If a filter is able to do a really effective job of straining debris out of the oil, it needs to have media with small enough pores that a tiny volume of oil trickles through it. Obviously, a "full flow" filter that passes enough oil to keep the engine lubricated can't do a good job of filtering. The ideal situation would be to have a full flow filter to catch the "rocks, marbles, and bowling balls" like Carter used to describe the woven wire strainers in carburetor inlets, and a bypass filter with a 1-micron media to do the actial filtering. Using a spin-on Diesel fuel filter in a bypass mode in addition to a full flow filter for looks might be a good compromise.
Jerry
