Admission in PGDIM is done through the percentile scored in CAT. If you are an OBC candidate and looking to get admission to NITIE for PGDIM, then you must have secured an overall percentile of 86.5.
Now, for sectional cut-off for the OBC category, it varies every year. You must score 74 percentile in Quantitative and 74 in Verbal section as well.
These are the latest cut-offs but they depend on the no of total applications and several other factors.