Mehra said that the changes would appeal to audiences and enable him to "sleep easy".
He told IANS: "The original version did not go down well in India, but was a hit overseas. I realised something was missing, so I went back to the drawing board and changed the script a bit. I re-shot some parts about a month ago.
"I would love to re-release it in cinema halls, but before that we will see how it is received."
Delhi 6, which was released on February 20, stars Abhishek Bachchan and Sonam Kapoor.