Ok so why isn't 99.9% more restrctive

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Just wondering how oili filters can catch all but everything yet still not restrict the flow of the oil. Does this put any additional pressure on the oil pump that wasn't intended by the engineers of the vehicle?
 
It will be more restrictive. It has to be on a per unit area basis. The cell structure must be tighter in order to grab more dirt first pass.

Realize that media DOES NOT do the filtration, the cake does long-term.

You can solve pressure issues with more surface area, which is why the area inside is important too.
 
Originally Posted By: JHZR2
You can solve pressure issues with more surface area, which is why the area inside is important too.


Or use OEM filters?
 
Originally Posted By: AnarchyX
Just wondering how oili filters can catch all but everything yet still not restrict the flow of the oil. Does this put any additional pressure on the oil pump that wasn't intended by the engineers of the vehicle?


Using the right amount of surface area is part of the design of a highly efficient oil filter.

If "Filter A" is a little more restrictive than "Filter B", then the oil pump will have to work a little more to pump the same flow rate of oil through Filter A. This will only be a few PSI more in most cases, and the oil pump's pressure relief/bypass setting is usually set high enough to take up any differences in filter restrictiveness. The engine would not see any flow restriction unless the oil pump was in pressure relief/bypass mode and Filter A was much more restrictive than Filter B.
 
Originally Posted By: Kaie
Or use OEM filters?


Bingo! That's one of several reasons I prefer Motorcraft filters for my 3.0 Fusion. The recent (late 2008) spec change from the FL-820S to the FL-500S was supposedly related to an oil pump/flow rate change.

I have confidence in the Ford/Motorcraft/filter specs transition when such changes occur.
 
No one really knows what the flow vs. psid curve is for any filter unless you do the test and generate it. But, one would think/hope that the OEM filters have been tested to determine this.

On the same train of thought ... you would expect the aftermarket filter makers to also do flow vs. psid testing to ensure they are not making a filter that is going to ruin an engine.

Here's an example of real test data:
http://www.bobistheoilguy.com/forums/ubb...451#Post1619451

As you can see ... even a very efficient filter can flow well if it's designed correctly.
 
That's a good question. They can layer the media, combine different media materials in one layer, adjust the area of the media with more/less pleats, and probably other things I as a layman don't know.

The oil pump pressure is determined by the pump output and the most restrictive system outlet opening, which I believe is usually the main/rod bearings.
 
Originally Posted By: goodtimes

The oil pump pressure is determined by the pump output and the most restrictive system outlet opening, which I believe is usually the main/rod bearings.


Yep .. good rule of thumb is that the oil filter is responsible for only 1/15th the total pressure drop in the system. In other words, the engine's oiling system is 15 times more restrictive than the oil filter.
 
Originally Posted By: daman
That's why i always use over sized/bigger filters for more surface area.


You're running the risk of wrong oil pressure. If that matters to you. In theory i guess. i have no proof of this.
 
The reason a higher efficincy synthetic media or blend can be as free flowing or more than a cellulose filter is because of more uniform pore size.
 
Originally Posted By: Kaie
Originally Posted By: daman
That's why i always use over sized/bigger filters for more surface area.


You're running the risk of wrong oil pressure. If that matters to you. In theory i guess. i have no proof of this.

How you figure? pump pumps the same once the filter is full.
 
AnarchyX, oil filters DON'T catch ALL. There is much marketing/advertising when making oil filter claims.

Hallmark, an automaker changes the filter because of some cost cutting in the engine? Looks like the FL500s is smaller and has a lower bypass pressure. If you need more oil flow, spend the $1 extra on a bigger oil pump. Reducing loss through the filter sounds like a reason for me to stop shopping at the Ford dealership. Asked Ford why the FL2005 is available anymore? Why the FL400s wasn't good enough and now is? I wager more likely to assembly line ease and cost cutting and nothing else brought about the FL500. And, if it was better, why wasn't the 500 backspec'd for the 820s?

Kaie, oil pressure is overly variable with oil temp. I wouldn't worry about a couple PSI with a filter change unless you're on the ragged edge of 'under engineering'. Makes you wonder?

