The best arrangement is a combination of both full-flow and bypass filters. In order to flow enough oil to supply an engine's lubrication needs, a filter must do a mediocre job of trapping contaminants. The "micron" size (the holes the oil flows through) of a full-flow filter is small enough to trap chunks of dirt and metal that could score bearings, but the filter allows a lot of dirt to pass through. A bypass filter can have a much finer pore size, and it can do a much better job of filtering. Since the oil passes through the bypass filter slowly, and returns to the oil pan, it can be filtered very well, and contaminants of a much smaller size can be trapped. However, it would be impossible to flow enough oil through this fine media to lubricate the engine. Full-flow filters get the big chunks; bypass filters actually clean up the oil. Combine the two types of filters with a good-quality detergent oil that suspends the microscopic particles too small for either filter to trap, and you have a very clean-running engine. That's how LuberFiner 750 filters on big rigs have done it for years, one full flow, one bypass, and heavy-duty detergent oil.
Unfortunately, a 235 isn't plumbed for full-flow filtration, and can't be adapted easily. A bypass filter is the only game in town.
Jerry
