You probably won't see any difference in insolubles unless you run the AC Delco to saturation where the M1 may prove to have superior holding capacity. The .2-.4 typical result is too low in resolution to tell you much beyond it being at an acceptable level. If the numbers were 200-400, it would be something that you could see.
Now if you did a particle count, that would show some differences even under the "modeled" method.
That's why I no longer view finer filtration as a feature in anything other than extended drain usage. Well, at least "longer mile" usage. It's more about holding capacity.
Fram sorta has it right (
). It works if you're comparing identical media or identical holding capacity filters (for demonstration purposes)
FRAM Engine Protection ratings are based on multiplying an oil filter's dirt-trapping efficiency by its
dirt-holding capacity
That is, 2 filters that both have (pulling a number out of my behind) 15 grams of holding capacity.
One has a 20um nominal rating, the other a 25um nominal.
Which one will be shot first?
You've also got to keep in mind how the protocol is determined. The multipass rating is determined at saturation. At least that's how I've seen it described (while not actually paying for the SAE ISO document). They put contaminants up stream of the filter until the amount added is seen down stream. At that point, they know the amount of material added (holding capacity) and what made it through on the last evolution before saturation.
You then can figure a lower efficiency media with a lower holding capacity will last just as long.
You turn that around to a higher efficiency media requires more holding capacity to last as long as the lower efficiency media.
What makes it through the lower efficiency media will accumulate. The total accumulation is determined by how long you keep the sump in use.
Running a longer drain sump? Then you may want a higher efficiency media with ample holding capacity ..or you can just accept the higher numbers of smaller particles and use a lower efficiency media with lower holding capacity for the same mileage.
The difference is how you perceive the significance of smaller particles.
PureOne/M1/EaO filters are (most likely) no better than the OCOD for the front end of their lives. The longer the claimed service length, the looser the filter is likely to be when first placed into service. This will be altered to some degree with how advanced the media is, but the fundamental concept remains.
