As long as you didn't delete the files or reorganize them you can always download the torrent again and point them to the file.. a check will be performed and it'll start seeding.

I bought myself a seedbox to help out with my ul/dl ratio imbalance on other sites. most ISP have really bad upload rates and if your client isnt configured properly (ports not forwarded) you'll have piss poor connections to others. in one day I took my waffles ratio from .64 to 2.5+ (over 60gb uploaded).. I've been here for a week and my stats are
Seeded: 12.18 GB
Downloaded: 3.57 GB
Reputation: 132
Torrents
Seeding24 Downloading0

I don't think I've downloaded very super popular things either, but a few of the torrents im seeding I have over 20:1 ratio on lol.. I had uploaded over a gig on that particular file before the thing finally finished at 100% (poor seeder) which I guess is why I have such a massive ratio on it.

That aside.. if you can't afford a seedbox you're best to understand your limitation and not go downloading massive amounts like that.. I know this is a public-ish tracker, but on many private ones your account would have been closed/banned already.