Oil filters will have different shells, different media inside, Anti-Drain Back Valve, spring different and oil relieve valve. Maybe even different sealing gaskets. Most times these filters are tested per SAE HS806 (efficiency/capacity). Then and only then can you compare apples to apples. Based soly on looking is not going to get you far. That is like saying oil is bad based on color.
Yes, a bypass will help a lot but factor in the filter replacement price, the by-pass itself and then make-up oil. Unless you put on lot and lots of miles or hours, you will never see a savings. I looked into it and it was cheaper to do oil changes then using a by-pass.
>>>I didn't see any examples to back up this claim, or any evidence. I was able to tell about brands we cut open and wasnt making any scientific claims.
And yes if I pull a dipstick and it looks like rotten fudge, I don't have a problem with calling it bad.
Some people may care more about things than cost, so I offer diverse point of view that may not agree with you. But you didn't pay anything for it.
Theres more to an engines overall lube situation than how long you can leave it in.
We see intakes plugged up all the time from "extended" oil drains that coke up the throttle bores, coat the entire tract with an oily carbony mess from short trips and lack of fuel cleaners and the PCV vapors are responsible. But Im ok if you prefer to do it. The oil may not be worn out, but it will contaminate via PCV.
God bless everyone who runs filthy oil---they pay my mortgage.