The only way to do so is to have more seeders and peers (people with partial files who are trying to download the rest). Also each seeder / peer can limit the upload data rate. Therefore, if I set an upload limit of 50kb, then the max rate is 50kb no matter how many people are connected. 50 people connected? They each get 1kb.
It seems you are fighting with other peers trying to download the files from the limited number of seeders.