The micron rating of the last chance filter would be the same as in the car the injector came from or was used in. Find a filter with that micron rating (the one from the car) and cut it open. Lay out the paper or wire media and measure the square inches. Double that number and buy a filter(s) that have that numberof square inches of media and AN fitting capability.

 

 There is no application for hose barb fittings on an airplane or a race car. Change the filters at annual.

Sintered bronze elements can be plugged solid by a dose of water. I would not use them.  This is race car stuff. My BD-4 hangs from the ceiling unfinished.

Lynn E. Hanover