Recommendations for fuel filter pre/post fuel pump

[Rembrant]

Guys,

I'm running a little electric fuel pump to supply my 4bbl Summit carb. The pump is linked below:

https://www.holley.com/products/fuel_systems/fuel_pumps_regulators_and_filters/fuel_pumps/carbureted_fuel_pumps/carbureted_electric_fuel_pumps/parts/12-426

I went looking to buy a replacement inlet filter so I had a spare for the one that came with the pump. According to Holley it is an FEP-735, which according to the link below is 74 micron.

https://aftermark.net/fep735-facet-in-line-filter-for-posi-flo-cube-fuel-pumps/

I went to my local CarQuest auto parts store, and they do not have a direct crossover to this FEP735 filter, but they have the exact same filter in 20 micron....not sure of that is correct, because I could almost see through the mesh in it...

It got me thinking...

What micron should* the filters be...for both pump inlet and carburetor inlet?

My carb filter...I thought was 40 micron, but after checking this morning I think it is only 20, according to the auto parts store.

[Gary Lewis]

A 74 micron filter is very coarse.  I looked up the filter for Big Blue, which is a Motorcraft FG872.  I can't find a statement in that listing, but I did find one for another filter that says "Motorcraft Fuel Filters capture 98 percent of particles 8 microns or larger, ensuring a steady flow of clean fuel to your vehicle's engine for top performance."

So I think a 20 micron filter is a lot closer to what you want than a 74.