I'm currently working on an NTPOG undate for their Honda Prelude filter review.
I've taken apart ALL of the fram filter types available for the H22A4 Honda engine.
The Fram x2 filter is the only heavy duty constructed Fram filter. Unlike the normal Fram filters it does not have ANY cardboard in it. It also filters pretty well (oil analysis shows this).
Unlike the other Fram designs, this filter has 2 layers of media backed by a metal screen (large pores), with metal end caps.
About the only thing I didn't like about it was the standard FRAM by-pass vavle design.
Interestingly, the US OEM filter from Honda is also made by FRAM (though to higher specs) and has the same by-pass design.
I tend to think that the x2 is on the level of the Mobil 1, Bosch, K&N, AMSOIL filters. When I can not get a hold of the Mobil 1 (etc) filters, I use the x2.
I've also taken apart the WIX filters and so on. One guy indicated he's use a Wix filter before a Fram... That's not a bad idea from a construction point of view... but the micron rating on the Wix filters (for the Prelude) are 30 microns. The Mobil 1 is 8-10, the AMSOIL is 8-10, the K&N is 10-20, the x2 is 10-20, the Bosch is 10-12...
-Gerhard
PS Allied Signal merged with Honeywell several years ago. The Honeywell name was more regonizable (from a brand perspective), so Allied kept the name...
[ May 05, 2003, 07:34 AM: Message edited by: Gerhard ]