The idea to make SHOR came to Manoj Kumar while he was relaxing at his farmhouse in Delhi, after completing PURAB AUR PASCHIM. A few friends commented on how peaceful it was and that there was no ' shor' in the vicinity.
Manoj Kumar approached Shatrughan Sinha for the film. But Shatrughan could not give bulk dates. That is when Prem Nath was signed.
A dejected Amitabh used to be a regular visitor on the sets of Shor. He was dating Jaya at the time and did not have much work. Manoj Kumar befriended him, saw a certain spark and knew he had potential. He signed him up for a supporting role in his next film Roti Kapda Makaan. Amitabh had risen to be a top hero by the time Roti Kapda aur Makaan released
Manoj Kumar attempted to sign Pran for the role of the pathan. But Pran was already signed for Zanjeer. He did not want to play the role of a pathan in 2 films. Eventually Prem Nath was signed.
Jaya Bachchan clashed with Manoj Kumar while the film was being made. She called him a bully and said his "bharat" image was all a show. She mentioned his attitude was very arrogant and was upset he did not call her for any trial showings. Manoj stated after he saw Guddi, he wrote Shor with Jaya in mind. He did not invite Jaya for the trial showings because the trail showings were held with the purpose of editing the film. The film was not completed at that point .