Posted by Rara,
"And finally back on topic - The "tests" on the different oil filters are all a bit misleading, because all of the tests are done at different specifications, like the ~14gpm for the K&N and the 3gpm for the motorcraft filter are tested at unknown pressures, if the Motorcraft filter gets 3gpm @ 2psi, and the K&N gets 14gpm at100 psi"
Rara, The K&N oil filter test pressure was 8psi (flow 14 GPM) per their tech rep. The Purlolator (who makes Motorcraft supposedly) tech rep could only tell me that the "Pure One" filter was "tested to manufacturers specs" which I later learned was 3 GPM (psi??) It was NOT TESTED any higher. This is what caused my concern (in view of oil related failures of ?? etio).
Indeed, 3 GPM may be enough for the Duratec (I never found out Duratec oil pump specs but the Yamaha SHO V6 pump is rated to 10 GPM, so ours may be 8-10?). Or Motorcraft may flow 50 GPM but they DID NOT TEST TO MAKE SURE. I doubt it flows as well thogh - recall the oil filter dissection study that discussed the VERY DENSE pleat packing in Pure-one/motorcraft design, they even commented it MAY be a bit flow restrictive. Some of this was discussed at SHOtimes FAQ and they had significant concerns in the about the Motorcraft for this reason. That is what got me thinking. I do not think this matters on 99% of Ford "low reving" applications but on an SVT Duratec spinning 7K RPM with marginal oil capacity??? K&N also has (or so they say) the strongest case in the industry with a 550psi burst strength. Now we also have Demon's oil analysis data showing a better outcome than Motorcraft with same car, same oil, same driver but even more miles. I would say that is a fair pile of evidence in favor of K&N. Until somebody has "better" data favoring something else, I think its worth $10 a pop for the piece of mind. Of course I only drive 10-12K a year and go through about 3 filters so that adds up to an extra $20 year.
As far as the K&N air filter, well it does flow better. 2 persons have dynoed with open K&N and gained 5 HP over stock. I gained 12 HP over stock with an even bigger K&N + 75mm MAF meter. Yes you have to be careful about overoiling to avoid cleaning the MAF sensor frequently. Yes, it was shown in one study to filter slightly less particles than paper, BUT several oil analysis studies have shown that the oil stays just as clean - so this is probably irrelavent. Cost is similar for both perhaps less for reusable K&N in the long run - especially if you change frquently to avoid the big power loss you get with a dirty filter. And FYI, K&N is the factory air filter for the Cobra R, and Viper ACR.
