TallPaul is right! Here's a list of larger filters, including the FL-299. I've cut open "virgin" filters and measured the surface area of the filter element. TP did the same with the Purolator, which I don't have on my list... perhaps he'll post it, as well.
Here's the list:
Code:
Pleat # Element Surface
Depth Pleats Width Area
Motorcraft FL-299 0.750 64 5.50 528.00
Fram PH977A 0.656 56 5.69 418.03
Baldwin BT251 0.750 51 5.38 411.19
Donaldson P550299 0.625 60 5.00 375.00
Wix 51773 0.688 49 5.13 345.30
For Comparison (standard OEM size):
Motorcraft FL-1A 0.719 56 3.75 301.88
The thing to remember is that surface area is
not all there is to the filtering ability of a filter... the element material is at least as important (if not more).