Oil Filter Capacity vs. Flow

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Is it reasonable to assume that a larger area of identical filter media would allow greater flow? I thought that filtration was the most important aspect of a filter, but I'm beginning to think that oil flow may be as important, or even the most important. Any thoughts?
 
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yes it's reasonable to assume that that's why i run an over sized filter on all my cars/truck,more media bigger can means more places for oil to get through to the center tube then back to your engine, vs. maybe your bypass opening up some on a cold winter morn. with a small less media smaller can filter. thats MO and i'm sticking to it!! yes flow is very important...
 
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^^^What he said and I'd rather have plenty of completely unfiltered oil than insufficient flow trying to get every last particle per pass. Filtration efficiency is great, but I suspect that an engine past break-in period, with a good air filter (the most imortant filter by far), and regular oil changes, doesn't have all that much junk in it anyway.
 
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 Originally Posted By: river_rat
^^^What he said and I'd rather have plenty of completely unfiltered oil than insufficient flow trying to get every last particle per pass.
If the by-pass valve is designed correctly and works as designed, then there shouldn't be "insufficient flow". There will be unfiltered flow, but technically not insufficient flow ... that is the sole purpose of the BPV; to ensure the filter element doesn't "choke" the flow too much. Yes, a filter with more media surface area will have less flow restriction than on with less filter surface area, assuming the same media is used in both filters. But, it's also possible that a filter with the smaller filter area will flow better because the media itself is less restrictive. So, bottom line is that it depends on the combination of the media material design and the media surface area.
 
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I want to get all the particles I can, but sure don't want my filter running in bypass mode just driving down the highway.
 
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 Originally Posted By: Audi Junkie
I think flow is overrated, since we have, um, bypass valves.
Flow is not overrated ... it's important and necessary for the engine to remain in good mechanical condition. There's a difference between flow that is filtered vs. flow that is not (ie, flow through the BPV). Ideally, there should never be flow through the BPV unless the filter element is loaded up with a lot of contamination thereby causing excessive flow resistance which could starve the engine.
 
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 Originally Posted By: river_rat
I want to get all the particles I can, but sure don't want my filter running in bypass mode just driving down the highway.
The conditions to make that happen would be extraordinary. I doubt any normal filter with the correct viscosity sees bypass even on a cold start.
 
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Except for loading (which is well into advanced age) there's no reason to ever see elevated PSID unless the pump is in relief. Perhaps briefly at start up when the filter doesn't have a fluid wall behind it. It's a topic that is over obsessed on by most who ponder it.
 
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Most people who run normal and not extended OCI's would not have an issue with filter loading in a normally maintained car. I might worry about flow if I was racing my car alot or had a high flow oil pump. I think most filters flow 7-12 gallons per minute anyway. (That is alot of oil) I would rather have good filtering. **Filters are a combination if quality build, flow, filtering etc.....
 
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 Originally Posted By: Gary Allan
It's a topic that is over obsessed on by most who ponder it.
Over-Obsessed= Typical Bitoger Nonetheless, a true comment. I wonder where the lower limit is, however. Obviously a 1-micron fitlr would be too much for a full flow system, but how fine is practical? I have a 20", 1 micron filter, of a type used for water systems, that I will someday use to filter my waste oil for "recycling" into tractor fuel. Am kinda curious to see how it will come out.
 
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No marketed full flow is too fine by design. Your particular situation/engine condition may require some action. Just compare your experience to the vast majority in your shoes. Do they experience the same thing? If "yes", then there's some merit to your concerns. If "no" then there's still merit to your concerns ..but the problem/perception is limited to you (your engine) and not the filter. I don't think anyone here challenges the holding capacity of their filters.
 

blackdiamond

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 Originally Posted By: Jim Allen
Is this THE JIM ALLEN? I'm a 4x4 guy and have seen you in mags over the years. A navy blue Blazer seems to come to mind, possibly a diesel? I grew up in Colorado in a family that wheeled Blazers. Now I've joined the Toyota world.
 
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 Originally Posted By: Jim Allen
Over-Obsessed= Typical Bitoger
Ya. That's prolly me. I suppose as long as my oil idiot light goes right out on start-up, the filter is good.
 
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 Originally Posted By: Gary Allan
Except for loading (which is well into advanced age) there's no reason to ever see elevated PSID unless the pump is in relief. Perhaps briefly at start up when the filter doesn't have a fluid wall behind it.
The pump doesn't always have to be in relief mode to have a elevated PSID across the oil filter. If the conditions are right enough, the fitter could very well be in bypass mode long after the oil pump is out of relief mode. It all depends on many factors - oil viscosity, pump flow rate vs. engine RPMs, oil pump relief pressure setting, filter by-pass setting, filter media flow resistance characteristics. An extreme example would be a fitter with a by-pass setting of 3 psi and also has a pretty restictive filtering media and/or a small filtering area. Using something like that with a high volume oil pump would probably be in filter by-pass most of the time ... even with HOT oil. Yes, a filter’s design needs to take into account all of these factors, and if not designed properly could very well cause the by-pass valve to open way more than it really should. An old subject of using an 8 psi by-pass filter on a high volume oil pumped Subaru engine that specifies a 23 psi by-pass filter is one example. ;\)
 
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Ah- SuperBusa (I pronounce it SupaBoosah) ..the "hot oil" obsession you have (said like poor lip sync Taiwanese Kung-fu movie - even imagine the facial animations of eyebrows raising and toothy smile) Yes, ..sure...if you're in some obscure miniature corner of the vast galactic universal expanse.
 
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 Originally Posted By: blackdiamond
Is it reasonable to assume that a larger area of identical filter media would allow greater flow? I thought that filtration was the most important aspect of a filter, but I'm beginning to think that oil flow may be as important, or even the most important. Any thoughts?
Probably in the whole picture it won't really make a difference since most engines outlast the rest of the car. The air filter and a good intake seal is by far more important to long engine life.
 
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 Originally Posted By: Gary Allan
Ah- SuperBusa (I pronounce it SupaBoosah) ..the "hot oil" obsession you have (said like poor lip sync Taiwanese Kung-fu movie - even imagine the facial animations of eyebrows raising and toothy smile) Yes, ..sure...if you're in some obscure miniature corner of the vast galactic universal expanse.
Read carefully & open your mind into the the "obscure galactic universe". ;\) I'm not saying it's a common occurrence, but given the right circumstances it CAN happen.
 
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