I am a obc candidate, how many marks I have to get in mains to get a good stream in nit
According, to 2017 cut off you need to score around 220 marks in JEE Main to get top NITs and top branches in OBC category other state quota.
To get admission in NITs you need to score more then 125 marks.
To score good marks in JEE Main work on your concepts you can take help of NCERT books. Focus on the topics which carries more weightage in the exam. Refer previous year papers and mock test series for your practice.
All the Best!!