Well guys, the filtrate in the test tubes has to settle out for a day or two, but there is no doubt in my mind that the Bosch is a PureONE clone.
I started with a bubble point test—which if you’ve been following along is the air pressure (in inches of water column) required to break the surface tension of liquid in a saturated media and cause it to fizz out when submerged. This is directly mathematically related to the media’s average pore size. I’m not doing it in such a way that I can figure pore size, so don’t ask—but they can be easily compared from one filter to another; the higher the pressure, the better the filtration.
Submerged in clean WD40:
PureONE and Bosch were tied at 6” water column to begin a steady fizz.
Purolator Classic was about 4” WC—but my regulator sprung a leak so this is approximate.
Just for fun I ran a Denso element and it was just less than 3” WC.
I ran three filtration tests each and by the filtered oil clarity, and the time for the center tubes to fill with oil, that the PureONE and Bosch were indistinguishable from each other. The Purolator Classic filled sooner but the oil was cloudier than these two. It still looked good, but not as clear as the Bosch and PureONE as you would expect. All were cleaner than the Denso which filled very rapidly.
Still, with all these filters dry elements, I could walk around all day and breath though them. None seem restrictive.
I’ll put up pictures when the filtrate settles out.
In the mean time:
Interestingly, all three of these (which are for the same application according to my lookup) have exactly the same amount of media. Same height, depth, and all had 60 pleats.
Bosch:
PureONE:
Purolator Classic:
Plus my dog says hi