Hey L.!
We have traveled to the East Coast about 5 times with our, now almost 3 year old daughter, as well as to France.
My advice: don't try to keep him on West Coast Time - it'll just backfire and stress you out. The first day in the new time zone is the hardest, but children actually adjust to time changes faster and easier than adults. I have found going East to take about 24 hours for my daughter to adjust. Coming back home to the West Coast is easy, because we come home in the evening, go to bed and then she wakes up completely adjusted.
The other pp had good advice - be prepared to go with the flow.
Also, bring extra diapers (about 4 more than you think you need), a complete change of clothing for him, and an extra shirt for yourself. My dd once threw up all over me during a flight and I was so glad to have a clean shirt to change into!!
Oh yeah, bring extra plastic baggies - some small, some large. I used one to stuff that smelly shirt into, for example. Another time, I had to change her poopy diaper in an area with no bathrooms (we were on a loooong line in a secured international airport area). Anyway, I was glad to have a plastic bag to stuff that stinky diaper in until I could throw it away.
Have fun!! M.