LS174 is a patent for the filter model released by Purflux, 15 minutes from Paris, in Guyancourt where Renault is.
Most important thing to me in an oil filter is the pressure relief valve.
The springs we see in the pictures have no other role than to hold the cartridge,
The original spring plate found in the Porsche filter could never flatten, the design is so that
the wings of the spring plate touches the filter wall and keeps everything tight inside. LS174 model.
The pressure relief valves of all three filters are inside the elements.
Porsche 993 dual stage oil pump pushes oil @ 9.2 bar to oil filter
Porsche oil pump has dual level pressure relief valves.
In oil filter, pressure relief valve could open a few times, and let unfiltered oil pass.
This could happen when oil is cold and the throttle is pressed,
or when engine running near redline with oil not hot yet.
In 993, a balance of pressure was sought between pump, circuit, pre-filter, post-filter...
Higher pleat automatically means higher flow, more filtering, BUT pressure is inversely proportional
to area. More pleats means more flow but less pressure.
Less pressure to the bearings, I do not want.
More pleats could mean more pressure pre-filter pleats, with cold oil, could open filter relief valve more often.
So logically less pleats is better for thicker oils.

de oliepomp die minder functioneert ook niet want naarmate de olie opwarmt verdwijnt het geluid en dan heeft je pomp geen plotse verjongingskuur ondergaan.