Last rank(General rank) admitted under ETB reservation in CS in SOE under free seat was 3696 and EC was 4205,your rank is 2917,so you have strong chances to get a free seat in both these branches even if there is rush.Overall you have strong chances of getting a free seat in all the branches in SOE except naval architecture & ship building. ALL THE BEST :) CHECK LAST RANK ADMITTED UNDER ETB RESERVATION HERE-:
http://cxpr.in/1nCZaFm Note:-Given ranks are GENERAL rank not CATEGORY rank.