I have friends from both IET Lucknow and KNIT Sultanpur and according to them, you will not get any of IET Lucknow or KNIT Sultanpur with this rank. Your OBC rank will not be of any help as selections in the spot round are done based on the general rank and there is no reservation. Also, at IET/KNIT, seats for core branches like CS/EC/ME, fill up first. 

If you are a fresher then I will suggest you take a year drop and appear for various entrance exams next year and, if you are not a fresher then, you can go to other colleges. You will not get the atmosphere like IET Lucknow anywhere else, and hence, taking a year drop will be the best in any case. The environment is very competitive at IET Lucknow. Even KNIT Sultanpur lags in this case. The location of IET Lucknow is perfect for coaching for exams like CAT, GATE, IES, IAS, etc.

Visit the official websites, to get the detailed information regarding the cutoff required at these institutes.