"GRUMPY,I run 10w30 with some lucas and never seen my oil pressure drop below 25.
I noticed a big difference with oil filters.
I used to use purelator oil filters, now all i use are fram filter..With the previous, purelator brand oil filter I did notice my oil pressure at little low in drive idling at a light around 15."
think it thru ..Hydrodynamics pressure is resistance to flow
so higher viscosity more resistance = higher pressure
if the oil pressure changed and nothing but the filter used was different then the filter with the higher pressure is restricting oil flow, it sure can,t be the bearing clearances, oil pump, etc, those remained constant/un-changed
It could easily be that your dealing with far less total surface area on the fram filter, which could easily be what reduces flow rates, and increases pressure.
it could be that fram filters medium has finer filter medium,that clogs faster, and in theory catches finer size crud, but most filters are designed to capture a fairly standard size range of contaminants
if the filter elements IDENTICAL and the FRAM has 200 inches of filter medium vs lets say 350 for a pureolator filter there should be a reduced restriction to flow of about 57% with the larger surface area with identical filtration, well that is of course with brand mew filters, obviously the smaller filter area will clog much faster as it gets filled with crud in the pores of the filter medium.
but keep in mind the surface area of the filters, and physical construction vary by brand and part number and so does the materials and drain back valve construction.
related info you really should read thru
viewtopic.php?f=54&t=117
viewtopic.php?f=54&t=2187
viewtopic.php?f=54&t=3536
viewtopic.php?f=54&t=3834
I noticed a big difference with oil filters.
I used to use purelator oil filters, now all i use are fram filter..With the previous, purelator brand oil filter I did notice my oil pressure at little low in drive idling at a light around 15."
think it thru ..Hydrodynamics pressure is resistance to flow
so higher viscosity more resistance = higher pressure
if the oil pressure changed and nothing but the filter used was different then the filter with the higher pressure is restricting oil flow, it sure can,t be the bearing clearances, oil pump, etc, those remained constant/un-changed
It could easily be that your dealing with far less total surface area on the fram filter, which could easily be what reduces flow rates, and increases pressure.
it could be that fram filters medium has finer filter medium,that clogs faster, and in theory catches finer size crud, but most filters are designed to capture a fairly standard size range of contaminants
if the filter elements IDENTICAL and the FRAM has 200 inches of filter medium vs lets say 350 for a pureolator filter there should be a reduced restriction to flow of about 57% with the larger surface area with identical filtration, well that is of course with brand mew filters, obviously the smaller filter area will clog much faster as it gets filled with crud in the pores of the filter medium.
but keep in mind the surface area of the filters, and physical construction vary by brand and part number and so does the materials and drain back valve construction.
related info you really should read thru
viewtopic.php?f=54&t=117
viewtopic.php?f=54&t=2187
viewtopic.php?f=54&t=3536
viewtopic.php?f=54&t=3834