filter flow rates
- Thread starter elric
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The Donaldson P550299 has HUMONGOUS intake holes, a low restriction element, lots of surface area, and in general, just screams, " I AM A HIGH FLOW FILTER!!"
I also have a LF697, and it doesn't appear to have as high flowing baseplate or center tube as the P550299, but I'm just going on appearance.
I also have a LF697, and it doesn't appear to have as high flowing baseplate or center tube as the P550299, but I'm just going on appearance.
It matters not which filter you buy.
The flow rates are virtually the same.
Any new element has a restriction rate of less than 2psi. Generally you are looking at .5 - 1.0 PSID pressure drop on a new element.
The most restrictive element would be one that is "paper" and has a lot of pleats.
You engine won't notice a 1-2 PSID pressure drop. And that's why every engine has some sort of filter by-pass valve in case there is a drop in pressure at a certain rate specified by the engine company.
The flow rates are virtually the same.
Any new element has a restriction rate of less than 2psi. Generally you are looking at .5 - 1.0 PSID pressure drop on a new element.
The most restrictive element would be one that is "paper" and has a lot of pleats.
You engine won't notice a 1-2 PSID pressure drop. And that's why every engine has some sort of filter by-pass valve in case there is a drop in pressure at a certain rate specified by the engine company.
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elric ..basically there is no such thing as a high flow or low flow filter. Typically there is just faster or slower oil moving through it. Naturally conditions and restrictions apply ..and your mileage may vary
I follow you, Gary and FG! (and I went to that thread you linked to and read you post there, Gary.)
So, a Fram Extra Guard's low flow in Grease's test is of no negative consequence in the real world, if I'm reading you correctly, right?
Would a filter with a greater ability to flow be an asset in cold weather, when oil is thicker, so the filter would be in bypass-mode less of the time?
So, a Fram Extra Guard's low flow in Grease's test is of no negative consequence in the real world, if I'm reading you correctly, right?
Would a filter with a greater ability to flow be an asset in cold weather, when oil is thicker, so the filter would be in bypass-mode less of the time?
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Like I said ..conditions and restrictions apply. It all depends on your oil pump relief settings. The pressure is generated from the engine side upstream. That is, the engine takes what it can and creates an escalating pressure increase upstream (most look at this as a pressure drop ..downstream)
Now surely there can be instances where you're going to be in filter bypass ..but my observations say that it's not often for a good life of the filter ..even with thick oil and cold temps.
The part that is rough to get people past is that the engine is an incredible resistance when compared to the oil filter ..and that travelling through the filter is like travelling on a two lane highway and entering 150-300 lane wide toll booth (think of the ^" of the return threaded pipe vs the ^" of media)....
Now ..you may have "conditions and restrictions" that apply in some cases. In these case ..a denser media or anything that could constitute a "restriction" ..may indeed alter flow ..but usually in these situations ..you have an engine that is either old ..or worn ..or both.
Now surely there can be instances where you're going to be in filter bypass ..but my observations say that it's not often for a good life of the filter ..even with thick oil and cold temps.
The part that is rough to get people past is that the engine is an incredible resistance when compared to the oil filter ..and that travelling through the filter is like travelling on a two lane highway and entering 150-300 lane wide toll booth (think of the ^" of the return threaded pipe vs the ^" of media)....
Now ..you may have "conditions and restrictions" that apply in some cases. In these case ..a denser media or anything that could constitute a "restriction" ..may indeed alter flow ..but usually in these situations ..you have an engine that is either old ..or worn ..or both.
Gotcha!
Does Motorcraft fl400s use a paper element with too many pleats?
I got these numbers last year:
Wix 51773 (FL299 version) and 51515 (FL1A version) both flow 7-9 gpm.
Purolator Premium Plus
L40017 flows 7 gpm (FL299 version)
L30001 flows 4 gpm (FL1A version)
L20195 flows 3 gpm (FL400 version)
Fleet Guard LF697 (FL299 version) flows 16 gpm
So I would think the Fleet Guard is going into bypass less often than the Purolator L40017, but if the engine is the main resistance, it may not matter because the difference in bypass time may not be a significant duration.
Wix 51773 (FL299 version) and 51515 (FL1A version) both flow 7-9 gpm.
Purolator Premium Plus
L40017 flows 7 gpm (FL299 version)
L30001 flows 4 gpm (FL1A version)
L20195 flows 3 gpm (FL400 version)
Fleet Guard LF697 (FL299 version) flows 16 gpm
So I would think the Fleet Guard is going into bypass less often than the Purolator L40017, but if the engine is the main resistance, it may not matter because the difference in bypass time may not be a significant duration.
What does the filter going into bypass mode less often mean practically?
At the end of the day the engine gets oil whether through the media or through the bypass, and the only relevant question is the particle count and size after x hours of operation.
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At the end of the day the engine gets oil whether through the media or through the bypass, and the only relevant question is the particle count and size after x hours of operation.
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The less time the oil is bypassing the filter element, the more time it is being filtered.
I understand that.
Let's take two extremes:
Filter A has the same media as the AC-Delco Ultraguard Gold - very fine, but restrictive.
Filter B has the same kind of screen you have on your porch.
Filter B will probably bypass less and spend more time filtering.
I am not sure that after x hours of operation, however, I would not prefer to have used Filter A.
Somewhere between those two extremes there are some questions to answer.
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Let's take two extremes:
Filter A has the same media as the AC-Delco Ultraguard Gold - very fine, but restrictive.
Filter B has the same kind of screen you have on your porch.
Filter B will probably bypass less and spend more time filtering.
I am not sure that after x hours of operation, however, I would not prefer to have used Filter A.
Somewhere between those two extremes there are some questions to answer.
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Yes, but on the same engine ..those numbers don't equate to more flow. (not that you're saying that they are --but) That's what (I think) people integrate it to mean. A 16gpm capable filter is still flowing 3 gpm on a 3gpm engine.
That's why I say, in essense, there is no "high flow" filter. On your car it's the same flow filter....regardless of the filter. The fineness and ^" of the media will vary on how fast it loads and is rendered useless.
So ..we back track to the FL299 and say
.."designed for typical application flows up to 16gpm with 30um nominal yadaya with xx gms of holding capacity ..over a xxxxxx, OEM spec'd, service life.
If you have a 3gpm engine at some speed (flow being somewhat related to rpm), what you should see comparing various filters with different media and media surface areas is a change in the % of time that the filter is in bypass using a new filter.
There is a relationship between the flow rating, the "fineness" of the media, the media surface area, and the actual operation of the filter in a given engine at a given rpm.
That is why, in general, you see higher flow rating filters with higher bypass pressures in many high-performance applications.
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There is a relationship between the flow rating, the "fineness" of the media, the media surface area, and the actual operation of the filter in a given engine at a given rpm.
That is why, in general, you see higher flow rating filters with higher bypass pressures in many high-performance applications.
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