What sort of culture shock will I expect as an Iranian emigrating to USA?

Well if you have lived in England for awhile there shouldn't be too many differences. It's mostly the little things. Like you have to tip when you go out for a sit down dinner. We have better food than the Brits. America is huge compared to Europe and things are really spread out so everyone drives everywhere. Unless you are living in Boston, New York City, Chicago etc. Expect the public transportation to be crap. Things are pretty tense between our two countries right now so you may run into some a$$holes (imagine if an American went to live in Iran right now). But for the most part people are pretty friendly. It sounds like your English is pretty good so you should do okay in that department. Overall we are pretty laid back. Women can do whatever they want, wear whatever they want, go wherever they want. I hope this is helpful