Ilived in NE Portland when the volcano blew. Emergency and police vehicles
had to improvise by mounting dual stage industrial aircleaners outside the
windows and high up. Lots of duct tape. Standard paper airfilters clogged
quickly and the fine silica ash found it's way into many engines. As Stuart
mentioned the stock VW oilbath filter worked great. The Amsoil oilsoaked foam
air filters seemed to work well also and dealers quickly sold out of them.
Driving through volcanic ash is the worst air filtration test I could
imagine. I can't comment on K&Ns back then but I use them now. I "think" they
are better because of the oil impregnation. Kudos to Bill Davidson for asking
for proof of performance and for "questioning authority", however.

Ken Hunter
82 Westy 1.9D
84 Jetta 1.5D