Connor Dooley

My great, great grandparents, John Connor and Winifred Dooley emigrated from Ireland around 1833. They were from Birr. Winifred and John spent about a year in New York City before settling in Wheatland near Rochester, NY. 
 

I am searching for any evidence of their roots in Birr and passage to the United States. I have spent many hours searching for information in this regard without success. 

Any ideas or leads would be greatly appreciated.