i have got a rank of 1625 in jee advanced. i prefer iit delhi, should i go in for chemical engineering(delhi)or production and industrial engineering in delhi or mechanical at kharagpur?

Dude!
I don’t think you should choose your branch in this manner!
Trust me if you do like this, you are gonna regret later!
First decide about the branch in which you are interested (I know you might not be knowing about the various branches, but you should check out the curriculum first and try to google out about the various branches)
Then decide about the college( NOT VICEVERSA)!!
 

Why are you not considering IIT KANPUR.IIIT KANPUR is ranked in many surveys at No.3 after IIT Bombay and IIT Delhi You can go through many opening and closing ranks, you will soon realise the edge of IITK over other IITs. According to your rank, Maths And Computing is a great choice.

Watch out CAMPUS VIDEO IIT KANPUR on youtube .You just see our life once :)

Also go through “thatsiitk” on quora.