Hello Kiran,
According to last year's cutoffs for Mechanical engineering (which were 761 for PSG, 725 for Anna University), 2018 for MIT(mechanical ss) under OC category), it will be difficult to secure a seat in Mech with your rank. However, it depends on which community you belong to. If you belong to SCA/SC community, you can get Mechanical in these colleges.
To check out last year's cutoffs, visit:
https://images.careers360.mobi/sites/default/files/TNEA-2018-ROUND-1-Opening-Closing-Ranks.pdf
Best Wishes!
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