Here are the results with
oil filter temp of 59F and engine speed 3000 rpm 10W40 at an estimated 6gpm.
Motorcraft FL-1HP Before filter 78 psig, after filter 75 psig, car gauge 67 psig
Royal Purple Before filter 77 psig, after filter 75 psig, car gauge 68 psig
Motorcraft FL-1A Before filter 78 pisg, after filter 75 psig, car gauge 68 psig
Bottom line any filter that screws on your engine and does not leak and has a Micron filter under 30 is the best you can get. As you can see there is minimal pressure drop across any filter, in fact 3 psig. The real pressure killer is the POS
oil cooler. I doubt seriously any filter every bypasses so we are filtering 100% of the time.
Again we have been mislead by advertising companies publishing characteritics that add
no value over what you already have.
The number one value filter out there is the Motorcraft FL-1A for $3.79
The number one filter ignoring all cost is the Royal Purple.
Each test took less than 30 seconds and I let the engnine cool for an hour between. Since we do filter 100% of the time and particulate below 25 micron does no damage magnets value is questionable. Since a sbf has than 100 psig
oil pressure any filter has more than adequate burst rating. Since the filters never bypass, any filter is acceptable even dirty side bypass, Since most filters are 25 micron and only get better with contaminants any non-race filter works. There is no wrong answers with your filter choice except Fram. Once I am done with the Royal Purple, I am going with the Ford FL-1A.
Thanks!!!