SSN is one of the top most reputed college in Tamil Nadu and is purely merit based. The cutoff for the college is quite high. A minimum of 195 and above cutoff score is required to get into the college. You should remember that you are competing with the state board students with higher cutoffs. But as engineering is getting less popular nowadys, you can try for the counselling, but still the probability is very low. Do not lose hope, you can try for other good colleges. 

All The Best.