No problem my friend .

You can not compare fluid filters to air filters micron ratings. I have found this to be very good info about fluid filters micron ratings from the link below.

A couple of years ago I was dealing with a US company that makes a lot of the filter media for fuel filters, to my surprise they said about the same plus a lot of added info for micron ratings. I looked at some of their filter media. the samples of 2 thru 10 true micron media, I could not blow thru it no matter how hard I tried, was so restrictive to my surprise.

Read the link below and what I have always understood was that, very good healthy eyes, 40 microns is the starting point for human visibility. Link below that lists that as well.

http://www.alcofilters.com/getattach...n-Rating.aspx/

A micron is a micron BUP. I'm not comparing air vs oil filtration and the efficiency of said media, I'm sayin there is no way in the world a person with even perfect vision can see a 25 micron particle, be it a airborne particle or one dunked in oil, same thing. The link was to illustrate a specific range of visible particles, airborne or otherwise.

Yes, there seems to be some debate regarding 40-50um being visible with the human eye. The wix racing filter has a nominal rating of around 60-62 from memory. Most of the particles in engine oil are way below this. Guess that's why Blackstone and other analyzers will keep selling particle count services vs hiring the 18 year old kid with 20/20 vision. And in regards to the 25um statement, Im referencing an earlier post.

Is the Napa gold HP1 equivalent any good?.. Compared to Merc that is??

Chris

The advantage of a larger filter is that I get the same flow as a racing filter with twice the filtration. It also has less turbulence at the bottom which allows for more settling especially since I have a large high powered magnet attached to the bottom

Not to hurt anyone's feelings or start an arguement here, but a larger filter absolutely does not equal higher flow. There are small gains, yes, however your larger filter is not anywhere near the 28-30gpm of a wix racing unit. If twice as large equalled twice the flow then why doesn't WIX sell the daylights out of this type of filter in their racing line? The answer is simple, it's the media they choose. 28-30gpm is a ton of flow and most likely overkill for many.

So. Here's my devi's advocate deal again.

If a certain oil filter works well for you, causes no harm with the same motor and environment it's used in, than why research it any further ?

Here's a great quote from Mr Duntov : Why build a swimming pool to prove a bowling ball doesn't float ?

And , again, yes, this info is very good but I would still rather get it from a filter engineer as i do know that filter micron ratings aren't what they appear to be. IE: If a 20 micron filter is 50% effecient at 20 micron, it catches only 50% of the 20 micron particles each pass. And, with paper/ synthetic / fibre filters (being 3d) can filter more fine particles as the material collects contaminants. IE the 'holes' get smaller. The metal screen filters don't as they are 2d. Simple hole pierced in metal sheet. These holes plug to filter, and thus plug as a unit faster and hole size won't change for most of them and thus can't filter finer than the hole size.

National Institute of health disagrees. They say the naked eye can see pollen, which is in the <50 micron range. Many other sources also list particles as small as 25 microns if they are reflective (like, say metal particles). I know for a fact you can see dark partcles on a light background as small as 40 microns, and there is a industry standard test for cosmetics and soaps to do just that. A lab at work does it every day, and there are 40 micron standards the lab techs qualify with.

A good discussion here, with sources, that says 24 microns would be just visible to those with good eyes and 40 microns visible to most.http://www.visionfromfeeling.com/microscopic.html

This surely would be even a better thread if the BORGIE man was around. Where in the world is he. Can we vote to let him back in ?.

As much as I joke about "Where is he"

I hope to God no !!!! He would send PM attacks too,,,,,and then hrs later PM to aplogize.

A true Psycho.

None of us need nor deserve that.