I'm planning something similar for 2014. Was going to do it this year but busy renovating a house instead
I've researched a bit. I'm planning to avoid the coastal roads in favour of some of the spectacular mountain passes.
50mph limit everywhere and stonking fines if you get caught
Wild camping is allowed so this would mitigate the rediculous cost of everything in Norway
When I get a chance I'll post some of the roads I was looking at.