yeh, id say the tire pressure would be important.
id be more concerned with puncturing the tires on rocks. u know..those little sharp bastards. street tires have a VERY thin carcus. it wont take much to break through.
*on the way down.*
theres a tree right at the end. u have to barely miss the tree on the left, in order to keep your right rear tire on the bridge.
i think its actually a bit worse going up. but yeh, can be tricky with a wide rig.
yeh, that bridge exit/entrance can be a bit tricky. especially with a wider rig. and the section below that is very narrow. i agree, with hitting the main road at that point.
until u get up on manastash ridge, you wont be able to connect with any trails. the naches pass trail you're going to be running from greenwater doesnt intersect with any of those other trails. it ends at pavement.
street legal rigs will be fine. but you wouldnt be able to run quads all the way...
from greenwater to the rocks is gonna be a LONG trip. are u camping once u get there? itd be a VERY long day to run over, check things out, then run back.
if hes having fuel pick up problems, how would FI help?
im in NO way against going FI, i think thats the best choice. but it wont help anything, if the pick-up problem isnt taken care of.