick for conditions.
 
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Originally Posted by gamefoo21
Originally Posted by ZeeOSix
Originally Posted by gamefoo21
The XP is a rock catcher and will flow the most.
It can't flow any more than any other filter that doesn't put the pump in pressure relief.
Or the filter enters bypass because the media becomes the restriction. If your pump is moving 10GPM and the filter can only filter 8GPM before crossing the pressure differential to open the bypass. Guess which opens first... It's not the oil pumps bypass, it's the filter's.
It all depends on the filter and the oil pump valve settings, the restriction of the filter and engine oiling circuit, and the oil viscosity and temperature. Typical engine oiling systems are around 15 times more restrictive than typical oil filters. So if the oil is very cold and thick, the engine restriction will drive the pressure output up at the pump outlet much more than the filter will. The filter may or may not bypass before the pump hits relief pressure - it all depends on the factors described in the 1st paragraph. When the oil is hot, typically the pump will never put out enough flow to open the pump relief or the filter bypass valve, unless the filter is clogged up pretty bad. There would have to be a huge difference in the filter's "flow vs psid" curve to make any real difference with hot oil. You might see 3~4 PSI difference max between filters with hot oil. I think more and more manufscturers are increasing filter bypass valve setting to help reduce cold start filter bypassing with increased RPM conditions with cold oil. In cases like that, it's more likely for the pump to hit pressure relief before the filter goes into bypass Bottom line is keep the RPM low until the oil warms up pretty good.
 

dnewton3

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Originally Posted by ZeeOSix
Originally Posted by dnewton3
After the relief the oil will get to the FF filter, where there is essentially no flow loss, but perhaps a minuscule amount based on dP; "Y" now becomes "Z" in value. PSI also drops from "B" to "C" in value.
All oil volume leaving the pump heading to the filter will go through the filter. The delta-p across the filter does not change the flow through the filter.
You are correct, but I was allowing for tiny fractional losses like leaks after the pump but before the filter (think of a seal leak prior to the filter; volume loss there). As I said, it's minuscule and not really worth noting, but in BITOG land, we always risk either over-stating or under-stating something. I probably shouldn't have mentioned it, but as soon as I did, there'd be a yabut tossed my way ... (the following isn't directed at Zee, but just the general reading public) BOTTOM LINE: I don't want a filter with the "best" of anything. I want a filter that provides a minimum of adequate flow and efficiency for the intended duration I will put it into, for the least cost. "Adequate" does not mean inferior; it only means "meets the desired performance criteria". If I want a filter that's 90+%, and rated to 10k miles, then there are a fairly decent roost of choices on the shelf. There's no data I've ever found that would indicate flow is even a risk at that 10k mile limit. Most of us don't have any idea what the true flow needs actually are for any given rpm. Even Jim Allen, when he did his dP experiments, didn't bother tracking flow; he knew that the flows were what they were, and no amount of bickering was going to change them. I am supremely confident that any decent brand filter I choose will have the efficiency and flow needed at the OCI duration I'll induce, and yet STILL have some excess capacity when I toss it in the garbage ... I don't need to spend more money to waste more capacity on a "better" filter. I've driven a few vehicles to their death. Sometimes timely, and sometimes untimely. I've retired vehicles due to salt-induced corrosion, or being totaled in a wreck. At times, I've just got bored and wanted something different; traded it out before any natural cause took it out of service. And not once have I had to retire a vehicle because it quit running due to my filter selections (of which there have a scads of choices used over these past decades). I do not fault anyone whom spends their hard earned money the way they see fit; more power to them! But I do take issue when folks imply that using anything less than top-tier products is somehow an inference that I'm not caring for my vehicles well enough. As if "best" is only satisfied by, and defined as, the most money spent. Pretty much any filter I can think of on the market today will flow WELL more than the engine needs it to. So why do we continuously debate the merits of excessive capacity when it's never been proven to be of any consequence?
 
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Originally Posted by dnewton3
Even Jim Allen, when he did his dP experiments, didn't bother tracking flow; he knew that the flows were what they were, and no amount of bickering was going to change them.
Like I mentioned earlier two posts above, when the oil is hot there's probably not any brand name filter that will go into bypass or any stock engine that will hit oil pump pressure relief. I could never get my Z06 to hit pump relief even at redline when the oil was fully hot - same results of oil pressure vs engine PRM with 4 different brands of filters. With oil half warmed up, I could see the oil pressure gauge hit pump relief. Jim found that in his delta-p testing, and only found that the oil had to be pretty cold and thick, along with elevated engine RPM to see filters go into bypass. Of course, these filters that weren't used long, so as the filter loads up the point of bypass becomes more likely. So as mentioned before, warm the oil up pretty good until you smash the gas pedal, and any filter will flow well enough for any stock engine on the road.
 
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