I just went over the pass from shoreline last week. I went from shoreline (175 st exit) to mt Si trailhead and back with only about 45 minutes of charging in Issaquah at
http://z-home.org/ on the way. Z-homes is the site of the nations first zero net energy development project and there is plenty to see there while you charge up... and the electrons are net solar! If you plan ahead, setting up a tour while you wait is very worth it, the integration of renewable technologies is breathtaking!
Snoqualmie pass takes some patients, you need to drive in the right lane, stay within 2-3 bubbles on the power meter. Of course coming back uses much less power and heavy traffic across the bridge helps too. I was able to do it at around 50 MPH on the steepest part of the climb and about 70 on the way down. By focusing on the power use, the distance you can go is pretty constant, it's the speed that has to vary.
Keep in mind that driving conservatively is the key, to attempt a trip like this I employ hyper miling to some degree. I accelerate and drive within 2-3 bubbles max, use map quest or favored alternative to calculate round trip distance, factor in about 7 miles per bar, zero climate control, hit the trip odometer at the beginning, add the distance traveled to the GOM and keeping the total within the max range needed, favoring bars the first half of the trip and the GOM the second half, shooting for a MPKw average of about 4.5ish.
by using the tools the car came with, you can learn to maximize distance or speed depending on your priorities, and pinpoint VLB to the mile even with fluctuations in elevation.
The longer I own the car the more brilliant I find the range management system and that's saying something considering how impossibly complex and unreliable it seemed at first.
