If you want to dowload torrents using evdo, then dont have high expectations.
Firstly all of us have a shared static ip, which means you cannot use private torrent sites.
There is no way to open a port on the Modem given by BSNL, so you can connect to others, but others cannot connect to you, and hence you cannot upload, which will ruin your ratio, so dont even think of private sites.
Even on public trackers, the speeds are usually low unless there are at least 100 seeds.
Because its a wireless connection, speeds will keep fluctuating through out the day.
thanks