Daman, pumps have "blow by" just like your engine. So, pumps NEVER pump the same. Pump temperature, oil temperature, and flow resistance will vary the output of a pump.
 
Originally Posted By: ZeeOSix
Here's an example of real test data:
http://www.bobistheoilguy.com/forums/ubb...451#Post1619451

As you can see ... even a very efficient filter can flow well if it's designed correctly.
Yes, that is the email from Purolator engineering to a member, SuperBusa, answering his question regarding the 99.9% Pure One flow vs PSID for use in a Corvette. It shows the P1 to be a very free flowing filter. Later in the thread, the results are put in a graph. Excellent information/thread.

Originally Posted By: ZeeOSix
Originally Posted By: goodtimes

The oil pump pressure is determined by the pump output and the most restrictive system outlet opening, which I believe is usually the main/rod bearings.

Yep .. good rule of thumb is that the oil filter is responsible for only 1/15th the total pressure drop in the system. In other words, the engine's oiling system is 15 times more restrictive than the oil filter.

So, the oiling system itself is more restrictive when compared to the filter. Good information. I have no concern about using P1 or the Bosch DP I just acquired in an AAP oil/filter promo.
 
Originally Posted By: unDummy
Daman, pumps have "blow by" just like your engine. So, pumps NEVER pump the same. Pump temperature, oil temperature, and flow resistance will vary the output of a pump.

Yes i know that,,i'm talking "A"/one pump,not all pumps in general,,,it'll flow about the same no matter what filter is on,been there done that with testing of various filters for crossing purposes.

never have i had a issue either in flow OR PSI changing filters brands or going up in size.
 
If more people put an oil pressure gauge, after the filter, that would probably kill this whole re-occuring restrictive filter thing.

I got pressure gauges on four cars I've had so far, and still no discernable oil pressure difference in any of them, down stream with filter changes from OEM's...Wix's to PureOne, Fram, STP etc, shorties or longies of all the many ones I've tried.

Oh sure-there may be a psi or two, but not enough that I can tell on a gauge.

I don't think its an issue. Never seen it anyway.
Does anyone actually know anyone who has ever had oil pressure issues in a non-defective and correct size filter?
 
Originally Posted By: river_rat
If more people put an oil pressure gauge, after the filter, that would probably kill this whole re-occuring restrictive filter thing.


I wonder how many are located before the filter? If someone installs an aftermarked oil pressure gauge, it's possible most of them get tapped in before the filter. I know on every vehicle I own the factory sensor it located after the filter.

Originally Posted By: river_rat
I got pressure gauges on four cars I've had so far, and still no discernable oil pressure difference in any of them, down stream with filter changes from OEM's...Wix's to PureOne, Fram, STP etc, shorties or longies of all the many ones I've tried.


Same here. I've used 4 or 5 different brand filters on one car (has digital oil press & temp readout) and the oil pressure is the same at the same oil temp and engine RPM between them all. I'm sure if I did a oil pressure test at redline with cold oil (with pump in pressure relief mode) I might see a few PSI difference between them.
 
Originally Posted By: ZeeOSix
I wonder how many are located before the filter?

I've not seen one.
Easy to find out. I put a new rubber adapter hose (that fits a garbage disposal drain) from a hardware store and adapted that to my air compressor with a few pieces of hose and clamps. All clean of course so no dirt gets into the engine.
That way I could put about 30 psi air into the oil filter nipple--with the filter removed, obviously.
Turned on the ignition without cranking the engine and see if the oil pressure light goes out.
Assuming it does go out, then I can tee into the oil pressure sending unit hole for the sensor and the new gauge.

There are also screw-on filter plate adapters that sandwich between the filter and it's mount to adapt for a gauge.

(Also, just for fun, I blew with my mouth through that hose with the compressor disconnected, and felt how much resistance there is in the oil galleries and bearings where the oil must go, and compared that to getting air through an empty but oiled filter media and the filter was a pretty low resistance by comparison. The ADBV was actually more restrictive than the media.)
 
You could probably also just blow into the nipple and feel for air coming out the OP sender hole. I like to overcomplicate things.
 
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