These guys at Paradise Garage are doing some oil longevity testing with an LS1 Camaro. Test is ongoing, and they just finished their Mobil 1 run at 18,000 miles. Amsoil is next up.

I'm very curious to see what they find, but it makes sense that the Amsoil will really excel here, seeing as how it was formulated for this kind of thing.

http://neptune.spacebears.com/cars/stories/oil-life.html

Function before fashion. '96 Contour SE "Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998