I was told once (a long time ago) that the main difference between automotive and aircraft filters is that the aircraft filters are built for a much higher maximum pressure. Feel the weight - you can tell the metal is thicker. At some pressure any oil filter will distort enough to lift the seal off the surface and blow oil out. The problem occurs on a cold-oil takeoff - max rpm with cold oil. I doubt very much if an automotive oil filter will exceed its pressure rating (which is something around 500 psi), but that's what I was told once upon a time. Another difference is that certified aircraft oil filters have to have a means for positively retaining the filter - a safety wire tab. However, I have never
seen or heard of an oil filter coming loose after having been tightened reasonably. The final difference is that aircraft filters have to have a means of measuring installation torque. But other than that, I suspect automotive filters are at least as good as the aircraft version. You pays your money and takes your choice, I guess.
Gary Casey
Hi Jim -I've meant to answer this for a while, but kept putting it off. I've used a Mobil M1-107 automotive oil filter on my Lycoming IO-320 for over ten years. Them M1-107's gasket fits the standard Lycoming spin-on perfectly. It's a premium automotive filter and, although I don't have emperical evidence, I'm certain it's superior to antiquated 'aviation' oil filter
technology. It's also considerably smaller than the Champion, which might solve your interference problem.Here are Mobil's claims from their website... http://www.mobiloil.com/USA-English/MotorOil/Other_Products/Mobil_1_Extended_Performance_Oil_Filters.aspx1) Remove more contaminants than conventional filters using an advanced synthetic fiber blend filter media2) Holds and remove three times the dirt versus the leading economy filter brand3) Reduces resistance to oil flow while improving filter efficiency4) Withstands up to nine times the normal system operating pressureBill RumburgN403WR (Sonic bOOm)