ZJohnson, the Amsoil Eao fullflow oil filter is the one to get, and the K&N is right behind it. I wish the Amsoil would have the nut welded to the top of the filter like a K&N....ease of R&R is much better.]
Anyway, I have been using the 0-40 Amsoil and the Eao in my Atv engines that hold 2 quarts and have been doing 2,500 mile oil changes which take about 1.5 to 2 years. Right now on the one engine it has 1,500 miles and the oil is clear/brown robust looking oil.
"Success is the ability to go from one failure to another with no loss of enthusiasm."
– Sir Winston Churchill