Hacked apart tonight is the Ford FL-300 filter. OEM by Puralator, these are readily available and quite affordable (can be had for under $3). Compared to the Mann W917, they are very slightly wider and about 1/2" longer - not enough to affect usage.

But what's important is the inside ...


- Metal caps on both ends (unlike Fram which uses cardboard).
- An anti-drainback check valve, consisting of a nitrile rubber flap that extends just a little past the inlet holes.
- A strong, spring loaded bypass valve at the inlet end with nitrile rubber seal.
- 54 pleats, each glued down very tightly but unevenly spaced. The paper, which the same synthetic media as used in the Puralator Pure One filters, is thicker than that of the Mann. They are ribbed to keep the pleats separate.
- The filter pleat measured 2-5/8" tall, with 53 of the pleats measuring to 13/16" deep. The pleat at the crimp measured to 7/16".
- Each pleat offers 2 sides, for a total of 108 sides of filter surface.

(2.625*0.8125*106) + (2.625*0.4375*2) = just over 228 sq.in.



By comparison, this was how the Mann W917 fared (same deconstruction as posted here on the Brickboard some months ago ...)


- Metal caps on both ends.
- An anti-drainback check valve, consisting of a nitrile rubber flap that extends well past the holes.
- A spring loaded bypass valve with nitrile rubber seal at the top end, center of the spacer. The spring, though still pretty stong, is not as strong as the one in the Motorcraft.
- 90 pleats, pretty evenly spaced, each glued down very tightly. The paper is ribbed to keep the pleats separate.
- The filter pleat measured 2-1/4" tall, with 89 of the pleats measuring to 25/32" deep. The pleat at the crimp measured to 3/4".
- Each pleat offers 2 sides, for a total of 180 sides of filter surface.

(2.25*0.78125*178) + (2.25*.75*2) yields just over 316 sq.inches.


So what was the purpose? I'm not sure really, except that I wouldn't hesitate on using either of them. The Mann, although having more surface area, has thinner media packed a lot tighter together than the Motorcraft, so it's possible that in total dirt holding ability, both will have similar overall performance. Both have anti-drainback and bypass valves that are effective, and since Ford owns Volvo ... well, won't they both considered OEM nowadays?

So I say it boils down to convenience. Whichever is easier to obtain, go with it and don't worry about it. It's not like they're repainted filters from the makers of the orange can, so.

-- Kane ... of course there's the giant FL-1A, which will win on surface area too. The length does limit its fitment on some Volvo's, however.
--
Blossom II -'91 745Ti/M46 ... Bubbles -'74 144GL/BW35 ... Buttercup -'86 245GL/AW70
The Wayback Machine -'64 P220/M40 ... The ParaBox -'90 745GL/AW70