Yes a bypass filter has smaller pores, (somewhere in the neighborhood of 5 microns (bypass) vs 12 microns (full flow) a micron is a millionth a a meter, about .00004 of an inch you would have to have some awfully tight clearances for a 12 micron chunk to cause any damage) but a full flow filter filters ALL the oil before it gets to the bearing. Whereas a bypass might get 10% of the oil, while the other 90% that is actually going to the bearings have no filtration at all. And true all of the oil might eventually get ran through the filter, but at the same time it is running through the engine picking up contamination that stands a 90% chance of NOT getting filtered out before being used again. This is one of the reasons a car with 100,000 miles on it was nearly unheard of back then. But a bypass filter does pick up a lot of muck and has to help some, and would be period correct if that sort of thing matters to you. Myself I converted my 216 to a full flow filter because that is what I wanted to do.
