The FJ60 has an ARB snorkel. Rather than an air scoop it's fitted with a Donaldson cyclonic pre-cleaner. When RPMs and intake air velocity are high enough to spin the incoming air and dirt like a centrifuge and the dirt is slung to the outside of the double walled bowl. When RPMs drop most of the dirt and debris falls to the bottom. I can see bugs and leaves spinning around in there from the drivers seat. Attended Solid Axle Summit - 2 at Ouray. The 60 had some fuel delivery issues so our trail running was limited. We did run Corkscrew Gulch with 5 or 6 other vehicles. We we next to last and there was more dust than I'd ever seen. I'm pretty sure I checked the pre-cleaner bowl before we left and it had little or nothing in it. After we got back some stuff had accumulated in the bowl. It is almost talcum powder fine dust packed tight with some bugs and leaf particles. With a carbureted engine at that altitude seems like keeping the primary air filter as clean as possible is a good idea. Here is what it looks like after SAS-2.