JEE Advanced maximum marks are not defined :

Maximum Marks vary every year like below:

2017- 366

2016- 372

2015 - 504

2014 - 360

So, it is difficult to predict marks as exam pattern and marks change every year but you should score more than 50% marks to get good branch in Top IITs.

In order to qualify for JEE Advanced you need to score 81 marks in JEE Main in general category according to 2017 cut off.

To check in detail you can also refer to below link

JEE Main Cut Off

Good Luck!!