Flow vs filtration rate

Impedance was poor wording on my part and I'm not disputing any of what you guys above are saying or Motorking's data, but those pressure/GPM numbers are based on a specific test sample. There's probably 100 or more different sized filters and so many other variables at play in terms of oil, oil condition and temperatures, it's difficult to say one style media benefits an engine better than another in a full flow filter application. I thought that's what this thread was about, but could have missed the mark.

That test date was on a PureOne PL14006 which is what I'd say is a meduim sized oil filter. It has ~105 sq-in of media (not really alot) and is specifed for large V8 GM vehicles.
 
Impedance was poor wording on my part and I'm not disputing any of what you guys above are saying or Motorking's data, but those pressure/GPM numbers are based on a specific test sample. There's probably 100 or more different sized filters and so many other variables at play in terms of oil, oil condition and temperatures, it's difficult to say one style media benefits an engine better than another in a full flow filter application. I thought that's what this thread was about, but could have missed the mark.

Not quite sure where the disconnect is so let me try to address your comments and let me know if I'm tracking what you are meaning.

The pressure and flow are not coupled in respect to the filter.

The pump is putting out "X" flow (volume) at "Y" RPM ( assuming no suction starvation) regardless of temperature, viscosity, whether its pumping -100w-9000 all purpose weapons grade uni-oil or semi frozen caramel and the filter has nothing to do with that.

The system pressure ( resistance to flow) is based on the size of the passages, length or run relative to flow, tolerances, surface finishes etc. ( which is why when parts wear, pressure decreases and generally pressure increases some with RPM)

"Full flow" is a marketing term and meaningless. Basic fluid dynamics comes into play here. As a filter increases blockage- the areas that are not blocked increase in flow velocity to compensate leaving a net 0 delta in terms of volume flow on either side. ( as measures in front and behind a filter)

The bypass valve is nothing more that a spring loaded cap that when it gets to the stress of the spring it opens allowing bypass- still a net 0 delta in terms of flow volume.

The media ( selection, type and material/construction) has no bearing on either of these- just on how much it can trap until it builds internal pressure where a bypass opens
 
ABN_

I suppose you could call "full flow" a marketing term just like you could a bypass filtration system in the automotive realm. They both filter oil, but usually in a different flow path in the circuit and to a different micron rating.

I get basic fluid dynamics and how filters work. I deal with it every day in industrial applications.

Still not sure what we're agreeing or disagreeing on here, but I'm pretty sure the OP has gotten bored and run off. I know I have at this point. LOL
 
The media design does have an impact on what the "flow vs delta-p" curve (at a specific oil viscosity) will look like. But as mentioned earlier, there will typically only be a few PSI difference between filters in the higher end of flow volume (8~10 GPM) when the oil is hot (~200F). Media bypass valves will not open when the oil is hot unless the filter is very clogged up with debris causing elevated detal-p. High RPM with cold oil is much more likely, and typically does, open the bypass valve for short periods. Keep the engine revs low until the oil warms up.
 
Would an oversized filter run less chance of going into bypass?

The way you phrased the question, no

All things equal and constant, the larger area will buy you time in a given filtration scenario but the chance would not change.
 
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Would an oversized filter run less chance of going into bypass?

Yes slighly, if the media area is somewhat increased, as that will decrease the delat-p at the same flow rate (@ same oil viscosity) and give more holding capacity so the delta-p due to loading won't be as great with the same debris loading.
 
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Something to add … there are not as many fixed rate oil pumps as 10 years ago. As mentioned before … when I apply enough pressure on the throttle (L83) the pressure spike surges right away to supply more volume at the advent of acceleration and stays at the high pressure while the rpm increases
 
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